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1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
2<html><head>
3<meta content="text/html; charset=ISO-8859-1" http-equiv="content-type"><title>PALM chapter 4.2</title></head>
4<body><h3 style="line-height: 100%;"><a name="Kapitel4.2"></a>4.2 <a href="#Laufparameter">Runtime
5parameters</a> and <a href="#Paketparameter">package
6parameters</a></h3>
7<h3 style="margin-bottom: 0cm; line-height: 100%;"><a name="Laufparameter"></a>Runtime parameters:</h3>
8<br><br><table style="text-align: left; width: 100%;" border="1" cellpadding="2" cellspacing="2"> <tbody>
9<tr>
10<td style="vertical-align: top;"><font size="4"><b>Parameter
11name</b></font></td> <td style="vertical-align: top;"><font size="4"><b>Type</b></font></td>
12<td style="vertical-align: top;"> <p><b><font size="4">Default</font></b> <br> <b><font size="4">value</font></b></p> </td>
13<td style="vertical-align: top;"><font size="4"><b>Explanation</b></font></td>
14</tr> <tr> <td style="vertical-align: top;"><a name="averaging_interval"></a><span style="font-weight: bold;">averaging_interval</span><br>
15</td> <td style="vertical-align: top;">R<br> </td>
16<td style="vertical-align: top;"><span style="font-style: italic;">0.0</span><br> </td>
17<td style="vertical-align: top;">Averaging interval for
18all&nbsp;output of temporally averaged data (in s).<br><br>This
19parameter defines the time interval length for temporally averaged data
20(vertical profiles, spectra, 2d cross-sections, 3d volume data). By
21default,&nbsp;data are not subject to temporal averaging. The
22interval
23length is limited by the parameter <a href="#dt_data_output_av">dt_data_output_av</a>.
24In any case, <span style="font-weight: bold;">averaging_interval</span>
25&lt;= <span style="font-weight: bold;">dt_data_output_av</span>
26must hold.<br><br>If
27an interval is defined, then by default the average is calculated from
28the data values of all timesteps lying within this interval. The number
29of time levels entering into the average can be reduced with the
30parameter <a href="#dt_averaging_input">dt_averaging_input</a>.<br><br>If
31an averaging interval can not be completed at the end of a run, it
32will be finished at the beginning of the next restart run. Thus for
33restart runs, averaging intervals do not
34necessarily begin at the beginning of the run.<br><br>Parameters
35<a href="#averaging_interval_pr">averaging_interval_pr</a>
36and <a href="#averaging_interval_sp">averaging_interval_sp</a>
37can be used to define different averaging intervals for vertical
38profile data and spectra, respectively.<br> </td> </tr>
39<tr> <td style="vertical-align: top;"> <p><a name="averaging_interval_pr"></a><b>averaging_interval_pr</b></p>
40</td> <td style="vertical-align: top;">R<br> </td>
41<td style="vertical-align: top;"><span style="font-style: italic;">value of <a href="#averaging_interval">averaging_<br>
42interval</a><br>
43</span> </td> <td style="vertical-align: top;"><p>Averaging
44interval for output of vertical profiles&nbsp;to
45local
46file <font color="#000000"><font color="#000000"><a href="chapter_3.4.html#DATA_1D_PR_NETCDF">DATA_1D_PR_NETCDF</a>
47</font></font>and/or&nbsp; <a href="chapter_3.4.html#PLOT1D_DATA">PLOT1D_DATA</a>
48(in s).&nbsp; </p> <p>If
49this parameter is given a non-zero value, temporally
50averaged vertical profile data are output. By default, profile data
51data are not subject to temporal averaging. The interval length is
52limited by the parameter <a href="#dt_dopr">dt_dopr</a>.
53In any case <b>averaging_interval_pr</b> &lt;= <b>dt_dopr
54</b>must
55hold.</p>If an interval is defined, then by default the average
56is calculated
57from the data values of all timesteps lying within this interval. The
58number of time levels entering into the average can be reduced with the
59parameter <a href="#dt_averaging_input_pr">dt_averaging_input_pr</a>.
60<p>If
61an averaging interval can not be completed at the end of a run, it will
62be finished at the beginning of the next restart run. Thus for restart
63runs, averaging intervals do not
64necessarily begin at the beginning of the run.</p> </td> </tr>
65<tr> <td style="vertical-align: top;"><a name="call_psolver_at_all_substeps"></a><span style="font-weight: bold;">call_psolver_at_all_<br>
66substeps</span></td> <td style="vertical-align: top;">L<br>
67</td> <td style="vertical-align: top;"><span style="font-style: italic;">.T.</span><br> </td>
68<td style="vertical-align: top;">Switch
69to steer the call of the pressure solver.<br> <br>
70In order to speed-up performance, the Poisson equation for perturbation
71pressure (see <a href="#psolver">psolver</a>) can
72be called only at the last substep of multistep Runge-Kutta
73timestep schemes (see <a href="chapter_4.1.html#timestep_scheme">timestep_scheme</a>)
74by setting <span style="font-weight: bold;">call_psolver_at_all_substeps</span>
75= <span style="font-style: italic;">.F.</span>.
76In many cases, this sufficiently reduces the divergence of the velocity
77field. Nevertheless, small-scale ripples (2-delta-x) may occur. In this
78case and in case
79of non-cyclic lateral boundary conditions, <span style="font-weight: bold;">call_psolver_at_all_timesteps</span>
80= <span style="font-style: italic;">.T.</span>
81should be used.&nbsp;<span style="font-weight: bold;"></span></td>
82</tr> <tr> <td style="vertical-align: top;"><p><a name="fcl_factor"></a><b>cfl_factor</b></p>
83</td> <td style="vertical-align: top;">R<br> </td>
84<td style="vertical-align: top;"> <p><i>0.1,
850.8 or 0.9</i> <br> <i>(see right)</i></p>
86</td> <td style="vertical-align: top;"> <p lang="en-GB">Time step limiting factor.&nbsp; </p>
87<p><span lang="en-GB">In the model, the <span lang="en-GB">maximum
88allowed </span>time step according to CFL and
89diffusion-criterion
90dt_max is reduced by </span><a href="chapter_4.1.html#dt"><span lang="en-GB">dt</span></a> <span lang="en-GB">=
91dt_max * <b>cfl_factor</b>
92in order to avoid stability problems which may arise in the vicinity of
93the maximum allowed timestep. The condition <i>0.0</i>
94&lt; <b>cfl_factor</b>
95&lt; <i>1.0 </i>applies.<br> </span></p>
96<p><span lang="en-GB">The default value of
97cfl_factor depends on
98the </span><a href="chapter_4.1.html#timestep_scheme"><span lang="en-GB">timestep_scheme</span></a><span lang="en-GB"> used:<br> </span></p> <p><span lang="en-GB">For the third order Runge-Kutta scheme it
99is <b>cfl_factor</b> = </span><span style="font-style: italic;">0.9</span><span lang="en-GB">.<br> </span></p> <p><span lang="en-GB">In case of the leapfrog scheme a quite
100restrictive value of <span style="font-weight: bold;">cfl_factor</span>
101= <span style="font-style: italic;">0.1 </span></span><span lang="en-GB">is used because for larger values the velocity
102divergence
103significantly effects the accuracy of the model results.</span><a href="chapter_4.1.html#scalar_advec"><span lang="en-GB"></span></a><span lang="en-GB"> Possibly larger values may
104be used with the leapfrog scheme but these are to be determined by
105appropriate test runs.<span style="font-family: times new roman;"><br>
106</span></span></p> <span lang="en-GB"><span style="font-family: times new roman;"></span><font face="Times New Roman">The default value for the Euler
107scheme is <span style="font-weight: bold;">cfl_factor</span>
108= <span style="font-style: italic;">0.8</span> .</font></span></td>
109</tr><tr> <td style="vertical-align: top;"> <p><a name="create_disturbances"></a><b>create_disturbances</b></p>
110</td> <td style="vertical-align: top;">L<br> </td>
111<td style="vertical-align: top;"><span style="font-style: italic;">.T.</span><br> </td>
112<td style="vertical-align: top;"> <p>Switch to
113impose random perturbations to the horizontal
114velocity field.&nbsp; </p> <p>With <b>create_disturbances</b>
115= <i>.T.,</i> random
116perturbations can be imposed to the horizontal velocity field at
117certain times e.g. in order to trigger off the onset of convection,
118etc..<br> </p> <p>The temporal interval between
119these times can be steered with <a href="#dt_disturb">dt_disturb</a>,
120the vertical range of the perturbations with <a href="#disturbance_level_b">disturbance_level_b</a>
121and <a href="#disturbance_level_t">disturbance_level_t</a>,
122and the perturbation amplitude with <a href="#disturbance_amplitude">disturbance_amplitude</a>.
123In case of non-cyclic lateral boundary conditions (see <a href="chapter_4.1.html#bc_lr">bc_lr</a>
124and <a href="chapter_4.1.html#bc_ns">bc_ns</a>),
125the horizontal range of the perturbations is determined by <a href="chapter_4.1.html#inflow_disturbance_begin">inflow_disturbance_begin</a>
126and <a href="chapter_4.1.html#inflow_disturbance_end">inflow_disturbance_end</a>.
127A perturbation is added to each grid point with its individual value
128determined by multiplying the disturbance amplitude with a uniformly
129distributed random number.
130After this, the arrays of u and v are smoothed by applying a
131Shuman-filter twice and made divergence-free by applying the pressure
132solver.<br> </p> <p>The random number generator to
133be used can be chosen with <a href="chapter_4.1.html#random_generator">random_generator</a>.<br>
134</p> <p>As soon as the desired flow features have
135developed
136(e.g.&nbsp; convection has started), further imposing of
137perturbations
138is not necessary and can be omitted (this does not hold for non-cyclic
139lateral boundaries!). This can be steered by assigning
140an upper limit value for the perturbation energy (the perturbation
141energy is defined by the deviation of the velocity from the mean flow)
142using the parameter <a href="#disturbance_energy_limit">disturbance_energy_limit</a>.
143As soon as the perturbation energy has exceeded this energy limit, no
144more random perturbations are assigned<br>
145.&nbsp; <br>
146Timesteps where a random perturbation has been imposed are marked in
147the local file <a href="chapter_3.4.html#RUN_CONTROL">RUN_CONTROL</a>
148by the character "D" appended to the values of the maximum horizontal
149velocities. </p> </td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="cross_normalized_x"></a><b>cross_normalized_x</b></p>
150</td> <td style="vertical-align: top;">C*10&nbsp;
151<br>&nbsp;&nbsp; (100)</td> <td style="vertical-align: top;"><i>100 * ' '</i></td>
152<td style="vertical-align: top;"> <p>Type of
153normalization applied to the x-coordinate of vertical
154profiles to be plotted with <span style="font-weight: bold;">profil</span>.</p>
155<p>This parameter only applies for &nbsp;<a href="chapter_4.2.html#data_output_format">data_output_format</a>
156= <span style="font-style: italic;">'profil'</span>.</p><p>If
157vertical profiles are plotted with the plot software <span style="font-weight: bold;">profil</span> (data on
158local file <a href="chapter_3.4.html#PLOT1D_DATA">PLOT1D_DATA</a>,
159parameters on local file <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/PLOT1D_PAR">PLOT1D_PAR</a>)
160the x-values of the data points can be normalized with respect to
161certain quantities (e.g. the near-surface heat flux) in order to ensure
162a better comparability. This type of normalization then applies to all
163profiles of one coordinate system (panel). The normalization quantities
164are re-calculated for each output time of each individual profile. If
165temporally averaged profiles are output (see <a href="#averaging_interval_pr">averaging_interval_pr</a>),
166then the normalization quantities are also temporally averaged
167accordingly. If the value of a normalization quantity becomes zero,
168then normalization for the total respective coordinate system (panel)
169is switched off automatically (also for the y-axis).<br> </p>
170<p>By default, the normalization quantities are calculated as the
171horizontal mean of the total model domain and and these values are also
172used for the normalization of profiles from subdomains (see <a href="chapter_4.1.html#statistic_regions">statistic_regions</a>).
173Instead of this, they can be calculated from the data of a certain
174subdomain by using the parameter <a href="#normalizing_region">normalizing_region</a>
175(however, they are used again for all subdomains and even for the total
176domain).&nbsp; </p> <p>The user can choose between
177the following normalization
178quantities: <br> </p> <table style="text-align: left; width: 100%;" cellpadding="2" cellspacing="2"> <tbody> <tr> <td style="vertical-align: top;"><i>'wpt0'</i></td>
179<td style="vertical-align: top;">Normalization with
180respect
181to the total surface sensible heat
182flux (k=0 ).</td> </tr> <tr> <td style="vertical-align: middle;"><i>'ws2'</i></td>
183<td style="vertical-align: top;">Normalization with
184respect
185to w<sub>*</sub> <sup>2</sup>
186(square of the characteristic vertical wind speed of the CBL)</td>
187</tr> <tr> <td style="vertical-align: top;"><i>'tsw2'</i></td>
188<td style="vertical-align: top;">Normalization with
189respect
190to the square of the characteristic
191temperature of the CBL theta<sub>*</sub> (this is defined
192as ratio of
193the surface heat flux and w<sub>*</sub>).</td> </tr>
194<tr> <td style="vertical-align: middle;"><i>'ws3'</i></td>
195<td style="vertical-align: top;">Normalization with
196respect
197to w<sub>*</sub> <sup>3</sup>.</td> </tr>
198<tr> <td style="vertical-align: middle;"><i>'ws2tsw'</i></td>
199<td style="vertical-align: top;">Normalization with
200respect
201to w<sub>*</sub><sup>2</sup>theta<sub>*</sub>
202(for definition of theta<sub>*</sub> see <span style="font-style: italic;">'tsw2'</span>).</td>
203</tr> <tr> <td style="vertical-align: middle;"><i>'wstsw2'</i></td>
204<td style="vertical-align: top;">Normalization with
205respect
206to w<sub>*</sub><sup>2 </sup>theta<sub>*</sub>
207(for definition of theta<sub>*</sub> see <span style="font-style: italic;">'tsw2'</span>).</td>
208</tr> </tbody> </table> <p>For each
209coordinate system (panel) to be drawn (see <a href="#cross_profiles">cross_profiles</a>)
210an individual normalization quantity can be assigned. For example: if <span style="font-weight: bold;">cross_normalized_x</span> =
211<span style="font-style: italic;">'ws2'</span><i>,'ws3'</i>,
212then the
213x-values in the 1st coordinate system are normalized with respect to w<sub>*</sub><sup>2</sup>
214and in the 2nd system with respect to w<sub>*</sub><sup>3</sup>.
215Data
216of the further coordinate systems (if any are to be drawn) are not
217normalized.&nbsp; </p> <p>Using a normalization
218leaves all vertical profile data on
219local file <a href="chapter_3.4.html#PLOT1D_DATA">PLOT1D_DATA</a>
220unaffected, it only affects the visualization. Within <span style="font-weight: bold;">profil</span>, the
221normalization is steered
222by parameter <a href="http://www.muk.uni-hannover.de/institut/software/profil_beschreibung.html#NORMX">normx</a>
223which may be changed subsequently by the user in the parameter file
224(local file <a href="chapter_3.4.html#PLOT1D_PAR">PLOT1D_PAR</a>).<br>
225&nbsp;<br>
226The assigned normalization quantity is noted in the axes labels of the
227respective coordinate systems (see <a href="#cross_xtext">cross_xtext</a>).</p>
228</td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="cross_normalized_y"></a><b>cross_normalized_y</b></p>
229</td> <td style="vertical-align: top;">C*10&nbsp;
230<br>&nbsp;&nbsp; (100)</td> <td style="vertical-align: top;"><i>100 * ' '</i></td>
231<td style="vertical-align: top;"> <p>Type of
232normalization applied to the y-coordinate of vertical
233profiles to be plotted with <span style="font-weight: bold;">profil</span>.&nbsp;</p>
234<p>This parameter only applies for &nbsp;<a href="chapter_4.2.html#data_output_format">data_output_format</a>
235= <span style="font-style: italic;">'profil'</span>.</p><p>If
236vertical profiles are plotted with the plot software <span style="font-weight: bold;">profil</span> (data on
237local file <a href="chapter_3.4.html#PLOT1D_DATA">PLOT1D_DATA</a>,
238parameter on local file <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/PLOT1D_PAR">PLOT1D_PAR</a>)
239the y-values of the data points can be normalized with respect to
240certain quantities (at present only the normalization with respect to
241the boundary layer height is possible) in order to ensure a better
242comparability. </p> <p>The user can choose between the
243following normalization
244quantities: <br> </p> <table style="text-align: left; width: 100%;" cellpadding="2" cellspacing="2"> <tbody> <tr> <td style="vertical-align: top;"><i>'z_i'</i></td>
245<td style="vertical-align: top;">Normalization with
246respect
247to the boundary layer height
248(determined from the height where the heat flux achieves its minimum
249value).</td> </tr> </tbody> </table> <p>For
250further explanations see <a href="#cross_normalized_x">cross_normalized_x.</a></p>
251</td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="cross_profiles"></a><b>cross_profiles</b></p>
252</td> <td style="vertical-align: top;">C*100&nbsp;
253<br>&nbsp;&nbsp; (100)</td> <td style="vertical-align: top;">see right<br> </td>
254<td style="vertical-align: top;"> <p>Determines
255which vertical profiles are to be presented in
256which coordinate system if the plot software <span style="font-weight: bold;">profil</span> is used.
257&nbsp; </p> <p>This parameter only applies for
258&nbsp;<a href="chapter_4.2.html#data_output_format">data_output_format</a>
259= <span style="font-style: italic;">'profil'</span>.</p><p>The
260default assignment is:&nbsp; </p> <p><b>cross_profiles</b>
261=&nbsp; </p> <ul> <p><span style="font-family: monospace; font-style: italic;">'
262u v ',</span><br> <span style="font-family: monospace; font-style: italic;">' pt
263',&nbsp; </span><br style="font-family: monospace; font-style: italic;"> <span style="font-family: monospace; font-style: italic;">'
264w"pt" w*pt* w*pt*BC wpt wptBC ',&nbsp; </span><br style="font-family: monospace; font-style: italic;"> <span style="font-family: monospace; font-style: italic;">'
265w"u" w*u* wu w"v"w*v* wv ',&nbsp; </span><br style="font-family: monospace; font-style: italic;"> <span style="font-family: monospace; font-style: italic;">' km
266kh ',</span><br style="font-family: monospace; font-style: italic;"> <span style="font-family: monospace; font-style: italic;">' l '
267,</span><br>
26814 * <span style="font-family: monospace; font-style: italic;">'
269'</span></p> </ul> <p>If plot output of
270vertical profiles is produced (see <a href="#data_output_pr">data_output_pr</a>),
271the appropriate data are written to the local file <a href="chapter_3.4.html#PLOT1D_DATA">PLOT1D_DATA</a>.
272Simultaneously, the model produces a parameter file (local name <a href="chapter_3.4.html#PLOT1D_PAR">PLOT1D_PAR</a>)
273which describes the layout for a plot to be generated with the plot
274program <span style="font-weight: bold;">profil</span>.
275The parameter <b>cross_profiles</b>
276determines how many coordinate systems (panels) the plot contains and
277which profiles are supposed to be drawn into which panel. <b>cross_profiles</b>
278expects a character string (up to 100 characters long) for each
279coordinate system, which consists of the names of the profiles to be
280drawn into this system (all available profiles and their respective
281names are described at parameter <a href="#data_output_pr">data_output_pr</a>).
282The single names have to be separated by one blank (' ') and a blank
283must be spent also at the beginning and at the end of the
284string.&nbsp; </p> <p>Example:&nbsp; </p> <ul>
285<p><b>cross_profiles</b> = <span style="font-family: monospace; font-style: italic;">' u v ',
286' pt '</span></p> </ul> <p>In this case the
287plot consists of two coordinate systems
288(panels) with the first panel containing the profiles of the horizontal
289velocity components (<span style="font-style: italic;">'u'</span>
290and <span style="font-style: italic;">'v'</span>)
291of all output times (see <a href="#dt_dopr">dt_dopr</a>)
292and the second one containing the profiles of the potential temperature
293(<span style="font-style: italic;">'pt'</span>).<br>
294</p> <p>Whether the coordinate systems are actually drawn,
295depends on
296whether data of the appropriate profiles were output during the run
297(profiles to be output have to be selected with the parameter <a href="#data_output_pr">data_output_pr</a>).
298For example if <b>data_output_pr</b> = <span style="font-style: italic;">'u'</span>, <span style="font-style: italic;">'v'</span> was assigned,
299then
300the plot only consists of one panel, since no profiles of the potential
301temperature were output. On the other hand, if profiles were assigned
302to <b>data_output_pr </b>whose names do not appear in <b>cross_profiles</b>,
303then the respective profile data are output (<a href="chapter_3.4.html#PLOT1D_DATA">PLOT1D_DATA</a>)
304but they are not drawn in the plot. <br> </p>
305The arrangement of the panels in the plot can be controlled
306with the parameters <a href="#profile_columns">profile_columns</a>
307and <a href="#profile_rows">profile_rows</a>.
308Up to 100 panels systems are allowed in a plot (however, they may be
309distributed on several pages).</td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="cross_xtext"></a><b>cross_xtext</b></p>
310</td> <td style="vertical-align: top;">C*40&nbsp;
311<br>&nbsp;&nbsp; (100)</td> <td style="vertical-align: top;">see right<br> </td>
312<td style="vertical-align: top;"> <p>x-axis labels
313of vertical profile coordinate systems to be
314plotted with <span style="font-weight: bold;">profil</span>.&nbsp;
315</p> <p>This parameter only applies for &nbsp;<a href="chapter_4.2.html#data_output_format">data_output_format</a>
316= <span style="font-style: italic;">'profil'</span>.</p><p>The
317default assignment is:&nbsp; </p> <p><b>cross_xtext</b>
318=&nbsp; </p> <ul> <p><span style="font-style: italic;">'wind speed in
319ms&gt;-&gt;1',&nbsp; </span><br style="font-style: italic;"> <span style="font-style: italic;">'pot. temperature in
320K',&nbsp; </span><br style="font-style: italic;">
321<span style="font-style: italic;">'heat flux in K
322ms&gt;-&gt;1',&nbsp; </span><br style="font-style: italic;"> <span style="font-style: italic;">'momentum flux in
323m&gt;2s&gt;2',&nbsp; </span><br style="font-style: italic;"> <span style="font-style: italic;">'eddy diffusivity in
324m&gt;2s&gt;-&gt;1',&nbsp; </span><br style="font-style: italic;"> <span style="font-style: italic;">'mixing length in m',</span>&nbsp;
325<br>14 * <span style="font-style: italic;">' '</span></p>
326</ul> <p>This parameter can be used to assign x-axis
327labels to vertical
328profiles to be plotted with the plot software <span style="font-weight: bold;">profil </span>(for output
329of vertical
330profile data see <a href="#data_output_pr">data_output_pr</a>).<br>
331The labels are assigned to those coordinate systems (panels) defined by
332<a href="#cross_profiles">cross_profiles</a>
333according to their respective order (compare the default values of <b>cross_xtext</b>
334and <b>cross_profiles</b>). </p> <p>Umlauts
335are possible (write &ldquo; in front of, similar to TeX), as
336well as super- and subscripts (use "&gt;" or "&lt;" in front of
337each
338character), special characters etc. (see UNIRAS manuals) when using the
339plot software <a href="http://www.muk.uni-hannover.de/institut/software/profil_beschreibung.html#chapter3.2.6">profil</a>.</p>
340</td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="cycle_mg"></a><b>cycle_mg</b></p>
341</td> <td style="vertical-align: top;">C*1</td>
342<td style="vertical-align: top;"><i>'w'</i></td>
343<td style="vertical-align: top;"> <p>Type of cycle
344to be used with the multi-grid method.&nbsp; </p> <p>This
345parameter determines which type of cycle is applied in
346the multi-grid method used for solving the Poisson equation for
347perturbation pressure (see <a href="#psolver">psolver</a>).
348It defines in which way it is switched between the fine and coarse
349grids. So-called v- and w-cycles are realized (i.e. <b>cycle_mg</b>
350may be assigned the values <i>'v'</i> or <i>'w'</i>).
351The
352computational cost of w-cycles is much higher than that of v-cycles,
353however, w-cycles give a much better convergence. </p> </td>
354</tr> <tr> <td style="vertical-align: top;"><p><a name="data_output"></a><b>data_output</b></p>
355</td> <td style="vertical-align: top;">C * 10 (100)<br>
356</td> <td style="vertical-align: top;"><span style="font-style: italic;">100 * ' '</span><br>
357</td> <td style="vertical-align: top;">Quantities
358for which 2d cross section and/or 3d volume data are to be output.<br><br>PALM
359allows the output of instantaneous data as well as of temporally
360averaged data which is steered by the strings assigned to this
361parameter (see below).<br><br>By default, cross section
362data are output (depending on the selected cross sections(s), see
363below)&nbsp; to local files <a href="chapter_3.4.html#DATA_2D_XY_NETCDF">DATA_2D_XY_NETCDF</a>,
364<a href="chapter_3.4.html#DATA_2D_XZ_NETCDF">DATA_2D_XZ_NETCDF</a>
365and/or <a href="chapter_3.4.html#DATA_2D_YZ_NETCDF">DATA_2D_YZ_NETCDF</a>.
366Volume data are output to file <a href="chapter_3.4.html#DATA_3D_NETCDF">DATA_3D_NETCDF</a>.
367If the user has switched on the output of temporally averaged data,
368these are written seperately to local files <a href="chapter_3.4.html#DATA_2D_XY_AV_NETCDF">DATA_2D_XY_AV_NETCDF</a>,
369<a href="chapter_3.4.html#DATA_2D_XZ_AV_NETCDF">DATA_2D_XZ_AV_NETCDF</a>,
370<a href="chapter_4.3.html#DATA_2D_YZ_AV_NETCDF">DATA_2D_YZ_AV_NETCDF</a>,
371and <a href="chapter_3.4.html#DATA_3D_AV_NETCDF">DATA_3D_AV_NETCDF</a>,
372respectively.<br><br>The
373filenames already suggest that all files have NetCDF format.
374Informations about the file content (kind of quantities, array
375dimensions and grid coordinates) are part of the self describing NetCDF
376format and can be extracted from the NetCDF files using the command
377"ncdump -c &lt;filename&gt;". See chapter <a href="chapter_4.5.1.html">4.5.1</a> about processing
378the PALM NetCDF data.<br><br>The following quantities are
379available for output by default (quantity names ending with '*' are only allowed for the output of horizontal cross sections):<br><br><table style="text-align: left; width: 576px; height: 481px;" border="1" cellpadding="2" cellspacing="2"><tbody><tr><td style="width: 106px;"><span style="font-weight: bold;">quantity
380name</span></td><td style="width: 196px;"><span style="font-weight: bold;">meaning</span></td><td><span style="font-weight: bold;">unit</span></td><td><span style="font-weight: bold;">remarks</span></td></tr><tr><td style="width: 106px;"><span style="font-style: italic;">e</span></td><td style="width: 196px;">SGS TKE</td><td>m<sup>2</sup>/s<sup>2</sup></td><td></td></tr><tr><td style="width: 106px; vertical-align: top;"><span style="font-style: italic;">lwp*</span></td><td style="width: 196px; vertical-align: top;">liquid water path</td><td style="vertical-align: top;">m</td><td style="vertical-align: top;">only horizontal cross section
381is allowed,&nbsp;requires <a href="chapter_4.1.html#cloud_physics">cloud_physics</a>
382= <span style="font-style: italic;">.TRUE.</span></td></tr><tr><td style="width: 106px; vertical-align: top;"><span style="font-style: italic;">p</span></td><td style="width: 196px; vertical-align: top;">perturpation
383pressure</td><td style="vertical-align: top;">N/m<sup>2</sup>,
384Pa</td><td style="vertical-align: top;"></td></tr><tr><td style="width: 106px; vertical-align: top;"><span style="font-style: italic;">pc</span></td><td style="width: 196px; vertical-align: top;">particle/droplet
385concentration</td><td style="vertical-align: top;">#/gridbox</td><td style="vertical-align: top;">requires that particle
386advection is switched on by <span style="font-weight: bold;">mrun</span>-option
387"-p particles"</td></tr><tr><td style="width: 106px; vertical-align: top;"><span style="font-style: italic;">pr</span></td><td style="width: 196px; vertical-align: top;">mean
388particle/droplet radius </td><td style="vertical-align: top;">m</td><td style="vertical-align: top;">requires that particle
389advection is switched on by <span style="font-weight: bold;">mrun</span>-option
390"-p particles"</td></tr><tr><td style="vertical-align: top;"><span style="font-style: italic;">pra*</span></td><td style="vertical-align: top;">precipitation amount</td><td style="vertical-align: top;">mm</td><td style="vertical-align: top;">only horizontal cross section
391is allowed,&nbsp;requires&nbsp;<a href="chapter_4.1.html#precipitation">precipitation</a>
392= <span style="font-style: italic;">.TRUE., </span>time interval on which amount refers to is defined by <a href="#precipitation_amount_interval">precipitation_amount_interval</a></td></tr><tr><td style="vertical-align: top;"><span style="font-style: italic;">prr*</span></td><td style="vertical-align: top;">precipitation rate</td><td style="vertical-align: top;">mm/s</td><td style="vertical-align: top;">only horizontal cross section
393is allowed,&nbsp;requires&nbsp;<a href="chapter_4.1.html#precipitation">precipitation</a>
394= <span style="font-style: italic;">.TRUE.</span></td></tr><tr><td style="width: 106px; vertical-align: top;"><span style="font-style: italic;">pt</span></td><td style="width: 196px; vertical-align: top;">potential
395temperature<br></td><td style="vertical-align: top;">K</td><td style="vertical-align: top;"></td></tr><tr><td style="width: 106px; vertical-align: top;"><span style="font-style: italic;">q</span></td><td style="width: 196px; vertical-align: top;">specific humidity
396(or total water content, if cloud physics is switched on)</td><td style="vertical-align: top;">kg/kg</td><td style="vertical-align: top;">requires <a href="chapter_4.1.html#moisture">moisture</a> = <span style="font-style: italic;">.TRUE.</span></td></tr><tr><td style="width: 106px; vertical-align: top;"><span style="font-style: italic;">ql</span></td><td style="width: 196px; vertical-align: top;">liquid water
397content</td><td style="vertical-align: top;">kg/kg</td><td style="vertical-align: top;">requires <a href="chapter_4.1.html#cloud_physics">cloud_physics</a>
398= <span style="font-style: italic;">.TRUE.</span>
399or <a href="chapter_4.1.html#cloud_droplets">cloud_droplets</a>
400= <span style="font-style: italic;">.TRUE.</span></td></tr><tr><td style="width: 106px; vertical-align: top;"><span style="font-style: italic;">ql_c</span></td><td style="width: 196px; vertical-align: top;">change in liquid
401water content due to condensation/evaporation during last timestep</td><td style="vertical-align: top;">kg/kg</td><td style="vertical-align: top;">requires <a href="chapter_4.1.html#cloud_droplets">cloud_droplets</a>
402= <span style="font-style: italic;">.TRUE.</span></td></tr><tr><td style="width: 106px; vertical-align: top;"><span style="font-style: italic;">ql_v</span></td><td style="width: 196px; vertical-align: top;">volume of liquid
403water</td><td style="vertical-align: top;">m<sup>3</sup>/gridbox</td><td style="vertical-align: top;">requires <a href="chapter_4.1.html#cloud_droplets">cloud_droplets</a>
404= <span style="font-style: italic;">.TRUE.</span></td></tr><tr><td style="width: 106px; vertical-align: top;"><span style="font-style: italic;">ql_vp</span></td><td style="width: 196px; vertical-align: top;">weighting factor</td><td style="vertical-align: top;"></td><td style="vertical-align: top;">requires <a href="chapter_4.1.html#cloud_droplets">cloud_droplets</a>
405= <span style="font-style: italic;">.TRUE.</span></td></tr><tr><td style="width: 106px; vertical-align: top;"><span style="font-style: italic;">qv</span></td><td style="width: 196px; vertical-align: top;">water vapor
406content (specific humidity)</td><td style="vertical-align: top;">kg/kg</td><td style="vertical-align: top;">requires <a href="chapter_4.1.html#cloud_physics">cloud_physics</a>
407= <span style="font-style: italic;">.TRUE.</span></td></tr><tr><td style="width: 106px; vertical-align: top;"><span style="font-style: italic;">s</span></td><td style="width: 196px; vertical-align: top;">concentration of
408the scalar</td><td style="vertical-align: top;">1/m<sup>3</sup></td><td style="vertical-align: top;">requires&nbsp;<a href="chapter_4.1.html#passive_scalar">passive_scalar</a>
409= <span style="font-style: italic;">.TRUE.</span></td></tr><tr><td style="width: 106px; vertical-align: top;"><span style="font-style: italic;">t*</span></td><td style="width: 196px; vertical-align: top;">(near surface)
410characteristic temperature</td><td style="vertical-align: top;">K</td><td style="vertical-align: top;">only horizontal cross section
411is allowed</td></tr><tr><td style="width: 106px; vertical-align: top;"><span style="font-style: italic;">u</span></td><td style="width: 196px; vertical-align: top;">u-component of
412the velocity</td><td style="vertical-align: top;">m/s</td><td style="vertical-align: top;"></td></tr><tr><td style="width: 106px; vertical-align: top;"><span style="font-style: italic;">u*</span></td><td style="width: 196px; vertical-align: top;">(near surface)
413friction velocity</td><td style="vertical-align: top;">m/s</td><td style="vertical-align: top;">only horizontal cross section
414is allowed</td></tr><tr><td style="width: 106px; vertical-align: top;"><span style="font-style: italic;">v</span></td><td style="width: 196px; vertical-align: top;">v-component of
415the velocity</td><td style="vertical-align: top;">m/s</td><td style="vertical-align: top;"></td></tr><tr><td style="width: 106px; vertical-align: top;"><span style="font-style: italic;">vpt</span></td><td style="width: 196px; vertical-align: top;">virtual potential
416temperature</td><td style="vertical-align: top;">K</td><td style="vertical-align: top;">requires <a href="chapter_4.1.html#moisture">moisture</a> = <span style="font-style: italic;">.TRUE.</span></td></tr><tr><td style="width: 106px; vertical-align: top;"><span style="font-style: italic;">w</span></td><td style="width: 196px; vertical-align: top;">w-component of
417the velocity</td><td style="vertical-align: top;">m/s</td><td style="vertical-align: top;"></td></tr><tr><td style="vertical-align: top;"><span style="font-style: italic;">z0*</span></td><td style="vertical-align: top;">roughness length</td><td style="vertical-align: top;">m</td><td></td></tr></tbody></table><br>Multiple
418quantities can be assigned, e.g. <span style="font-weight: bold;">data_output</span>
419= <span style="font-style: italic;">'e'</span>, <span style="font-style: italic;">'u'</span>, <span style="font-style: italic;">'w'</span>.<br><br>By
420assigning the pure strings from the above table, 3d volume data is
421output. Cross section data can be output by appending the string <span style="font-style: italic;">'_xy'</span>, <span style="font-style: italic;">'_xz'</span>, or <span style="font-style: italic;">'_yz'</span> to the
422respective quantities. Time averaged&nbsp;output is created by
423appending the string <span style="font-style: italic;">'_av'
424</span>(for
425cross section data, this string must be appended after the cross
426section string). Cross section data can also be (additionally) averaged
427along the direction normal to the respective section (see below).
428Assignments of quantities can be given in arbitrary
429order:<br><br>Example:<br><br><div style="margin-left: 40px;"><span style="font-weight: bold;">data_output</span> = <span style="font-style: italic;">'u'</span>, <span style="font-style: italic;">'pt_xz_av'</span>, <span style="font-style: italic;">'w_xy'</span>, <span style="font-style: italic;">'u_av'</span>.<br></div><br>This
430example will create the following output: instantaneous 3d volume data
431of u-velocity component (by default on file DATA_3D_NETCDF), temporally
432averaged 3d volume data of u-velocity component (by default on file
433DATA_3D_AV_NETCDF), instantaneous horizontal cross section data of
434w-velocity component (by default on file DATA_2D_XY_NETCDF), and
435temporally averaged vertical cross section data of potential
436temperature (by default on file DATA_2D_XZ_AV_NETCDF).<br><br>The
437user is allowed to extend the above list of quantities by defining his
438own output quantities (see the user-parameter <a href="chapter_4.3.html#data_output_user">data_output_user</a>).<br><br>The
439time interval of the output times is determined via <a href="#dt_data_output">dt_data_output</a>.
440This is valid for all types of output quantities by default. Individual
441time intervals for instantaneous &nbsp;(!) 3d and section data can
442be
443declared using <a href="#dt_do3d">dt_do3d</a>, <a href="#dt_do2d_xy">dt_do2d_xy</a>, <a href="#dt_do2d_xz">dt_do2d_xz</a>, and <a href="#dt_do2d_yz">dt_do2d_yz</a>.<br><br>Also,
444an individual time interval for output of temporally averaged data can
445be assigned using parameter <a href="#dt_data_output_av">dt_data_output_av</a>.
446This applies to both 3d volume and cross section data. The length of
447the averaging interval is controlled via parameter <a href="#averaging_interval">averaging_interval</a>.<br><br>The
448parameter <a href="#skip_time_data_output">skip_time_data_output</a>
449can be used to shift data output activities for a given time interval.
450Individual intervals can be set using <a href="#skip_time_do3d">skip_time_do3d</a>,
451<a href="#skip_time_do2d_xy">skip_time_do2d_xy</a>, <a href="#skip_time_do2d_xz">skip_time_do2d_xz</a>, <a href="#skip_time_do2d_yz">skip_time_do2d_yz</a>, and <a href="#skip_time_data_output_av">skip_time_data_output_av</a>.<br><p>With
452the parameter <a href="chapter_4.2.html#nz_do3d">nz_do3d</a>&nbsp;
453the output can be limited in the vertical direction up to a certain
454grid point.<br> </p> Cross sections extend through the
455total model
456domain. In the two horizontal directions all grid points with 0
457&lt;= i
458&lt;= nx+1 and 0 &lt;= j
459&lt;= ny+1 are output so that in case of cyclic boundary conditions
460the
461complete total domain is represented. The location(s) of the cross
462sections can be defined with parameters <a href="#section_xy">section_xy</a>,
463<a href="#section_xz">section_xz</a>, and <a href="#section_yz">section_yz</a>. Assigning <span style="font-weight: bold;">section_..</span> = <span style="font-style: italic;">-1</span>
464causes&nbsp;the output data to be averaged along the direction
465normal to the respective section.<br><br><br><span style="font-weight: bold;">Output of user defined quantities:</span><br><br>Beside
466the standard quantities from the above list, the user can output any
467other quantities. These have to be defined and calculated within the
468user-defined code (see <a href="chapter_3.5.4.html">3.5.4</a>).
469They can be selected for output with the user-parameter <a href="chapter_4.3.html#data_output_user">data_output_user</a>
470for which the same rules apply as for <span style="font-weight: bold;">data_output</span>.
471Output of the user defined quantities (time interval, averaging,
472selection of cross sections, etc.) is controlled with the parameters
473listed above and data are written to the same file(s) as the standard
474quantities.<br><br><p style="font-weight: bold;">Output
475on parallel machines:</p><p>
476By default, with parallel runs, processors output only data
477of their respective subdomains into seperate local files (file names
478are
479constructed by appending the four digit processor ID, e.g.
480&lt;filename&gt;_0000, &lt;filename&gt;_0001, etc.).
481After PALM has
482finished, the contents of these individual
483files are sampled into one final file<span style="font-weight: bold;"></span>
484using the program <tt><font style="font-size: 11pt;" size="2">combine_plot_fields.x</font></tt>
485(to be started e.g. by a suitable OUTPUT command in the <span style="font-weight: bold;">mrun</span>
486configuration file).</p> <p>Alternatively, PALM is able to
487collect all grid points of a
488cross section on PE0 before output is done. In this case only
489one&nbsp;
490output file (DATA_2D_XY_NETCDF, etc.) is created and <tt><font style="font-size: 11pt;" size="2">combine_plot_fields.x</font></tt>
491does not have to be called. In case of very large numbers of horizontal
492gridpoints, sufficient
493memory is required on PE0.&nbsp; This method can be used by
494assigning <a href="chapter_4.2.html#data_output_2d_on_each_pe">data_output_2d_on_each_pe</a>
495= <i>.F.</i>.</p><p>3d volume data output is
496always handled seperately by each processor so that <span style="font-family: monospace;">combine_plot_fields.x</span>
497has to be called anyway after PALM has been finished.</p><p><br><span style="font-weight: bold;">Old formats:</span></p>
498<p>Beside
499the NetCDF format,&nbsp;2d cross section data and 3d volume data
500can
501also be output, for historical reasons, in a different (binary) format
502using parameter <a href="#data_output_format">data_output_format</a>.</p><p>By
503assigning <span style="font-weight: bold;">data_output_format
504</span>= <span style="font-style: italic;">'avs'</span>,
505the 3d volume data is output to the local file <a href="chapter_3.4.html#PLOT3D_DATA">PLOT3D_DATA</a>.
506Output is in FORTRAN binary format&nbsp;readable by
507the plot software <span style="font-weight: bold;">AVS</span>.&nbsp;
508The order of data on the file follows the order used in the assignment
509for <b>data_output</b> (e.g. <b>data_output</b>
510= <span style="font-style: italic;">'p'</span>, <span style="font-style: italic;">'v'</span>,...&nbsp;
511means that the file starts with the pressure data, followed by the
512v-component of the velocity, etc.). Both instantaneous and time
513averaged data are written on this file! Additional to this file, PALM
514creates
515a second binary file (local name <a href="chapter_3.4.html#PLOT3D_COOR">PLOT3D_COOR</a>)
516with coordinate information needed by <span style="font-weight: bold;">AVS</span>.
517As third and
518fourth file two ASCII files are created (AVS-FLD-format, local name <a href="chapter_3.4.html#PLOT3D_FLD">PLOT3D_FLD</a>
519and <a href="chapter_3.4.html#PLOT3D_FLD_COOR">PLOT3D_FLD_COOR</a>),
520which describe the contents of the data file and/or coordinate file
521and are used by AVS. However, AVS expects the content description in
522one file. This needs the local file PLOT3D_FLD_COOR to be appended to
523the file
524PLOT3D_FLD (by suitable OUTPUT command in the <span style="font-weight: bold;">mrun</span>
525configuration file: &ldquo;<span style="font-family: monospace;">cat
526PLOT3D_FLD_COOR &gt;&gt; PLOT3D_FLD</span>&rdquo;)
527after PALM has
528finished.&nbsp;To reduce the amount of data, output to this file
529can be done
530in
531compressed form (see <a href="chapter_4.2.html#do3d_compress">do3d_compress</a>).
532Further details about plotting 3d volume data with <span style="font-weight: bold;">AVS </span>can be found in
533<a href="chapter_4.5.5.html">chapter
5344.5.5</a>.</p>By assigning <span style="font-weight: bold;">data_output_format </span>=
535<span style="font-style: italic;">'iso2d'</span>,
536the cross section data is output to the local files <a href="chapter_3.4.html#PLOT2D_XY">PLOT2D_XY</a>, <a href="chapter_3.4.html#PLOT2D_XZ">PLOT2D_XZ</a>, and <a href="chapter_3.4.html#PLOT2D_YZ">PLOT2D_YZ</a>.
537Output is in FORTRAN binary format&nbsp;readable by
538the plot software&nbsp;<span style="font-weight: bold;">iso2d</span>.&nbsp;
539The order of data on the files follows the order used in the assignment
540for <b>data_output</b> (e.g. <b>data_output</b>
541= <span style="font-style: italic;">'p_xy'</span>, <span style="font-style: italic;">'v_xy_av'</span>,...&nbsp;
542means that the file containing the horizontal cross section data starts
543with the instantaneous pressure data, followed by the
544temporally averaged v-component of the velocity, etc.). Both
545instantaneous and time averaged data are written on this
546file!Additional to these binary files, PALM
547creates NAMELIST parameter files
548(local names <a href="chapter_3.4.html#PLOT2D_XY_GLOBAL">PLOT2D_XY_GLOBAL</a>,
549<a href="chapter_3.4.html#PLOT2D_XY_LOCAL">PLOT2D_XY_LOCAL</a>,
550<a href="chapter_3.4.html#PLOT2D_XZ_GLOBAL">PLOT2D_XZ_GLOBAL</a>,
551<a href="chapter_3.4.html#PLOT2D_XZ_LOCAL">PLOT2D_XZ_LOCAL</a>,
552<a href="chapter_3.4.html#PLOT2D_YZ_GLOBAL">PLOT2D_YZ_GLOBAL</a>,
553<a href="chapter_3.4.html#PLOT2D_YZ_LOCAL">PLOT2D_YZ_LOCAL</a>)
554which can be used as parameter input files for the plot software <a href="http://www.muk.uni-hannover.de/institut/software/iso2d_beschreibung.html">iso2d</a>.
555That needs local files with suffix _LOCAL to be appended to the
556respective files with suffix _GLOBAL (by
557suitable OUTPUT commands in the <span style="font-weight: bold;">mrun</span>
558configuration file, e.g.: &ldquo;<span style="font-family: monospace;">cat
559PLOT2D_XY_LOCAL &gt;&gt; PLOT2D_XY_GLOBAL</span>&rdquo;)
560after PALM has
561finished. Cross sections can be directly plotted with <span style="font-weight: bold;">iso2d</span> using the
562respective data and
563parameter file. The plot layout is steered via the parameter input
564file.
565The values of these <span style="font-weight: bold;">iso2d</span>
566parameters are determined by a set of mostly internal PALM parameters
567(exception: <a href="chapter_4.2.html#z_max_do2d">z_max_do2d</a>).
568All parameter values can be changed by editing the parameter input
569file.&nbsp;Further details about plotting 2d cross sections with <span style="font-weight: bold;">iso2d </span>can be found
570in <a href="chapter_4.5.4.html">chapter
5714.5.4</a>.<br><br><span style="font-weight: bold;">Important:</span><br>There
572is no guarantee that iso2d- and avs-output will be available in future
573PALM versions (later than 3.0). </td> </tr> <tr> <td style="vertical-align: top;"><a name="data_output_format"></a><span style="font-weight: bold;">data_output_format</span><br>
574</td> <td style="vertical-align: top;">C * 10 (10) </td>
575<td style="vertical-align: top;"><span style="font-style: italic;">'netcdf'</span> </td>
576<td style="vertical-align: top;">Format of output data.<br><br>By
577default, all data (profiles, time
578series, spectra, particle data, cross sections, volume data) are output
579in NetCDF format (see chapter <a href="chapter_4.5.1.html">4.5.1</a>).
580Exception: restart data (local files <a href="chapter_3.4.html#BININ">BININ</a>, <a href="chapter_3.4.html#BINOUT">BINOUT</a>, <a href="chapter_3.4.html#PARTICLE_RESTART_DATA_IN">PARTICLE_RESTART_DATA_IN</a>,
581<a href="chapter_3.4.html#PARTICLE_RESTART_DATA_OUT">PARTICLE_RESTART_DATA_OUT</a>)
582are always output in FORTRAN binary format.<br><br>The
583numerical precision of the NetCDF output is determined with parameter <a href="#chapter_4.1.html#netcdf_precision">netcdf_precision</a>.<br><br>The
584maximum file size for NetCDF files is 2 GByte by default. Use the
585parameter <a href="#netcdf_64bit">netcdf_64bit</a>
586if larger files have to be created.<br><br>For historical
587reasons, other data formats are still available. Beside 'netcdf', <span style="font-weight: bold;">data_output_format</span>
588may be assigned the following values:<br><br><table style="text-align: left; width: 594px; height: 104px;" border="1" cellpadding="2" cellspacing="2"><tbody><tr><td style="vertical-align: top;"><span style="font-style: italic;">'profil'</span></td><td>output
589of profiles,&nbsp;time series and spectra in ASCII format to be
590read by the graphic software <span style="font-weight: bold;">profil
591</span>(see chapters <a href="chapter_4.5.2.html">4.5.2</a>,
592<a href="#chapter_4.5.3.html">4.5.3</a>)</td></tr><tr><td style="vertical-align: top;"><span style="font-style: italic;">'iso2d'</span></td><td>output
593of 2d cross-sections in FORTRAN binary format to be read by the graphic
594software <span style="font-weight: bold;">iso2d</span>
595(see chapter <a href="chapter_4.5.4.html">4.5.4</a>)</td></tr><tr><td style="vertical-align: top;"><span style="font-style: italic;">'avs'</span></td><td>output
596of 3d volume data in FORTRAN binary format to be read by the graphic
597software <span style="font-weight: bold;">AVS</span>
598(see chapter <a href="chapter_4.5.5.html">4.5.5</a>)</td></tr></tbody></table><br>Multiple
599values can be assigned to <span style="font-weight: bold;">data_output_format</span>,
600i.e. if the user wants to have both the "old" data format suitable for <span style="font-weight: bold;">iso2d</span> as well as
601cross section data in NetCDF format, then <span style="font-weight: bold;">data_output_format</span> =
602<span style="font-style: italic;">'iso2d'</span>, <span style="font-style: italic;">'netcdf'</span> has to be
603assigned.<br><br><span style="font-weight: bold;">Warning:</span>
604There is no guarantee that the "old" formats will be available in
605future PALM versions (beyond 3.0)!<br> </td> </tr> <tr>
606<td style="vertical-align: top;"> <p><a name="data_output_pr"></a><b>data_output_pr</b></p>
607</td> <td style="vertical-align: top;">C *
60810&nbsp; <br>
609(100)</td> <td style="vertical-align: top;"><i>100
610* ' '</i></td> <td style="vertical-align: top;">
611<p>Quantities for which vertical profiles (horizontally averaged)
612are to be output.&nbsp; </p> <p>By default vertical
613profile data is output to the local file <a href="chapter_3.4.html#DATA_1D_PR_NETCDF">DATA_1D_PR_NETCDF</a>.
614The file's format is NetCDF.&nbsp; Further details about processing
615NetCDF data are given in chapter <a href="chapter_4.5.1.html">4.5.1</a>.</p><p>For
616historical reasons, data can also be output in ASCII-format on local
617file <a href="chapter_3.4.html#PLOT1D_DATA">PLOT1D_DATA</a>
618which is readable by the graphic software <span style="font-weight: bold;">profil</span>. See
619parameter <a href="#data_output_format">data_output_format</a>
620for defining the format in which data shall be output.<br> </p>
621<p>For horizontally averaged vertical
622profiles always <span style="font-weight: bold;">all</span>
623vertical
624grid points (0 &lt;= k &lt;= nz+1) are output to file. Vertical
625profile data refers to the total domain but profiles for subdomains can
626also be output (see <a href="chapter_4.1.html#statistic_regions">statistic_regions</a>).&nbsp;
627</p> <p>The temporal interval of the output times of
628profiles is
629assigned via the parameter <a href="chapter_4.2.html#dt_dopr">dt_dopr</a>.
630Within the file <a href="chapter_3.4.html#PLOT1D_DATA">PLOT1D_DATA</a>,
631the profiles are ordered with respect to their
632output times.</p><p>Profiles can also be temporally
633averaged (see <a href="chapter_4.2.html#averaging_interval_pr">averaging_interval_pr</a>).&nbsp;<br>
634</p> <p>The following list shows the values which can be
635assigned to <span style="font-weight: bold;">data_output_pr</span>.
636The profile data is either defined on
637u-v-levels (variables marked in <font color="#ff6600">red</font>)
638or
639on w-levels (<font color="#33ff33">green</font>).
640According to this,
641the
642z-coordinates of the individual profiles vary. Beyond that, with a
643Prandtl layer switched on (<a href="chapter_4.1.html#prandtl_layer">prandtl_layer</a>)
644the lowest output
645level is z = zu(1) instead of z = zw(0) for profiles <i>w''
646u'',w''v"</i>, <i>wu</i> and <i>wv</i>
647.&nbsp; <br> </p> <table style="text-align: left; width: 100%;" cellpadding="2" cellspacing="2"> <tbody> <tr> <td style="vertical-align: top;"><font color="#ff6600"><i>u</i></font></td>
648<td style="vertical-align: top;">u-component of the
649velocity (in m/s).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#ff6600"><i>v</i></font></td>
650<td style="vertical-align: top;">v-component of the
651velocity (in m/s).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#33ff33"><i>w</i></font></td>
652<td style="vertical-align: top;">w-component of the
653velocity (in m/s).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#ff6600"><i>pt</i></font></td>
654<td style="vertical-align: top;">Potential temperature (in
655K).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#ff6600"><i>vpt</i></font></td>
656<td style="vertical-align: top;">Virtual potential
657temperature (in K).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#ff6600"><i>lpt</i></font></td>
658<td style="vertical-align: top;">Potential liquid water
659temperature (in K).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#ff6600"><i>q</i></font></td>
660<td style="vertical-align: top;">Total water content
661(in kg/kg).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#ff6600"><i>qv</i></font></td>
662<td style="vertical-align: top;">Specific humidity (in
663kg/kg).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#ff6600"><i>ql</i></font></td>
664<td style="vertical-align: top;">Liquid water content
665(in kg/kg).</td> </tr> <tr> <td style="vertical-align: middle;"><font color="#ff6600">s</font></td>
666<td style="vertical-align: top;">Scalar concentration (in
667kg/m<sup>3</sup>).</td> </tr> <tr> <td style="vertical-align: middle;"><font color="#ff6600"><i>e</i></font></td>
668<td style="vertical-align: top;">Turbulent kinetic energy
669(TKE, subgrid-scale) (in m<sup>2</sup>/s<sup>2</sup>).</td>
670</tr> <tr> <td style="vertical-align: middle;"><font color="#ff6600"><i>e*</i></font></td>
671<td style="vertical-align: top;">Perturbation energy
672(resolved) (in m<sup>2</sup>/s<sup>2</sup>).</td>
673</tr> <tr> <td style="vertical-align: middle;"><font color="#ff6600"><i>km</i></font></td>
674<td style="vertical-align: top;">Eddy diffusivity for
675momentum (in m<sup>2</sup>/s).</td> </tr> <tr>
676<td style="vertical-align: middle;"><font color="#ff6600"><i>kh</i></font></td>
677<td style="vertical-align: top;">Eddy diffusivity for heat
678(in m<sup>2</sup>/s).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#ff6600"><i>l</i></font></td>
679<td style="vertical-align: top;">Mixing length (in m).</td>
680</tr> <tr> <td style="vertical-align: middle;"><font color="#33ff33"><i>w"u"</i></font></td>
681<td style="vertical-align: top;">u-component of the
682subgrid-scale vertical momentum flux (in m<sup>2</sup>/s<sup>2</sup>).</td>
683</tr> <tr> <td style="vertical-align: middle;"><font color="#33ff33"><i>w*u*</i></font></td>
684<td style="vertical-align: top;">u-component of the
685resolved vertical momentum flux (in m<sup>2</sup>/s<sup>2</sup>).</td>
686</tr> <tr> <td style="vertical-align: middle;"><font color="#33ff33"><i>wu</i></font></td>
687<td style="vertical-align: top;">u-component of the total
688vertical momentum flux (<i>w"u"</i> + <i>w*u*</i>)
689(in m<sup>2</sup>/s<sup>2</sup>).</td> </tr>
690<tr> <td style="vertical-align: middle;"><font color="#33ff33"><i>w"v"</i></font></td>
691<td style="vertical-align: top;">v-component of the
692subgrid-scale vertical momentum flux (in m<sup>2</sup>/s<sup>2</sup>).</td>
693</tr> <tr> <td style="vertical-align: middle;"><font color="#33ff33"><i>w*v*</i></font></td>
694<td style="vertical-align: top;">v-component of the
695resolved vertical momentum flux (in m<sup>2</sup>/s<sup>2</sup>).</td>
696</tr> <tr> <td style="vertical-align: middle;"><font color="#33ff33"><i>wv</i></font></td>
697<td style="vertical-align: top;">v-component of the total
698vertical momentum flux (<i>w"v"</i> + <i>w*v*</i>)
699(in m<sup>2</sup>/s<sup>2</sup>).</td> </tr>
700<tr> <td style="vertical-align: top;"><font color="#33ff33"><i>w"pt"</i></font></td>
701<td style="vertical-align: top;">Subgrid-scale vertical
702sensible heat flux (in K m/s).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#33ff33"><i>w*pt*</i></font></td>
703<td style="vertical-align: top;">Resolved vertical
704sensible
705heat flux (in K m/s).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#33ff33"><i>wpt</i></font></td>
706<td style="vertical-align: top;">Total vertical sensible
707heat flux (<i>w"pt"</i> + <i>w*pt*</i>)
708(in K
709m/s).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#33ff33"><i>w*pt*BC</i></font></td>
710<td style="vertical-align: top;">Subgrid-scale vertical
711sensible heat flux using the
712Bott-Chlond scheme (in K m/s).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#33ff33"><i>wptBC</i></font></td>
713<td style="vertical-align: top;">Total vertical sensible
714heat flux using the Bott-Chlond scheme
715(<i>w"pt"</i>
716+ <i>w*pt*BC</i>) (in K m/s).</td> </tr> <tr>
717<td style="vertical-align: top;"><font color="#33ff33"><i>w"vpt"</i></font></td>
718<td style="vertical-align: top;">Subgrid-scale vertical
719buoyancy flux (in K m/s).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#33ff33"><i>w*pt*</i></font></td>
720<td style="vertical-align: top;">Resolved vertical
721buoyancy
722flux (in K m/s).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#33ff33"><i>wvpt</i></font></td>
723<td style="vertical-align: top;">Total vertical buoyancy
724flux (w"vpt" + w*vpt*) (in K m/s).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#33ff33"><i>w"q"</i></font></td>
725<td style="vertical-align: top;">Subgrid-scale vertical
726water flux (in kg/kg m/s).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#33ff33"><i>w*q*</i></font></td>
727<td style="vertical-align: top;">Resolved vertical water
728flux (in kg/kg m/s).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#33ff33"><i>wq</i></font></td>
729<td style="vertical-align: top;">Total vertical water flux
730(w"q" + w*q*) (in kg/kg m/s).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#33ff33"><i>w"qv"</i></font></td>
731<td style="vertical-align: top;">Subgrid-scale vertical
732latent heat flux (in kg/kg m/s).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#33ff33"><i>w*qv*</i></font></td>
733<td style="vertical-align: top;">Resolved vertical latent
734heat flux (in kg/kg m/s).</td> </tr> <tr> <td style="vertical-align: top;"><font color="#33ff33"><i>wqv</i></font></td>
735<td style="vertical-align: top;">Total vertical latent
736heat
737flux (w"qv" + w*qv*) (in kg/kg m/s).</td> </tr> <tr>
738<td style="vertical-align: middle;"><font color="#33ff33"><i>w"s"</i></font></td>
739<td style="vertical-align: top;">Subgrid-scale vertical
740scalar concentration flux (in kg/m<sup>3 </sup>m/s).</td>
741</tr> <tr> <td style="vertical-align: middle;"><font color="#33ff33"><i>w*s*</i></font></td>
742<td style="vertical-align: top;">Resolved vertical scalar
743concentration flux (in kg/m<sup>3</sup>)</td> </tr>
744<tr> <td style="vertical-align: middle;"><font color="#33ff33"><i>ws</i></font></td>
745<td style="vertical-align: top;">Total vertical scalar
746concentration flux (w"s" + w*s*) (in kg/m<sup>3 </sup>m/s).</td>
747</tr> <tr> <td style="vertical-align: top;"><font color="#33ff33"><i>w*e*</i></font></td>
748<td style="vertical-align: top;">Vertical flux of
749perturbation energy (resolved)</td> </tr> <tr> <td style="vertical-align: top;"><font color="#ff6600"><i>u*2</i></font></td>
750<td style="vertical-align: top;">Variance of the
751u-velocity
752component (resolved)</td> </tr> <tr> <td style="vertical-align: top;"><font color="#ff6600"><i>v*2</i></font></td>
753<td style="vertical-align: top;">Variance of the
754v-velocity
755component (resolved)</td> </tr> <tr> <td style="vertical-align: top;"><font color="#33ff33"><i>w*2</i></font></td>
756<td style="vertical-align: top;">Variance of the potential
757temperature (resolved)</td> </tr> <tr> <td style="vertical-align: top;"><font color="#ff6600"><i>pt*2</i></font></td>
758<td style="vertical-align: top;">Variance of the potential
759temperature (resolved)</td> </tr> <tr> <td style="vertical-align: top;"><font color="#33ff33"><i>w*3</i></font></td>
760<td style="vertical-align: top;">Third moment of the
761w-velocity component (resolved)</td> </tr> <tr> <td style="vertical-align: middle;"><font color="#33ff33"><i>Sw</i></font></td>
762<td style="vertical-align: top;">Skewness of the
763w-velocity
764component (resolved, S<sub>w</sub>
765= W<sup>3</sup>/(w<sup>2</sup>)<sup>1.5</sup>)</td>
766</tr> <tr> <td style="vertical-align: top;"><font color="#33ff33"><i>w*2pt*</i></font></td>
767<td style="vertical-align: top;">Third moment (resolved)</td>
768</tr> <tr> <td style="vertical-align: top;"><font color="#33ff33"><i>w*pt*2</i></font></td>
769<td style="vertical-align: top;">Third moment (resolved)</td>
770</tr> <tr> <td style="vertical-align: top;"><font color="#ff6666"><i>w*u*u*/dz</i></font></td>
771<td style="vertical-align: top;">Energy production by
772shear
773(resolved)</td> </tr> <tr> <td style="vertical-align: top;"><font color="#ff6666"><i>w*p*/dz</i></font></td>
774<td style="vertical-align: top;">Energy production by
775turbulent transport of pressure
776fluctuations (resolved)</td> </tr> <tr> <td style="vertical-align: top;"><font color="#ff6666"><i>w"e/dz</i></font></td>
777<td style="vertical-align: top;">Energy production by
778transport of resolved-scale TKE</td> </tr> </tbody>
779</table> <br>Beyond that, initial profiles (t=0) of some
780variables can be also be
781output (this output is only done once
782with the first plot output and not repeated with the profile output at
783later
784times). The names of these profiles result from the ones specified
785above leaded by a hash "#".&nbsp; Allowed values are:<br> <ul>
786<p><i>#u</i>, <i>#v</i>, <i>#pt</i>,
787<i>#km</i>, <i>#kh</i>, <i>#l</i></p>
788</ul> <p>These initial profiles have been either set by
789the user or
790have been calculated by a 1d-model prerun.<br> </p>In case
791of ASCII data output to local file PLOT1D_DATA,
792PALM additionally creates a NAMELIST parameter file (local name <a href="chapter_3.4.html#PLOT1D_PAR">PLOT1D_PAR</a>)
793which can be used as parameter input file for the plot software <a href="http://www.muk.uni-hannover.de/institut/software/profil_intro.html">profil</a>.
794Profiles can be directly plotted with <span style="font-weight: bold;">profil</span>
795using these two files. The
796plot layout is
797steered via the parameter input file. The values of these <span style="font-weight: bold;">profil</span>-parameters
798are determined by
799a set of PALM parameters (<a href="chapter_4.2.html#profile_columns">profile_columns</a>,
800<a href="chapter_4.2.html#profile_rows">profile_rows</a>,
801<a href="chapter_4.2.html#z_max_do1d">z_max_do1d</a>,
802<a href="chapter_4.2.html#cross_profiles">cross_profiles</a>,
803etc.) All parameter values can be changed by editing the parameter
804input
805file. <br><br>Further details about plotting vertical
806profiles with <span style="font-weight: bold;">profil </span>can
807be found in <a href="chapter_4.5.2.html">chapter
8084.5.2</a></td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="data_output_2d_on_each_pe"></a><b>data_output_2d_on</b>
809<br> <b>_each_pe</b></p> </td> <td style="vertical-align: top;">L<br> </td> <td style="vertical-align: top;"><span style="font-style: italic;">.T.</span><br> </td>
810<td style="vertical-align: top;">Output 2d cross section
811data by one or
812all processors.&nbsp; <p>In runs with several processors, by
813default, each processor
814outputs cross section data of its subdomain&nbsp;into an individual
815file. After PALM
816has finished, the contents of these files have to be sampled into one
817file<span style="font-weight: bold;"></span> using
818the program <tt>combine_plot_fields.x</tt>.&nbsp; </p>
819<p>Alternatively, by assigning <b>data_output_2d_on_each_pe</b>
820= <i>.F.,</i>
821the respective data is gathered on PE0 and output is done directly
822into one file, so <tt>combine_plot_fields.x</tt> does not
823have to be
824called. However, in case of very large numbers of horizontal
825gridpoints, sufficient
826memory is required on PE0. </p> </td> </tr>
827<tr> <td style="vertical-align: top;"> <p><a name="disturbance_amplitude"></a><b>disturbance<br>
828_amplitude</b></p> </td> <td style="vertical-align: top;">R</td> <td style="vertical-align: top;"><i>0.25</i></td>
829<td style="vertical-align: top;"> <p>Maximum
830perturbation amplitude of the random perturbations
831imposed to the horizontal velocity field (in m/s).&nbsp; </p>
832<p>The parameter <a href="#create_disturbances">create_disturbances</a>
833describes how to impose random perturbations to the horizontal velocity
834field. Since the perturbation procedure includes two filter operations,
835the amplitude assigned by <b>disturbance_amplitude</b> is
836only an
837approximate value of the real magnitude of the perturbation.</p> </td>
838</tr> <tr> <td style="vertical-align: top;"><p><a name="disturbance_energy_limit"></a><b>disturbance_energy</b>
839<br> <b>_limit</b></p> </td> <td style="vertical-align: top;">R</td> <td style="vertical-align: top;"><i>0.01</i></td>
840<td style="vertical-align: top;"> <p lang="en-GB">Upper
841limit value of the perturbation energy of
842the velocity field used as a criterion for imposing random
843perturbations (in m<sup>2</sup>/s<sup>2</sup>).&nbsp;
844</p> <p><span lang="en-GB"><font face="Thorndale, serif">The parameter </font></span><a href="#create_disturbances"><span lang="en-GB"><font face="Thorndale, serif">create_disturbances</font></span></a><font face="Thorndale, serif"><span lang="en-GB">
845describes how to impose
846random perturbations to the horizontal velocity field. The perturbation
847energy is defined as the volume average (over the total model domain)
848of the squares of the deviations of the velocity components from the
849mean flow (horizontal average). If the perturbation energy exceeds the
850assigned value, random perturbations to the fields of horizontal
851velocities are imposed no more. The value of this parameter usually
852must be determined by trial and error (it depends e.g. on the total
853number of grid points).</span> </font> </p> </td>
854</tr> <tr> <td style="vertical-align: top;"><p><a name="disturbance_level_b"></a><b>disturbance_level_b</b></p>
855</td> <td style="vertical-align: top;">R</td>
856<td style="vertical-align: top;"><i>zu(3)</i></td>
857<td style="vertical-align: top;"> <p lang="en-GB"><font face="Thorndale, serif"><font size="3">Lower
858limit of the vertical range for which random perturbations are to be
859imposed on the horizontal wind field (</font></font>in <font face="Thorndale, serif"><font size="3">m).&nbsp;
860</font></font> </p> <p><span lang="en-GB"><font face="Thorndale, serif">This
861parameter must hold the condition zu<i>(3)</i> &lt;= <b>disturbance_level_b</b>
862&lt;= <i>zu(</i></font></span><i><a href="chapter_4.1.html#nz"><span lang="en-GB"><font face="Thorndale, serif">nz-1</font></span></a><span lang="en-GB"><font face="Thorndale, serif">)</font></span></i><span lang="en-GB"><font face="Thorndale, serif">.
863Additionally, <b>disturbance_level_b</b>
864&lt;= </font></span><a href="#disturbance_level_t"><span lang="en-GB"><font face="Thorndale, serif">disturbance_level_t</font></span></a>
865<span lang="en-GB"><font face="Thorndale, serif">must
866also hold. <br> </font></span></p> <p><span lang="en-GB"><font face="Thorndale, serif">The
867parameter </font></span><a href="#create_disturbances"><span lang="en-GB"><font face="Thorndale, serif">create_disturbances</font></span></a><font face="Thorndale, serif"><span lang="en-GB">
868describes how to impose
869random perturbations to the horizontal velocity field</span></font><font face="Thorndale, serif"><span lang="en-GB">.</span>
870</font> </p> </td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="disturbance_level_t"></a><b>disturbance_level_t</b></p>
871</td> <td style="vertical-align: top;">R</td>
872<td style="vertical-align: top;"><i>zu(nz/3)</i></td>
873<td style="vertical-align: top;"> <p lang="en-GB"><font face="Thorndale, serif"><font size="3">Upper
874limit of the vertical range for which random perturbations are to be
875imposed on the horizontal wind field (</font></font>in <font face="Thorndale, serif"><font size="3">m).&nbsp;
876</font></font> </p> <p><span lang="en-GB"><font face="Thorndale, serif">This
877parameter must hold the condition <b>disturbance_level_t</b>
878&lt;= zu<i>(</i></font></span><i><a href="chapter_4.1.html#nz"><span lang="en-GB"><font face="Thorndale, serif">nz-1</font></span></a><span lang="en-GB"><font face="Thorndale, serif">)</font></span></i><span lang="en-GB"><font face="Thorndale, serif">.
879Additionally, </font></span><a href="#disturbance_level_b"><span lang="en-GB"><font face="Thorndale, serif">disturbance_level_b</font></span></a>
880<span lang="en-GB"><font face="Thorndale, serif">&lt;=
881<b>disturbance_level_t</b>
882must also hold.<br> </font></span></p> <p><span lang="en-GB"><font face="Thorndale, serif">The
883parameter </font></span><a href="#create_disturbances"><span lang="en-GB"><font face="Thorndale, serif">create_disturbances</font></span></a><font face="Thorndale, serif"><span lang="en-GB">
884describes how to impose
885random perturbations to the horizontal velocity field</span></font><font face="Thorndale, serif"><span lang="en-GB">.</span>
886</font> </p> </td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="do2d_at_begin"></a><b>do2d_at_begin</b></p>
887</td> <td style="vertical-align: top;">L<br> </td>
888<td style="vertical-align: top;">.F.<br> </td>
889<td style="vertical-align: top;"> <p>Output of 2d
890cross section data at the beginning of a run.&nbsp; </p> <p>The
891temporal intervals of output times of 2d cross section data (see <a href="chapter_4.2.html#data_output">data_output</a>)
892are usually determined with parameters <a href="chapter_4.2.html#dt_do2d_xy">dt_do2d_xy</a>, <a href="chapter_4.2.html#dt_do2d_xz">dt_do2d_xz</a>
893and <a href="chapter_4.2.html#dt_do2d_yz">dt_do2d_yz</a>.
894By assigning <b>do2d_at_begin</b> = <i>.T.</i>
895an additional output
896will be made at the
897beginning of a run (thus at the time t = 0 or at the respective
898starting times of restart runs).</p> </td> </tr> <tr>
899<td style="vertical-align: top;"> <p><a name="do3d_at_begin"></a><b>do3d_at_begin</b></p>
900</td> <td style="vertical-align: top;">L<br> </td>
901<td style="vertical-align: top;">.F.<br> </td>
902<td style="vertical-align: top;">Output of 3d volume data
903at the beginning
904of a run.<br><br>The temporal intervals of output times of
9053d volume data (see <a href="chapter_4.2.html#data_output">data_output</a>)
906is usually determined with parameter <a href="chapter_4.2.html#dt_do3d">dt_do3d</a>.
907By assigning <b>do3d_at_begin</b> = <i>.T.</i>
908an additional output
909will be made at the
910beginning of a run (thus at the time t = 0 or at the respective
911starting times of restart runs).</td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="do3d_compress"></a><b>do3d_compress</b></p>
912</td> <td style="vertical-align: top;">L<br> </td>
913<td style="vertical-align: top;">.F.<br> </td>
914<td style="vertical-align: top;"> <p>Output of data
915for 3d plots in compressed form.&nbsp; </p> <p>This
916parameter only applies for &nbsp;<a href="chapter_4.2.html#data_output_format">data_output_format</a>
917= <span style="font-style: italic;">'avs'</span>.</p><p>Output
918of 3d volume data may need huge amounts of disc storage
919(up to several Terabytes ore more). Data compression can serve to
920reduce this requirement. PALM is able to output 3d data in compressed
921form using 32-bit integers, if <span style="font-weight: bold;">do3d_compress</span>
922= <span style="font-style: italic;">.T.</span> is
923assigned. This
924yields a loss of accuracy, but the file size is clearly reduced. The
925parameter <a href="chapter_4.2.html#do3d_precision">do3d_precision</a>
926can be used to separately define the number of significant digits for
927each quantity.<br> </p> <p>So far compressed data
928output is only possible for Cray-T3E
929machines. Additional information for
930handling compressed data is given in <a href="chapter_4.5.6.html">chapter
9314.5.6</a>.</p> </td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="do3d_precision"></a><b>do3d_precision</b></p>
932</td> <td style="vertical-align: top;">C *
9337&nbsp; <br>
934&nbsp; (100)</td> <td style="vertical-align: top;">see
935right<br> </td> <td style="vertical-align: top;">
936<p>Significant digits in case of compressed data
937output.&nbsp; </p> <p>This parameter only applies for
938&nbsp;<a href="chapter_4.2.html#data_output_format">data_output_format</a>
939= <span style="font-style: italic;">'avs'</span>.</p><p>In
940case that data compression is used for output of 3d data
941(see <a href="chapter_4.2.html#do3d_compress">do3d_compress</a>),
942this parameter determines the number of significant digits
943which are to be output.<br> </p> <p>Fewer digits
944clearly reduce the amount
945of data. Assignments have to be given separately for each individual
946quantity via a character string of the form <span style="font-style: italic;">'&lt;quantity
947name&gt;&lt;number of
948significant digits&gt;'</span>, e.g. <span style="font-style: italic;">'pt2'</span>.
949Only those quantities listed in <a href="chapter_4.2.html#data_output">data_output</a>
950are admitted. Up to 9 significant digits are allowed (but large values
951are not very reasonable
952because they do not effect a significant compression).<br> </p>
953<p>The default assignment is <span style="font-weight: bold;">do3d_precision</span>
954= <span style="font-style: italic;">'u2'</span>, <span style="font-style: italic;">'v2'</span>, <span style="font-style: italic;">'w2'</span>, <span style="font-style: italic;">'p5'</span>, <span style="font-style: italic;">'pt2'</span>.</p> </td>
955</tr><tr> <td style="vertical-align: top;"> <p><a name="dt_laufparameter"></a><b>dt</b></p>
956</td> <td style="vertical-align: top;">R</td>
957<td style="vertical-align: top;"><i>variable</i></td>
958<td style="vertical-align: top;"> <p lang="en-GB"><font face="Thorndale, serif"><font size="3">Time
959step to be used by the 3d-model (</font></font>in <font face="Thorndale, serif"><font size="3">s).&nbsp;
960</font></font> </p> <p><span lang="en-GB"><font face="Thorndale, serif">This parameter</font></span>
961<font face="Thorndale, serif"><span lang="en-GB">is
962described in
963detail with the initialization parameters (see</span></font><span lang="en-GB"><font face="Thorndale, serif"> </font></span><a href="chapter_4.1.html#dt"><span lang="en-GB"><font face="Thorndale, serif">dt</font></span></a><font face="Thorndale, serif"><span lang="en-GB">).
964Additionally, it may be
965used as a run parameter and then applies to all restart runs (until it
966is changed again). A switch from a constant time step to a variable
967time step can be achieved with <b>dt</b> = <i>-1.0</i>.</span>
968</font> </p> </td> </tr> <tr> <td style="vertical-align: top;"><a name="dt_averaging_input"></a><span style="font-weight: bold;">dt_averaging_input</span><br>
969</td> <td style="vertical-align: top;">R<br> </td>
970<td style="vertical-align: top;"><span style="font-style: italic;">0.0</span><br> </td>
971<td style="vertical-align: top;">Temporal interval
972of&nbsp;data which are subject to temporal averaging (in s).<br><br>By
973default, data from each timestep within the interval defined by <a href="chapter_4.2.html#averaging_interval">averaging_interval</a>
974are used for calculating the temporal average. By choosing <span style="font-weight: bold;">dt_averaging_input</span>
975&gt; <span lang="en-GB"><font face="Thorndale, serif"> </font></span><a href="chapter_4.1.html#dt"><span lang="en-GB"><font face="Thorndale, serif">dt</font></span></a><font face="Thorndale, serif"><span lang="en-GB"></span></font><span lang="en-GB"></span><span style="font-style: italic;"></span>,
976the number of time levels entering the average can be minimized. This
977reduces the CPU-time of a run but may worsen the quality of the
978average's statistics.<br><br><font face="Thorndale, serif"><span lang="en-GB">With
979variable time step (see <span style="font-weight: bold;">dt</span>),
980the number of time levels entering the average can vary from one
981averaging interval to the next (for a more detailed explanation see </span></font><font><a href="#averaging_interval"><span lang="en-GB"><font face="Thorndale, serif">averaging_interval</font></span></a>)</font><font face="Thorndale, serif"><span lang="en-GB">. It
982is approximately given by the quotient of <span style="font-weight: bold;">averaging_interval</span> /
983MAX(<span style="font-weight: bold;"> dt_averaging_input</span>,
984<span style="font-weight: bold;">dt</span>) (which
985gives a more or less exact value if a fixed timestep is used and if
986this is an integral divisor of <span style="font-weight: bold;">dt_averaging_input</span>).</span></font>&nbsp;
987<br><br><span style="font-weight: bold;">Example:</span><br>With
988an averaging interval of 100.0 s and <span style="font-weight: bold;">dt_averaging_input</span> =
989<span style="font-style: italic;">10.0</span>,
990the time levels entering the average have a (minimum) distance of 10.0
991s (their distance may of course be larger if the current timestep is
992larger than 10.0 s), so the average is calculated from the data of
993(maximum) 10 time levels.<br><br><font face="Thorndale, serif"><span lang="en-GB">It
994is allowed
995to change <b>dt_averaging_input</b> during a job chain. If
996the last averaging
997interval of the run previous to the change could not be completed (i.e.
998has to be finished in the current run), the individual profiles and/or
999spectra entering the averaging are not uniformly distributed over the
1000averaging interval.<br><br></span></font>Parameter&nbsp;<a href="#dt_averaging_input_pr">dt_averaging_input_pr</a>&nbsp;can
1001be used to define&nbsp;a different temporal interval&nbsp;for
1002vertical profile data and spectra.<br> </td> </tr>
1003<tr> <td style="vertical-align: top;"> <p><a name="dt_averaging_input_pr"></a><b>dt_averaging_input_pr</b></p>
1004</td> <td style="vertical-align: top;">R</td>
1005<td style="vertical-align: top;"><span style="font-style: italic;">value of <a href="#dt_averaging_input">dt_<br>averaging_<br>input</a></span></td>
1006<td style="vertical-align: top;"> <p lang="en-GB">Temporal
1007interval of&nbsp;data which are subject to temporal averaging of <font face="Thorndale, serif"><font size="3">vertical
1008profiles and/or spectra&nbsp;(</font></font>in <font face="Thorndale, serif"><font size="3">s).&nbsp;
1009</font></font> </p> <p>By default, data from
1010each timestep within the interval defined by<font face="Thorndale, serif"><span lang="en-GB"> </span></font><a href="#averaging_interval_pr"><span lang="en-GB"><font face="Thorndale, serif">averaging_interval_pr</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><span lang="en-GB"><font face="Thorndale, serif">and </font></span><a href="#averaging_interval_sp"><span lang="en-GB"><font face="Thorndale, serif">averaging_interval_sp</font></span></a><span lang="en-GB"><font face="Thorndale, serif"> </font></span>are
1011used for calculating the temporal average.&nbsp;By choosing <span style="font-weight: bold;">dt_averaging_input_pr</span>
1012&gt; <span lang="en-GB"><font face="Thorndale, serif"> </font></span><a href="chapter_4.1.html#dt"><span lang="en-GB"><font face="Thorndale, serif">dt</font></span></a><font face="Thorndale, serif"><span lang="en-GB"></span></font><span lang="en-GB"></span><span style="font-style: italic;"></span>,
1013the number of time levels entering the average can be minimized. This
1014reduces the CPU-time of a run but may worsen the quality of the
1015average's statistics. <span lang="en-GB"><font face="Thorndale, serif"><span style="font-weight: bold;"></span><span style="font-weight: bold;"></span></font></span><a href="chapter_4.1.html#dt"><span lang="en-GB"></span></a><font face="Thorndale, serif"><span lang="en-GB"></span></font><span lang="en-GB"></span><br> </p><p>For
1016more explanations see parameter <a href="#dt_averaging_input">dt_averaging_input</a>.<a href="chapter_4.1.html#dt"><span lang="en-GB"></span></a><font face="Thorndale, serif"><span lang="en-GB"></span></font></p></td>
1017</tr> <tr> <td style="vertical-align: top;"><a name="dt_data_output"></a><span style="font-weight: bold;">dt_data_output</span><br>
1018</td> <td style="vertical-align: top;">R<br> </td>
1019<td style="vertical-align: top;"><span style="font-style: italic;">9999999.9</span><br>
1020</td> <td style="vertical-align: top;"><p lang="en-GB"><font face="Thorndale"><font face="Thorndale, serif">Temporal interval</font>
1021at which&nbsp;data (3d volume data (instantaneous or time
1022averaged),
1023cross sections (instantaneous or time averaged), vertical profiles,
1024spectra) shall be output (</font>in <font face="Thorndale">s).&nbsp;</font></p>
1025<span lang="en-GB"><font face="Thorndale">If
1026data output&nbsp;is switched on (see </font></span><a href="chapter_4.2.html#data_output"><span lang="en-GB"><font face="Thorndale">data_output</font></span></a><span lang="en-GB"><font face="Thorndale">, <a href="#data_output_pr">data_output_pr</a>, <a href="#data_output_sp">data_output_sp</a>, and </font></span><a href="chapter_4.2.html#section_xy"><span lang="en-GB"><font face="Thorndale">section_xy</font></span></a><span lang="en-GB"><font face="Thorndale">), this
1027parameter can be used to
1028assign the temporal interval at which these data shall be
1029output. </font></span><span lang="en-GB"><font face="Thorndale">Output can be skipped at the beginning of a
1030simulation using parameter <a href="#skip_time_data_output">skip_time_data_output</a>,
1031which has zero value by default. </font></span><span lang="en-GB"><font face="Thorndale">Reference
1032time is the beginning of the simulation, i.e. output
1033takes place at times t = <b>skip_time_data_output +
1034dt_data_output</b>, <span style="font-weight: bold;">skip_time_data_output</span>
1035+ 2*<b>dt_data_output</b>, <span style="font-weight: bold;">skip_time_data_output</span>
1036+ 3*<b>dt_data_output</b>,
1037etc. Since output is only done at the discrete time levels given by
1038the&nbsp;timestep used, the actual output times can slightly
1039deviate
1040from these theoretical values</font></span><a href="chapter_4.2.html#dt_dopr_zeitpunkte"><span lang="en-GB"></span></a><span lang="en-GB"><font face="Thorndale">.<br><br>Individual temporal
1041intervals for the different output quantities can be assigned using
1042parameters <a href="#dt_do3d">dt_do3d</a>, <a href="#dt_do2d_xy">dt_do2d_xy</a>, <a href="dt_do2d_xz">dt_do2d_xz</a>, <a href="#dt_do2d_yz">dt_do2d_yz</a>, <a href="#dt_dopr">dt_dopr</a>, <a href="#dt_dosp">dt_dosp</a>,
1043and <a href="#dt_data_output_av">dt_data_output_av</a>.</font></span>
1044</td> </tr> <tr> <td style="vertical-align: top;"><a name="dt_data_output_av"></a><span style="font-weight: bold;">dt_data_output_av</span><br>
1045</td> <td style="vertical-align: top;">R<br> </td>
1046<td style="vertical-align: top;"><i>value of
1047&nbsp;<a href="chapter_4.2.html#dt_data_output">dt_data_<br>output</a></i>
1048</td> <td style="vertical-align: top;"><p lang="en-GB"><font face="Thorndale"><font face="Thorndale, serif">Temporal interval</font>
1049at which time averaged 3d volume data and/or 2d cross section data
1050shall be output (</font>in <font face="Thorndale">s).&nbsp;</font></p><span lang="en-GB"><font face="Thorndale">If data
1051output of time averaged 2d and 3d data is switched on (see </font></span><a href="chapter_4.2.html#data_output"><span lang="en-GB"><font face="Thorndale">data_output</font></span></a>&nbsp;<span lang="en-GB"><font face="Thorndale">and </font></span><a href="chapter_4.2.html#section_xy"><span lang="en-GB"><font face="Thorndale">section_xy</font></span></a><span lang="en-GB"><font face="Thorndale">), this
1052parameter can be used to
1053assign the temporal interval at which they shall be
1054output. </font></span><span lang="en-GB"><font face="Thorndale">Output can be skipped at the beginning of a
1055simulation using parameter <a href="#skip_time_data_output_av">skip_time_data_output_av</a>,
1056which has zero value by default. </font></span><span lang="en-GB"><font face="Thorndale">Reference
1057time is the beginning of the simulation, i.e. output
1058takes place at times t = <b>skip_time_data_output_av +
1059dt_data_output_av</b>, <span style="font-weight: bold;">skip_time_data_output_av</span>
1060+ 2*<b>dt_data_output_av</b>, <span style="font-weight: bold;">skip_time_data_output_av</span>
1061+ 3*<b>dt_data_output_av</b>,
1062etc. Since output is only done at the discrete time levels given by
1063the&nbsp;timestep used, the actual output times can slightly
1064deviate from
1065these theoretical values</font></span><a href="chapter_4.2.html#dt_dopr_zeitpunkte"><span lang="en-GB"></span></a><span lang="en-GB"><font face="Thorndale">.<br><br></font></span>The
1066length of the averaging interval is controlled via parameter <a href="chapter_4.2.html#averaging_interval">averaging_interval</a>.</td>
1067</tr><tr> <td style="vertical-align: top;"> <p><a name="dt_disturb"></a><b>dt_disturb</b></p>
1068</td> <td style="vertical-align: top;">R</td>
1069<td style="vertical-align: top;"><i>9999999.9</i></td>
1070<td style="vertical-align: top;"> <p lang="en-GB"><font face="Thorndale"><font face="Thorndale, serif">Temporal
1071interval</font> at which random
1072perturbations are to be imposed on the horizontal velocity field
1073(</font>in <font face="Thorndale">s).&nbsp; </font>
1074</p> <p><span lang="en-GB"><font face="Thorndale, serif">The parameter </font></span><a href="#create_disturbances"><span lang="en-GB"><font face="Thorndale, serif">create_disturbances</font></span></a><font face="Thorndale, serif"><span lang="en-GB">
1075describes how to impose
1076random perturbations to the horizontal velocity field</span></font><font face="Thorndale, serif"><span lang="en-GB">.</span>
1077</font> </p> </td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="dt_dopr"></a><b>dt_dopr</b></p>
1078</td> <td style="vertical-align: top;">R</td>
1079<td style="vertical-align: top;"><i>value of
1080&nbsp;<a href="#dt_data_output">dt_data_<br>output</a></i></td>
1081<td style="vertical-align: top;"> <p><span lang="en-GB"><font face="Thorndale">Temporal
1082interval at
1083which data&nbsp;of vertical profiles shall be output (to local
1084file <a href="chapter_3.4.html#DATA_1D_PR_NETCDF">DATA_1D_PR_NETCDF</a>
1085or/and </font></span><a href="chapter_3.4.html#PLOT1D_DATA"><span lang="en-GB"><font face="Thorndale">PLOT1D_DATA</font></span></a><span lang="en-GB"><font face="Thorndale">) (</font></span>in
1086<span lang="en-GB"><font face="Thorndale">s).&nbsp;
1087</font></span> </p> <p><span lang="en-GB"><font face="Thorndale">If output of
1088horizontally averaged vertical profiles is switched on (see </font></span><a href="chapter_4.2.html#data_output_pr"><span lang="en-GB"><font face="Thorndale">data_output_pr</font></span></a><span lang="en-GB"><font face="Thorndale">), </font></span><span lang="en-GB"><font face="Thorndale">this
1089parameter can be used to
1090assign the temporal interval at which profile data shall be output.</font></span><span lang="en-GB"><font face="Thorndale"> </font></span><span lang="en-GB"><font face="Thorndale">Output can
1091be skipped at the beginning of a simulation using parameter <a href="#skip_time_dopr">skip_time_dopr</a>, which has
1092zero value by default. </font></span><span lang="en-GB"></span><span lang="en-GB"><font face="Thorndale">Reference
1093time is the beginning
1094of the simulation, thus t = 0,&nbsp;</font></span><span lang="en-GB"><font face="Thorndale">i.e. output
1095takes place at times t = <b>skip_time_dopr + dt_dopr</b>, <span style="font-weight: bold;">skip_time_dopr</span> + 2*<b>dt_dopr</b>,
1096<span style="font-weight: bold;">skip_time_dopr</span>
1097+ 3*<b>dt_dopr</b>,
1098etc.</font></span><span lang="en-GB"><font face="Thorndale"> Since
1099profiles can not be calculated for times lying within a time step
1100interval, the output times can deviate from these theoretical values.
1101If a time step ranges from t = 1799.8 to t = 1800.2, then in the
1102example above the output would take place at t = 1800.2. In general,
1103the output always lie between t = 1800.0 and t = 1800.0 + </font></span><a href="chapter_4.1.html#dt"><span lang="en-GB"><font face="Thorndale">dt</font></span></a><span lang="en-GB"><font face="Thorndale">. If the
1104model uses a variable time step, these
1105deviations from the theoretical output times will of course be
1106different for each output time.<br> </font></span></p>
1107<p><span lang="en-GB"><font face="Thorndale">In
1108order to
1109guarantee an output of profile data at the end of a simulation (see </font></span><font><a href="chapter_4.1.html#end_time"><span lang="en-GB"><font face="Thorndale">end_time</font></span></a></font><span lang="en-GB"><font face="Thorndale">) in any way</font></span><span lang="en-GB"><font face="Thorndale">,&nbsp;
1110<span style="font-weight: bold;">end_time</span>
1111should be equal or a little bit
1112larger than the respective theoretical output time. For example, if <b>dt_dopr</b>
1113= <i>900.0</i><span style="font-style: italic;">
1114</span>and 3600.0
1115seconds are to be simulated, then <b>end_time</b>
1116&gt;= 3600.0 should be chosen.</font></span><a href="chapter_4.1.html#dt"><span lang="en-GB"></span></a><span lang="en-GB"><font face="Thorndale"><span style="font-weight: bold;"></span>&nbsp; </font></span>
1117</p> <p><span lang="en-GB"><font face="Thorndale">A selection of
1118profiles to be output can be done via parameter </font></span><a href="chapter_4.2.html#data_output_pr"><span lang="en-GB"><font face="Thorndale">data_output_pr</font></span></a><span lang="en-GB"><font face="Thorndale">.&nbsp;</font></span>
1119</p> </td> </tr> <tr> <td style="vertical-align: top;"><a name="dt_dopr_listing"></a><span style="font-weight: bold;">dt_dopr_listing</span><br>
1120</td> <td style="vertical-align: top;">R<br> </td>
1121<td style="vertical-align: top;"><i>9999999.9</i></td>
1122<td style="vertical-align: top;"> <p><span lang="en-GB"><font face="Thorndale, serif">Temporal
1123interval</font> at which data <font face="Thorndale">of
1124vertical
1125profiles shall be output (output for printouts, local file </font></span><a href="chapter_3.4.html#LIST_PROFIL"><span lang="en-GB"><font face="Thorndale">LIST_PROFIL</font></span></a><span lang="en-GB"><font face="Thorndale">) (</font></span>in
1126<span lang="en-GB"><font face="Thorndale">s).&nbsp;</font></span>
1127</p> <p>T<span lang="en-GB"></span><a href="chapter_4.2.html#pr1d"><span lang="en-GB"></span></a><span lang="en-GB"></span><span lang="en-GB"><font face="Thorndale">his
1128parameter can be used to
1129assign the temporal interval at which profile data shall be output.</font></span><span lang="en-GB"><font face="Thorndale"> Reference
1130time is the beginning
1131of the simulation, thus t = 0. For example if <b>dt_dopr_listing</b>
1132= 1800.0,
1133then output takes place at t = 1800.0, 3600.0, 5400.0, etc. Since
1134profiles can not be calculated for times lying within a time step
1135interval, the output times can deviate from these theoretical values.
1136If a time step ranges from t = 1799.8 to t = 1800.2, then in the
1137example above the output would take place at t = 1800.2. In general,
1138the output always lie between t = 1800.0 and t = 1800.0 + </font></span><a href="chapter_4.1.html#dt"><span lang="en-GB"><font face="Thorndale">dt</font></span></a> <span lang="en-GB"><font face="Thorndale">(numbers
1139are related to
1140the
1141example above). If the model uses a variable time step, these
1142deviations from the theoretical output times will of course be
1143different for each output time.<br> </font></span></p>
1144<p><span lang="en-GB"><font face="Thorndale">In
1145order to
1146guarantee an output of profile data at the end of a simulation (see </font></span><font><a href="chapter_4.1.html#end_time"><span lang="en-GB"><font face="Thorndale">end_time</font></span></a></font><span lang="en-GB"><font face="Thorndale">) in any way</font></span><span lang="en-GB"><font face="Thorndale">,&nbsp;
1147<span style="font-weight: bold;">end_time</span>
1148should be a little bit
1149larger than the respective theoretical output time. For example, if <b>dt_dopr_listing</b>
1150= <i>900.0</i><span style="font-style: italic;">
1151</span>and 3600.0
1152seconds are to be simulated, then it should be at least&nbsp; <b>end_time</b>
1153&gt; 3600.0 + </font></span><a href="chapter_4.1.html#dt"><span lang="en-GB"><font face="Thorndale">dt</font></span></a><span lang="en-GB"><font face="Thorndale">. If
1154variable time steps are used
1155(which is the default), <span style="font-weight: bold;">dt</span>
1156should be properly estimated.&nbsp; </font></span> </p>
1157<p><span lang="en-GB"><font face="Thorndale">Data
1158and output
1159format of the file </font></span><a href="chapter_3.4.html#LIST_PROFIL"><span lang="en-GB"><font face="Thorndale">LIST_PROFIL</font></span></a>
1160<span lang="en-GB"><font face="Thorndale">is
1161internally fixed. In this file
1162the profiles of the most important model variables are arranged in
1163adjacent columns.</font></span> </p> </td> </tr>
1164<tr> <td style="vertical-align: top;"> <p><a name="dt_dots"></a><b>dt_dots</b></p>
1165</td> <td style="vertical-align: top;">R</td>
1166<td style="vertical-align: top;"><span style="font-style: italic;">see right</span></td>
1167<td style="vertical-align: top;"> <p lang="en-GB"><font face="Thorndale"><font face="Thorndale, serif">Temporal
1168interval</font> at which&nbsp;time series data shall be
1169output (</font>in <font face="Thorndale">s).&nbsp;</font>
1170</p> <p>The default interval for the output of timeseries
1171is calculated as shown below (this tries to minimize the number of
1172calls of <span style="font-family: Courier New,Courier,monospace;">flow_statistics</span>)</p><p style="font-family: Courier New,Courier,monospace;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
1173IF ( <a href="#averaging_interval_pr">averaging_interval_pr</a>
1174== 0.0 )&nbsp; THEN<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
1175<span style="font-weight: bold;">dt_dots</span> =
1176MIN( <a href="#dt_run_control">dt_run_control</a>, <a href="#dt_dopr">dt_dopr</a> )<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
1177ELSE<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
1178<span style="font-weight: bold;">dt_dots</span> =
1179MIN( dt_run_control, <a href="#dt_averaging_input_pr">dt_averaging_input_pr</a>
1180)<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
1181ENDIF</p><p>This parameter can be used to
1182assign the temporal interval at which data points shall be output. <span lang="en-GB"><font face="Thorndale">Reference
1183time is the beginning of
1184&nbsp;the simulation, i.e. output takes place at times t = <b>dt_dots</b>,
11852*<b>dt_dots</b>, 3*<b>dt_dots</b>, etc. The
1186actual output times can
1187deviate from these theoretical values (see </font></span><a href="#dt_dopr_zeitpunkte"><span lang="en-GB"><font face="Thorndale">dt_dopr</font></span></a><span lang="en-GB"><font face="Thorndale">).&nbsp;
1188Is <b>dt_dots</b> &lt; </font></span><a href="chapter_4.1.html#dt"><span lang="en-GB"><font face="Thorndale">dt</font></span></a><span lang="en-GB"><font face="Thorndale">, then data
1189of the time series are
1190written after each time step (if this is requested it should be <b>dt_dots</b>
1191= <i>0</i>).</font></span></p><p><span lang="en-GB"><font face="Thorndale">The default
1192value of <span style="font-weight: bold;">dt_dots</span>
1193is calculated as follows:</font></span></p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
1194IF ( <a href="#averaging_interval_pr">averaging_interval_pr</a>
1195== 0.0 )&nbsp; THEN<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
1196<span style="font-weight: bold;">dt_dots</span> =
1197MIN( <a href="#dt_run_control">dt_run_control</a>, <a href="#dt_dopr">dt_dopr</a> )<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
1198ELSE<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
1199<span style="font-weight: bold;">dt_dots</span> =
1200MIN( <span style="font-weight: bold;">dt_run_control</span>,
1201<a href="#dt_averaging_input_pr">dt_averaging_input_pr</a>
1202)<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
1203ENDIF<br><br>(which minimizes the number of calls of
1204routine flow_statistics).<br><p>By default time series data
1205is output to the local file <a href="chapter_3.4.html#DATA_1D_TS_NETCDF">DATA_1D_TS_NETCDF</a>.
1206Because of the default settings of <span style="font-weight: bold;">dt_dots</span>,
1207it will&nbsp;generally be created for each model run. The file's
1208format is NetCDF.&nbsp; Further details about processing NetCDF
1209data are given in chapter <a href="chapter_4.5.1.html">4.5.1</a>.</p>The
1210file contains the following timeseries quantities (the first column
1211gives the name of the quantities as used in the NetCDF file):<br><table style="text-align: left; width: 100%;" cellpadding="2" cellspacing="2"> <tbody> <tr> <td style="font-style: italic; vertical-align: middle;">E<br>
1212</td> <td style="vertical-align: top;">Total
1213kinetic energy of
1214the flow (in m<sup>2</sup>/s<sup>2</sup>)
1215(normalized with respect to the total number of grid points).</td>
1216</tr> <tr> <td style="font-style: italic; vertical-align: middle;">E*<br>
1217</td> <td style="vertical-align: top;">Perturbation
1218kinetic
1219energy of the flow (in m<sup>2</sup>/s<sup>2</sup>)<sup>
1220</sup>(normalized
1221with respect to the total number of grid
1222points)</td> </tr> <tr> <td style="vertical-align: top; font-style: italic;">dt<br>
1223</td> <td style="vertical-align: top;">Time step
1224size (in s).</td> </tr> <tr> <td style="vertical-align: top; font-style: italic;">u<sub>*</sub></td>
1225<td style="vertical-align: top;">Friction velocity (in
1226m/s)
1227(horizontal average).</td> </tr> <tr> <td style="vertical-align: top; font-style: italic;">w<sub>*</sub></td>
1228<td style="vertical-align: top;">Vertical velocity scale
1229of
1230the CBL (in m/s) (horizontal average)</td> </tr> <tr>
1231<td style="vertical-align: top; font-style: italic;">th<sub>*</sub></td>
1232<td style="vertical-align: top;">Temperature
1233scale (Prandtl layer), defined as <i>w"pt"0
1234/&nbsp;</i><i>u<sub>*</sub></i>
1235(horizontal
1236average) (in K).</td> </tr> <tr> <td style="vertical-align: top; font-style: italic;">umax<br>
1237</td> <td style="vertical-align: top;">Maximum
1238u-component of the
1239velocity (in m/s).</td> </tr> <tr> <td style="vertical-align: top; font-style: italic;">vmax<br>
1240</td> <td style="vertical-align: top;">Maximum
1241v-component of the
1242velocity (in m/s).</td> </tr> <tr> <td style="vertical-align: top; font-style: italic;">wmax<br>
1243</td> <td style="vertical-align: top;">Maximum
1244w-component of the
1245velocity (in m/s).</td> </tr> <tr> <td style="vertical-align: top; font-style: italic;">div_old<br>
1246</td> <td style="vertical-align: top;">Divergence
1247of the velocity
1248field before the pressure
1249solver has been called (normalized with respect to the total number of
1250grid points) (in 1/s).</td> </tr> <tr> <td style="vertical-align: top; font-style: italic;">div_new</td>
1251<td style="vertical-align: top;">Divergence of the
1252velocity
1253field after the pressure
1254solver has been called (normalized with respect to the total number of
1255grid points) (in 1/s).</td> </tr> <tr> <td style="vertical-align: top; font-style: italic;">z_i_wpt</td>
1256<td style="vertical-align: top;">Height of the convective
1257boundary layer (horizontal average)
1258determined by the height of the minimum sensible heat flux (in m).</td>
1259</tr> <tr> <td style="vertical-align: top; font-style: italic;">z_i_pt</td>
1260<td style="vertical-align: top;">Height of the convective
1261boundary layer (horizontal average)
1262determined by the temperature profile (in m).</td> </tr> <tr>
1263<td style="vertical-align: top; font-style: italic;">w"pt"0</td>
1264<td style="vertical-align: top;">Subgrid-scale sensible
1265heat flux near the surface (horizontal
1266average)
1267between z = 0 and z = z<sub>p</sub> = zu(1) (there it
1268corresponds to
1269the total heat flux) (in K m/s).</td> </tr> <tr> <td style="vertical-align: top; font-style: italic;">w"pt"</td>
1270<td style="vertical-align: top;">Subgrid-scale heat flux
1271(horizontal average) for z = zw(1) (in K
1272m/s).</td> </tr> <tr> <td style="vertical-align: top; font-style: italic;">wpt</td>
1273<td style="vertical-align: top;">Total heat flux
1274(horizontal average) for z = zw(1) (in K m/s).</td> </tr> <tr>
1275<td style="vertical-align: top; font-style: italic;">pt(0)</td>
1276<td style="vertical-align: top;">Potential temperature at
1277the surface (horizontal average) (in K).</td> </tr> <tr>
1278<td style="vertical-align: top; font-style: italic;">pt(zp)</td>
1279<td style="vertical-align: top;">Potential temperature for
1280z = zu(1) (horizontal average) (in K).</td> </tr> <tr>
1281<td style="vertical-align: top; font-style: italic;">splptx</td>
1282<td style="vertical-align: top;">Percentage of grid points
1283using upstream scheme along x with
1284upstream-spline advection switched on.</td> </tr> <tr>
1285<td style="vertical-align: top; font-style: italic;">splpty</td>
1286<td style="vertical-align: top;">Percentage of grid points
1287using upstream scheme along y with
1288upstream-spline
1289advection switched on.</td> </tr> <tr> <td style="vertical-align: top; font-style: italic;">splptz</td>
1290<td style="vertical-align: top;">Percentage of grid points
1291using upstream scheme along z with
1292upstream-spline
1293advection switched on.<br> </td> </tr> <tr> <td style="vertical-align: top; font-style: italic;">L</td>
1294<td style="vertical-align: top;">Monin-Obukhov length.</td>
1295</tr> </tbody> </table><br>Additionally, the
1296user can add his own timeseries quantities to the file, by using the
1297user-interface subroutines<span style="font-family: Courier New,Courier,monospace;"> <a href="chapter_3.5.1.html#user_init">user_init</a> </span>and<span style="font-family: Courier New,Courier,monospace;"> <a href="chapter_3.5.1.html#user_statistics">user_statistics</a></span>.
1298These routines contain (as comment lines) a simple example how to do
1299this.<br><br>Time series data refers to the total
1300domain, but time series for subdomains can also be output (see <a href="chapter_4.1.html#statistic_regions">statistic_regions</a>).
1301However, the following time series always present the values of the
1302total model domain (even with output for subdomains): <i>umax</i>,
1303<i>vmax</i>, <i>wmax</i>, <i>div_old</i>,
1304<i>div_new</i>.</td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="dt_do2d_xy"></a><b>dt_do2d_xy</b></p>
1305</td> <td style="vertical-align: top;">R</td>
1306<td style="vertical-align: top;"><i>value of
1307&nbsp;<a href="chapter_4.2.html#dt_data_output">dt_data_<br>output</a></i></td>
1308<td style="vertical-align: top;"> <p lang="en-GB"><font face="Thorndale"><font face="Thorndale, serif">Temporal
1309interval</font> at which&nbsp;horizontal cross section data
1310shall be output (</font>in <font face="Thorndale">s).&nbsp;
1311</font> </p> <p><span lang="en-GB"><font face="Thorndale">If output of
1312horizontal cross sections is switched on (see </font></span><a href="#data_output"><span lang="en-GB"><font face="Thorndale">data_output</font></span></a>
1313<span lang="en-GB"><font face="Thorndale">and
1314</font></span><a href="#section_xy"><span lang="en-GB"><font face="Thorndale">section_xy</font></span></a><span lang="en-GB"><font face="Thorndale">), this
1315parameter can be used to
1316assign the temporal interval at which cross section data shall be
1317output. </font></span><span lang="en-GB"><font face="Thorndale">Output can be skipped at the beginning of a
1318simulation using parameter <a href="#skip_time_do2d_xy">skip_time_do2d_xy</a>,
1319which has zero value by default. </font></span><span lang="en-GB"><font face="Thorndale">Reference
1320time is the beginning of the simulation, i.e. output
1321takes place at times t = <b>skip_time_do2d_xy + dt_do2d_xy</b>,
1322<span style="font-weight: bold;">skip_time_do2d_xy</span>
1323+ 2*<b>dt_do2d_xy</b>, <span style="font-weight: bold;">skip_time_do2d_xy</span>
1324+ 3*<b>dt_do2d_xy</b>,
1325etc. The actual output times can deviate from these theoretical values
1326(see </font></span><a href="#dt_dopr_zeitpunkte"><span lang="en-GB"><font face="Thorndale">dt_dopr</font></span></a><span lang="en-GB"><font face="Thorndale">).<br>
1327</font></span></p> <p><span lang="en-GB"><font face="Thorndale">Parameter </font></span><a href="#do2d_at_begin"><span lang="en-GB"><font face="Thorndale">do2d_at_begin</font></span></a>
1328has to be used if an additional output is wanted at the start of a run <span lang="en-GB"><font face="Thorndale">(thus at
1329the time t = 0 or at the
1330respective starting times of restart runs).</font></span> </p>
1331</td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="dt_do2d_xz"></a><b>dt_do2d_xz</b></p>
1332</td> <td style="vertical-align: top;">R</td>
1333<td style="vertical-align: top;"><i>value of
1334&nbsp;<a href="chapter_4.2.html#dt_data_output">dt_data_<br>output</a></i></td>
1335<td style="vertical-align: top;"> <p lang="en-GB"><font face="Thorndale"><font face="Thorndale, serif">Temporal
1336interval</font> at which&nbsp;vertical cross sections data
1337(xz) shall be output (</font>in <font face="Thorndale">s).&nbsp;
1338</font> </p> <p><span lang="en-GB"><font face="Thorndale">If output of
1339horizontal cross sections is switched on (see </font></span><a href="#data_output"><span lang="en-GB"><font face="Thorndale">data_output</font></span></a>
1340<span lang="en-GB"><font face="Thorndale">and
1341</font></span><a href="#section_xz"><span lang="en-GB"><font face="Thorndale">section_xz</font></span></a><span lang="en-GB"><font face="Thorndale">),
1342this parameter can be used to assign the temporal interval at which
1343cross section data shall be output. </font></span><span lang="en-GB"><font face="Thorndale">Output can
1344be skipped at the beginning of a simulation using parameter <a href="#skip_time_do2d_xz">skip_time_do2d_xz</a>, which
1345has zero value by default. </font></span><span lang="en-GB"></span><span lang="en-GB"><font face="Thorndale">Reference time is the beginning of
1346the simulation, i.e. output takes place at times t = <b>skip_time_do2d_xz
1347+ dt_do2d_xz</b>,
1348<span style="font-weight: bold;">skip_time_do2d_xz</span>
1349+ 2*<b>dt_do2d_xz</b>, <span style="font-weight: bold;">skip_time_do2d_xz</span>
1350+ 3*<b>dt_do2d_xz</b>, etc. The actual output times
1351can deviate from these theoretical values (see </font></span><a href="#dt_dopr_zeitpunkte"><span lang="en-GB"><font face="Thorndale">dt_dopr</font></span></a><span lang="en-GB"><font face="Thorndale">).<br>
1352</font></span></p> <p><span lang="en-GB"><font face="Thorndale">Parameter </font></span><a href="#do2d_at_begin"><span lang="en-GB"><font face="Thorndale">do2d_at_begin</font></span></a>
1353has to be used if an additional output is wanted at the start of a run <span lang="en-GB"><font face="Thorndale">(thus at
1354the time t = 0 or at the
1355respective starting times of restart runs).</font></span> </p>
1356</td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="dt_do2d_yz"></a><b>dt_do2d_yz</b></p>
1357</td> <td style="vertical-align: top;">R</td>
1358<td style="vertical-align: top;"><i>value of
1359&nbsp;<a href="chapter_4.2.html#dt_data_output">dt_data_<br>output</a></i></td>
1360<td style="vertical-align: top;"> <p lang="en-GB"><font face="Thorndale"><font face="Thorndale, serif">Temporal
1361interval</font> at which&nbsp;vertical cross section data
1362(yz) shall be output (</font>in s<font face="Thorndale">).&nbsp;
1363</font> </p> <p><span lang="en-GB"><font face="Thorndale">If output of
1364horizontal cross sections is switched on (see </font></span><a href="#data_output"><span lang="en-GB"><font face="Thorndale">data_output</font></span></a>
1365<span lang="en-GB"><font face="Thorndale">and
1366</font></span><a href="#section_yz"><span lang="en-GB"><font face="Thorndale">section_yz</font></span></a><span lang="en-GB"><font face="Thorndale">),
1367this parameter can be used to assign the temporal interval at which
1368cross section data shall be output. </font></span><span lang="en-GB"><font face="Thorndale">Output can
1369be skipped at the beginning of a simulation using parameter <a href="#skip_time_do2d_yz">skip_time_do2d_yz</a>, which
1370has zero value by default. </font></span><span lang="en-GB"></span><span lang="en-GB"></span><span lang="en-GB"><font face="Thorndale">Reference
1371time is the beginning of
1372the simulation, i.e. output takes place at times t = <b>skip_time_do2d_yz
1373+ dt_do2d_yz</b>,
1374<span style="font-weight: bold;">skip_time_do2d_yz</span>
1375+ 2*<b>dt_do2d_yz</b>, <span style="font-weight: bold;">skip_time_do2d_yz
1376</span>+ 3*<b>dt_do2d_yz</b>, etc. The actual output
1377times
1378can deviate from these theoretical values (see </font></span><a href="#dt_dopr_zeitpunkte"><span lang="en-GB"><font face="Thorndale">dt_dopr</font></span></a><span lang="en-GB"><font face="Thorndale">).<br>
1379</font></span></p> <p><span lang="en-GB"><font face="Thorndale">Parameter </font></span><a href="#do2d_at_begin"><span lang="en-GB"><font face="Thorndale">do2d_at_begin</font></span></a>
1380has to be used if an additional output is wanted at the start of a run <span lang="en-GB"><font face="Thorndale">(thus at
1381the time t = 0 or at the
1382respective starting times of restart runs).</font></span> </p>
1383</td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="dt_do3d"></a><b>dt_do3d</b></p>
1384</td> <td style="vertical-align: top;">R</td>
1385<td style="vertical-align: top;"><i>value of
1386&nbsp;<a href="chapter_4.2.html#dt_data_output">dt_data_<br>output</a></i></td>
1387<td style="vertical-align: top;"> <p lang="en-GB"><font face="Thorndale"><font face="Thorndale, serif">Temporal
1388interval</font> at which 3d volume data shall be output (</font>in
1389<font face="Thorndale">s).&nbsp; </font> </p>
1390<p><span lang="en-GB"><font face="Thorndale">If
1391output of
13923d-volume data is switched on (see </font></span><font><a href="#data_output"><span lang="en-GB"><font face="Thorndale">data_output</font></span></a>)<span style="font-family: thorndale;">, this parameter can be used
1393to assign
1394th</span></font><span lang="en-GB"><font face="Thorndale">e temporal
1395interval at which 3d-data shall be output. </font></span><span lang="en-GB"><font face="Thorndale">Output can
1396be skipped at the beginning of a simulation using parameter <a href="#skip_time_do3d">skip_time_do3d</a>, which has
1397zero value by default. </font></span><span lang="en-GB"></span><span lang="en-GB"></span><span lang="en-GB"></span><span lang="en-GB"><font face="Thorndale">Reference
1398time is the
1399beginning of the simulation, i.e. output takes place at times t = <b>skip_time_do3d
1400+ dt_do3d</b>,
1401<span style="font-weight: bold;">skip_time_do3d</span>
1402+ 2*<b>dt_do3d</b>, <span style="font-weight: bold;">skip_time_do3d</span>
1403+ 3*<b>dt_do3d</b>, etc. The actual output times can
1404deviate from these theoretical values (see </font></span><a href="#dt_dopr_zeitpunkte"><span lang="en-GB"><font face="Thorndale">dt_dopr</font></span></a><span lang="en-GB"><font face="Thorndale">). <br>
1405</font></span></p> <p><span lang="en-GB"><font face="Thorndale">Parameter </font></span><a href="#do3d_at_begin"><span lang="en-GB"><font face="Thorndale">do3d_at_begin</font></span></a>
1406has to be used if an additional output is wanted at the start of a run <span lang="en-GB"><font face="Thorndale">(thus at
1407the time t = 0 or at the
1408respective starting times of restart runs).</font></span> </p>
1409</td> </tr> <tr><td style="vertical-align: top;"><a name="dt_max"></a><span style="font-weight: bold;">dt_max</span></td><td style="vertical-align: top;">R</td><td style="vertical-align: top;"><span style="font-style: italic;">20.0</span></td><td>Maximum
1410allowed value of the timestep (in s).<br><br>By default,
1411the maximum timestep is restricted to be 20 s. This might be o.k. for
1412simulations of any kind of atmospheric turbulence but may have to be
1413changed for other situations.</td></tr><tr> <td style="vertical-align: top;"> <p><a name="dt_restart"></a><b>dt_restart</b></p>
1414</td> <td style="vertical-align: top;">R</td>
1415<td style="vertical-align: top;"><i>9999999.9</i></td>
1416<td style="vertical-align: top;"> <p lang="en-GB"><font face="Thorndale"><font face="Thorndale, serif">Temporal
1417interval</font> at which a new
1418restart run is to be carried out (</font>in <font face="Thorndale">s). </font> </p> <p><span lang="en-GB"><font face="Thorndale">For a
1419description
1420how to assign restart times manually see run time parameter </font></span><a href="#restart_time"><span lang="en-GB"><font face="Thorndale">restart_time</font></span></a><span lang="en-GB"><font face="Thorndale">. <span style="font-weight: bold;">dt_restart</span>
1421does not show any effect, if <span style="font-weight: bold;">restart_time</span>
1422has not been set.</font></span> </p> </td> </tr>
1423<tr> <td style="vertical-align: top;"> <p><a name="dt_run_control"></a><b>dt_run_control</b></p>
1424</td> <td style="vertical-align: top;">R</td>
1425<td style="vertical-align: top;"><i>60.0</i></td>
1426<td style="vertical-align: top;"> <p lang="en-GB"><font face="Thorndale"><font face="Thorndale, serif">Temporal
1427interval</font> at which run control
1428output is to be made (</font>in <font face="Thorndale">s).&nbsp;
1429</font> </p> <p><span lang="en-GB"><font face="Thorndale">Run control
1430information is output to the local ASCII-file </font></span><a href="chapter_3.4.html#RUN_CONTROL"><span lang="en-GB"><font face="Thorndale">RUN_CONTROL</font></span></a><span lang="en-GB"><font face="Thorndale">. At each
1431output time, one line
1432with information about the size of the time step, maximum speeds, total
1433kinetic energy etc. is written to this file. Reference time is the
1434beginning of the simulation, i.e. output takes place at times t = <b>dt_run_control</b>,
14352*<b>dt_run_control</b>, 3*<b>dt_run_control</b>,
1436etc., and always at
1437the beginning of a model run (thus at the time t = 0 or at the
1438respective starting times of restart runs). The actual output times can
1439deviate from these theoretical values (see </font></span><a href="#dt_dopr_zeitpunkte"><span lang="en-GB"><font face="Thorndale">dt_dopr</font></span></a><span lang="en-GB"><font face="Thorndale">).<br>
1440</font></span></p> <p><span lang="en-GB"><font face="Thorndale">Run control
1441information is output after each time step can be achieved via <b>dt_run_control</b>
1442= <i>0.0</i>.</font></span> </p> </td>
1443</tr> <tr> <td style="vertical-align: top;"><p><a name="end_time"></a><b>end_time</b></p>
1444</td> <td style="vertical-align: top;">R</td>
1445<td style="vertical-align: top;"><i>0.0</i></td>
1446<td style="vertical-align: top;"> <p lang="en-GB"><font face="Thorndale">Simulation time of the 3D
1447model (</font>in <font face="Thorndale">s).&nbsp;
1448</font> </p> <p><span lang="en-GB"><font face="Thorndale">The simulation time
1449is starting from the beginning of the initialization run (t = 0), not
1450starting from the beginning of the respective restart run.</font></span>
1451</p> </td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="force_print_header"></a><b>force_print_header</b></p>
1452</td> <td style="vertical-align: top;">L</td>
1453<td style="vertical-align: top;"><i>.F.</i></td>
1454<td style="vertical-align: top;"> <p>Steering of
1455header output to the local file <a href="chapter_3.4.html#RUN_CONTROL">RUN_CONTROL</a>.&nbsp;
1456</p> <p>By default, informations about the model
1457parameters in use are
1458output to the beginning of file RUN_CONTROL for initial runs only
1459(these informations are identical to that which are output to the local
1460file <a href="chapter_3.4.html#HEADER">HEADER</a>).
1461With <b>force_print_header</b> = <i>.T.</i>,
1462these informations are
1463also output to <a href="chapter_3.4.html#RUN_CONTROL">RUN_CONTROL</a>
1464at restart runs.</p> </td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="mg_cycles"></a><b>mg_cycles</b></p>
1465</td> <td style="vertical-align: top;">I</td>
1466<td style="vertical-align: top;"><i>-1</i></td>
1467<td style="vertical-align: top;"> <p>Number of
1468cycles to be used with the multi-grid scheme.<br> <br>
1469This parameter determines the number of cycles to be carried out in the
1470multi-grid method used for solving the Poisson equation for
1471perturbation pressure (see <a href="#psolver">psolver</a>).
1472The type of the cycles can be set with <a href="#cycle_mg">cycle_mg</a>.<br>
1473</p> <br>By default (<b>mg_cyles</b> = <i>-
14741</i>), the
1475number of cycles
1476depends on the requested accuracy of the scheme (see <a href="#residual_limit">residual_limit</a>)
1477and may vary from time step to time step. In this case, the CPU time
1478for a run will be difficult to estimate, since it heavily depends on
1479the total number of the cycles to be carried out.<br> <br>
1480By assigning <b>mg_cycles</b> a value (&gt;=<span style="font-style: italic;">1</span>), the number of
1481cycles can be
1482fixed so that the CPU time can be clearly estimated. <br> <br>
1483<b>Note:</b> When using a fixed number of cycles, the user
1484must
1485examine the local file <a href="chapter_3.4.html#RUN_CONTROL">RUN_CONTROL</a>
1486regularly to check whether the divergence of the velocity field is
1487sufficiently reduced by the pressure solver. It should be reduced at
1488least by two orders of magnitude. For cyclic boundary conditions along
1489both horizontal directions (see <a href="chapter_4.1.html#bc_lr">bc_lr</a>
1490and <a href="chapter_4.1.html#bc_ns">bc_ns</a>) <span style="font-weight: bold;">mg_cycles</span> = <span style="font-style: italic;">2</span> is typically a
1491good choice, for
1492non-cyclic lateral boundary conditions <span style="font-weight: bold;">mg_cycles</span>
1493= <span style="font-style: italic;">4</span> may be
1494sufficient.</td> </tr> <tr> <td style="vertical-align: top;"><a name="mg_switch_to_pe0_level"></a><b>mg_switch_to_pe0_<br>
1495level</b></td> <td style="vertical-align: top;">I</td>
1496<td style="vertical-align: top;"><br> </td> <td style="vertical-align: top;">Grid
1497level at which data shall be gathered on PE0.<br> <br>
1498In case of a run using several PEs and the multigrid method for solving
1499the Poisson equation for perturbation pressure (see <a href="#psolver">psolver</a>),
1500the value of this parameter defines on which grid level the data are
1501gathered on PE0 in order to allow for a further coarsening of the grid.
1502The finest grid defines the largest grid level. By default, the
1503gathering level is determined automatically and displayed in file <a href="chapter_3.4.html#RUN_CONTROL">RUN_CONTROL</a>.
1504It is only possible to gather data from a level larger than the one
1505determined automatically. A test run may be neccessary to determine
1506this level.</td> </tr> <tr> <td style="vertical-align: top;"><a name="netcdf_64bit"></a><span style="font-weight: bold;">netcdf_64bit</span><br>
1507</td> <td style="vertical-align: top;">L<br> </td>
1508<td style="vertical-align: top;"><span style="font-style: italic;">.F.</span><br> </td>
1509<td style="vertical-align: top;">NetCDF files will have 64
1510bit offset format.<br><br>By
1511default, the maximum file size of the NetCDF files opened by PALM is 2
1512GByte. Using netcdf_64bit = .TRUE. allows file sizes larger than 2
1513GByte.<br><br>The 64 bit offset format can be separately
1514switched off for those NetCDF files containing 3d volume date (<span style="font-family: Courier New,Courier,monospace;">DATA_3D_NETCDF</span>,
1515<span style="font-family: Courier New,Courier,monospace;">DATA_3D_AV_NETCDF</span>)
1516using <a href="#netcdf_64bit_3d">netcdf_64bit_3d</a>.<br><br><span style="font-weight: bold;">Warning:</span><br>Some
1517(PD or commercial) software may not support the 64 bit offset format.<br>
1518</td> </tr><tr><td style="vertical-align: top;"><a name="netcdf_64bit_3d"></a><span style="font-weight: bold;">netcdf_64bit_3d</span></td><td style="vertical-align: top;">L</td><td style="vertical-align: top;">.T.</td><td style="vertical-align: top;">NetCDF files containing 3d
1519volume data will have 64 bit offset format.<br><br>This
1520switch&nbsp;only comes into effect if <a href="#netcdf_64bit">netcdf_64bit</a>
1521= .TRUE.. It allows to switch off separately the 64 bit offset format
1522for those NetCDF files containing 3d volume data (<span style="font-family: Courier New,Courier,monospace;">DATA_3D_NETCDF</span>,
1523<span style="font-family: Courier New,Courier,monospace;">DATA_3D_AV_NETCDF</span>).</td></tr><tr>
1524<td style="vertical-align: top;"> <p><a name="ngsrb"></a><b>ngsrb</b></p> </td>
1525<td style="vertical-align: top;">I</td> <td style="vertical-align: top;"><i>2</i></td>
1526<td style="vertical-align: top;">Grid
1527level at which data shall be gathered on PE0.<br> <br>
1528In case of a run using several PEs and the multigrid method for solving
1529the Poisson equation for perturbation pressure (see <a href="#psolver">psolver</a>),
1530the value of this parameter defines on which grid level the data are
1531gathered on PE0 in order to allow for a further coarsening of the grid.
1532The finest grid defines the largest grid level. By default, the
1533gathering level is determined automatically and displayed in file <a href="chapter_3.4.html#RUN_CONTROL">RUN_CONTROL</a>.
1534It is only possible to gather data from a level larger than the one
1535determined automatically. A test run may be neccessary to determine
1536this level.</td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="normalizing_region"></a><b>normalizing_region</b></p>
1537</td> <td style="vertical-align: top;">I</td>
1538<td style="vertical-align: top;"><span style="font-style: italic;">0</span><br> </td>
1539<td style="vertical-align: top;"> <p>Determines the
1540subdomain from which the normalization
1541quantities are calculated.&nbsp; </p> <p>If output
1542data of the horizontally averaged vertical profiles
1543(see <a href="#data_output_pr">data_output_pr</a>)
1544is to be normalized (see <a href="#cross_normalized_x">cross_normalized_x</a>,
1545<a href="#cross_normalized_y">cross_normalized_y</a>),
1546the respective normalization quantities are by default calculated from
1547the averaged data of the total model domain (<b>normalizing_region</b>
1548= <i>0</i>) and are thus representative for the total
1549domain. Instead
1550of that, normalization quantities can also be calculated for a
1551subdomain. The wanted subdomain can be given with the parameter <span style="font-weight: bold;">normalizing_region</span>,
1552where <i>1</i>
1553&lt;= <b>normalizing_region</b> &lt;= <i>9 </i>must
1554hold. These
1555quantities are then used for normalizing of all profiles (even for that
1556of the total domain).</p> </td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="nsor"></a><b>nsor</b></p>
1557</td> <td style="vertical-align: top;">I</td>
1558<td style="vertical-align: top;"><i>20</i></td>
1559<td style="vertical-align: top;"> <p>Number of
1560iterations to be used with the SOR-scheme.&nbsp; </p> <p>This
1561parameter is only effective if the SOR-scheme is selected
1562as pressure solver (<a href="#psolver">psolver</a>
1563= <span style="font-style: italic;">'sor'</span>).
1564The number of
1565iterations necessary for a sufficient convergence of the scheme depends
1566on the grid point numbers and is to be determined by appropriate test
1567runs (the default value will not at all be sufficient for larger grid
1568point numbers). The number of iterations used for the first call of the
1569SOR-scheme (t = 0) is determined via the parameter <a href="chapter_4.1.html#nsor_ini">nsor_ini</a>.</p>
1570</td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="nz_do3d"></a><b>nz_do3d</b></p>
1571</td> <td style="vertical-align: top;">I</td>
1572<td style="vertical-align: top;"><i>nz+1</i></td>
1573<td style="vertical-align: top;"> Limits the output of 3d
1574volume data along the vertical direction (grid point index k).<br><br>By
1575default, data for all grid points along z are output. The parameter <span style="font-weight: bold;">nz_do3d</span>
1576can be used to limit the output up to a certain vertical grid point
1577(e.g. in order to reduce the amount of output data). It affects all
1578output of volume data ("normal" output to file, see <a href="#data_output">data_output</a>, as well as output
1579for <span style="font-weight: bold;">dvrp</span>-software,
1580see <a href="#mode_dvrp">mode_dvrp</a>).</td>
1581</tr> <tr> <td style="vertical-align: top;"><p><a name="omega_sor"></a><b>omega_sor</b></p>
1582</td> <td style="vertical-align: top;">R</td>
1583<td style="vertical-align: top;"><i>1.8</i></td>
1584<td style="vertical-align: top;"> <p>Convergence
1585factor to be used with the the SOR-scheme.&nbsp; </p> <p>If
1586the SOR-scheme is selected (<a href="#psolver">psolver</a>
1587= <span style="font-style: italic;">'sor'</span>),
1588this parameter
1589determines the value of the convergence factor, where <i>1.0</i>
1590&lt;= <b>omega_sor</b> &lt; <i>2.0 </i>.
1591The optimum value of <b>omega_sor</b>
1592depends on the number of grid points along the different directions in
1593space. For non-equidistant grids it can only be determined by
1594appropriate test runs.</p> </td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="prandtl_number"></a><b>prandtl_number</b></p>
1595</td> <td style="vertical-align: top;">R</td>
1596<td style="vertical-align: top;"><i>1.0</i></td>
1597<td style="vertical-align: top;"> <p>Ratio of the
1598eddy diffusivities for momentum and heat (K<sub>m</sub>/K<sub>h</sub>).&nbsp;
1599</p> <p>For runs with constant eddy diffusivity (see <a href="chapter_4.1.html#km_constant">km_constant</a>),
1600this parameter can be used to assign the Prandtl number (ratio K<sub>m</sub>
1601/ K<sub>h</sub>).</p> </td> </tr> <tr><td style="vertical-align: top;"><a name="precipitation_amount_interval"></a><span style="font-weight: bold;">precipitation_amount_</span><br style="font-weight: bold;"><span style="font-weight: bold;">interval</span></td><td style="vertical-align: top;">R</td><td style="vertical-align: top;"><i>value of
1602&nbsp;<a href="chapter_4.2.html#dt_do2d_xy">dt_do2d_<br>xy</a></i></td><td style="vertical-align: top;"><p lang="en-GB"><font face="Thorndale"><font face="Thorndale, serif">Temporal
1603interval</font> for which the precipitation amount (in mm) shall be calculated and output (</font>in <font face="Thorndale">s).&nbsp;
1604</font> </p> <p><span lang="en-GB"></span><a href="chapter_4.2.html#data_output"><span lang="en-GB"></span></a><span lang="en-GB"></span><a href="chapter_4.2.html#section_xy"><span lang="en-GB"></span></a><span lang="en-GB"><font face="Thorndale">This
1605parameter requires <a href="chapter_4.1.html#precipitation">precipitation</a> = <span style="font-style: italic;">.TRUE.</span>.&nbsp;</font></span><span lang="en-GB"></span><span lang="en-GB"><font face="Thorndale"><span style="font-weight: bold;"></span><span style="font-weight: bold;"></span>The interval must be smaller or equal than the output interval for 2d horizontal cross sections given by </font></span><a href="chapter_4.2.html#dt_do2d_xy"><span lang="en-GB"><font face="Thorndale">dt_do2d_xy</font></span></a><span lang="en-GB"><font face="Thorndale">). The output of the precipitation amount also requires setting of <a href="chapter_4.2.html#data_output">data_output</a> =<span style="font-style: italic;"> 'pra*'</span>.<br>
1606</font></span></p> <span lang="en-GB"></span></td></tr><tr>
1607<td style="vertical-align: top;"> <p><a name="profile_columns"></a><b>profile_columns</b></p>
1608</td> <td style="vertical-align: top;">I</td>
1609<td style="vertical-align: top;"><i>3</i></td>
1610<td style="vertical-align: top;"> <p>Number of
1611coordinate systems to be plotted<span style="font-weight: bold;"></span>
1612in one row by <span style="font-weight: bold;">profil</span>.&nbsp;
1613</p> <p>This parameter only applies for &nbsp;<a href="chapter_4.2.html#data_output_format">data_output_format</a>
1614= <span style="font-style: italic;">'profil'</span>.</p><p>It
1615determines the layout of plots of
1616horizontally averaged profiles (<a href="#data_output_pr">data_output_pr</a>)
1617when plotted with the plot software <span style="font-weight: bold;">profil</span>.
1618Generally, the number and sequence of coordinate systems (panels) to be
1619plotted on one page are
1620determined by <a href="#cross_profiles">cross_profiles</a>.
1621<b>profile_columns</b>
1622determines how many panels are to be
1623arranged next to each other in one row (number of columns). The
1624respective number of rows on a page is assigned by <a href="#profile_rows">profile_rows</a>.
1625According to their order given by <a href="#data_output_pr">data_output_pr</a>,
1626the panels are arranged beginning in the top row from left to right and
1627then continued in the following row. If the number of panels cranz
1628&gt; <b>profile_columns</b> * <b>profile_rows</b>,
1629the remaining
1630panels are drawn on an additional page. If cranz &lt; <b>profile_columns</b>,
1631then <b>profile_columns</b> = cranz is automatically set.
1632If
1633row&nbsp; contains any panel, then the value of <b>profile_rows</b>
1634is reduced automatically.</p> </td> </tr> <tr>
1635<td style="vertical-align: top;"> <p><a name="profile_rows"></a><b>profile_rows</b></p>
1636</td> <td style="vertical-align: top;">I</td>
1637<td style="vertical-align: top;"><i>2</i></td>
1638<td style="vertical-align: top;"> <p>Number of rows
1639of coordinate systems to be plotted on one page
1640by <span style="font-weight: bold;">profil</span>.&nbsp;
1641</p> <p>This parameter only applies for &nbsp;<a href="chapter_4.2.html#data_output_format">data_output_format</a>
1642= <span style="font-style: italic;">'profil'</span>.</p><p>It
1643determines the layout of plots of horizontally averaged
1644profiles. See <a href="#profile_columns">profile_columns</a>.</p>
1645</td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="psolver"></a><b>psolver</b></p>
1646</td> <td style="vertical-align: top;">C * 10</td>
1647<td style="vertical-align: top;"><i>'poisfft'</i></td>
1648<td style="vertical-align: top;"> <p>Scheme to be
1649used to solve the Poisson equation for the
1650perturbation pressure.&nbsp; </p> <br>
1651The user can choose between the following schemes:<br> <table style="text-align: left; width: 100%;" cellpadding="2" cellspacing="2"> <tbody> <tr> <td style="vertical-align: top;"><i>poisfft</i></td>
1652<td style="vertical-align: top;">Direct method using FFT
1653along x and y, solution of a
1654tridiagonal matrix along z, and backward
1655FFT (see Siano, institute reports, volume 54). The FFT routines to be
1656used can be determined via the initialization parameter <a href="chapter_4.1.html#fft_method">fft_method</a>.<br>
1657This solver is specially optimized for 1d domain decompositions.
1658Vectorization is optimized for domain decompositions along x only.</td>
1659</tr> <tr> <td style="vertical-align: top;"><p><i>poisfft_</i>
1660<br> <i>hybrid</i></p>
1661</td> <td style="vertical-align: top;">Direct
1662method using FFT
1663along x and y, solution of a
1664tridiagonal matrix along z, and backward
1665FFT (see Siano, institute reports, volume 54). The FFT routines to be
1666used can be determined via the initialization parameter <a href="chapter_4.1.html#fft_method">fft_method</a>.<br>
1667This solver is specially optimized for 1d domain decompositions.
1668Vectorization is optimized for domain decompositions along x only.</td>
1669</tr> <tr> <td style="vertical-align: top;"><i>multigrid</i></td>
1670<td style="vertical-align: top;"> <p>Multi-grid
1671scheme (see Uhlenbrock, diploma thesis). v-
1672and
1673w-cycles (see <a href="#cycle_mg">cycle_mg</a>)
1674are implemented. The convergence of the iterative scheme can be
1675steered by the number of v-/w-cycles to be carried out for each call of
1676the scheme (<a href="#mg_cycles">mg_cycles</a>)
1677and by the number of Gauss-Seidel iterations (see <a href="#ngsrb">ngsrb</a>)
1678to be carried out on each grid level. Instead the requested accuracy
1679can be given via <a href="#residual_limit">residual_limit</a>.
1680<span style="font-weight: bold;">This is the default!</span>
1681The
1682smaller this limit is, the more cycles have to be carried out in this
1683case and the number of cycles may vary from timestep to timestep.</p>
1684<br>If <a href="#mg_cycles">mg_cycles</a>
1685is set to its optimal value, the computing time of the
1686multi-grid scheme amounts approximately to that of the direct solver <span style="font-style: italic;">poisfft</span>, as long as
1687the number of
1688grid points in the three directions
1689of space corresponds to a power-of-two (2<sup>n</sup>)
1690where <i>n</i> &gt;= 5 must hold. With large <i>n,
1691</i>the
1692multi-grid scheme can even be faster than the direct solver (although
1693its accuracy is several orders of magnitude worse, but this does not
1694affect the accuracy of the simulation). Nevertheless, the user should
1695always carry out some test runs in order to find out the optimum value
1696for <a href="#mg_cycles">mg_cycles</a>,
1697because the CPU time of a run very critically depends on this
1698parameter. <p>This scheme requires that the number of grid
1699points of
1700the
1701subdomains (or of the total domain, if only one PE is uesd) along each
1702of the directions can at least be devided once by 2 without rest.</p>
1703With parallel runs, starting from a certain grid level the
1704data of the subdomains are possibly gathered on PE0 in order to allow
1705for a further coarsening of the grid. The grid level for gathering can
1706be manually set by <a href="#mg_switch_to_pe0_level">mg_switch_to_pe0_level</a>.<br>
1707<p>Using this procedure requires the subdomains to be of
1708identical size (see <a href="chapter_4.1.html#grid_matching">grid_matching</a>).</p>
1709</td> </tr> <tr> <td style="vertical-align: top;"><i>sor</i></td>
1710<td style="vertical-align: top;">Successive over
1711relaxation
1712method (SOR). The convergence of
1713this
1714iterative scheme is steered with the parameters <a href="#omega_sor">omega_sor</a>,
1715<a href="chapter_4.1.html#nsor_ini">nsor_ini</a>
1716and <a href="chapter_4.1.html#nsor">nsor</a>.&nbsp;
1717<br>Compared to the direct method and the multi-grid method, this
1718scheme
1719needs substantially
1720more computing time. It should only be used for test runs, e.g. if
1721errors in the other pressure solver methods are assumed.</td> </tr>
1722</tbody> </table> <br>In order to speed-up
1723performance, the Poisson equation is by default
1724only solved at the last substep of a multistep Runge-Kutta scheme (see <a href="#call_psolver_at_all_substeps">call_psolver
1725at_all_substeps</a> and <a href="chapter_4.1.html#timestep_scheme">timestep_scheme</a>).&nbsp;
1726</td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="rayleigh_damping_factor"></a><b>rayleigh_damping</b>
1727<br> <b>_factor</b></p> </td> <td style="vertical-align: top;">R</td> <td style="vertical-align: top;"><i>0.0 or</i><br>
1728<i>0.01</i></td> <td style="vertical-align: top;">
1729<p>Factor for Rayleigh damping.&nbsp; </p> <p>A
1730so-called Rayleigh damping is applied to all prognostic
1731variables if a non-zero value is assigned to <b>rayleigh_damping_factor</b>.&nbsp;
1732If switched on, variables are forced towards the value of their
1733respective basic states (e.g. the geostrophic wind). The intensity of
1734damping is controlled by the value the <b>rayleigh_damping_factor</b>
1735is assigned to.
1736The damping starts weakly at a height defined by <a href="#rayleigh_damping_height">rayleigh_damping_height</a>
1737and rises according to a sin<sup>2</sup>-function to its
1738maximum value
1739at
1740the top boundary. </p> <p>This method
1741effectively damps gravity waves, caused by boundary layer convection,
1742which may spread out vertically in the inversion layer and which are
1743reflected&nbsp; at the top
1744boundary. This particularly happens with the upstream-spline scheme
1745switched on (see <a href="chapter_4.1.html#momentum_advec">momentum_advec</a>
1746or <a href="chapter_4.1.html#scalar_advec">scalar_advec</a>).
1747Therefore, with this scheme the Rayleigh damping is switched on (<b>rayleigh_damping_factor</b>
1748= <i>0.01</i>) by default. Otherwise it remains switched
1749off.&nbsp; </p> <p>The Rayleigh damping factor must
1750hold the condition <i>0.0</i>
1751&lt;= <b>rayleigh_damping_factor</b>
1752&lt;= <i>1.0</i>. Large values (close to <span style="font-style: italic;">1.0</span>) can cause
1753numerical instabilities.</p> </td> </tr> <tr>
1754<td style="vertical-align: top;"> <p><a name="rayleigh_damping_height"></a><b>rayleigh_damping</b>
1755<br> <b>_height</b></p> </td> <td style="vertical-align: top;">R</td> <td style="vertical-align: top;"> <p><i>2/3 *</i>
1756<br><span style="font-style: italic;">zu</span><i style="font-style: italic;">(nz)</i></p>
1757</td> <td style="vertical-align: top;"> <p>Height
1758where the Rayleigh damping starts (in m).&nbsp; </p> <p>With
1759Rayleigh damping switched on (see <a href="#rayleigh_damping_factor">rayleigh_damping_factor</a>),
1760this parameter determines the range where damping is applied. By
1761default, Rayleigh damping will be applied in the upper third of the
1762model
1763domain.</p> </td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="residual_limit"></a><b>residual_limit</b></p>
1764</td> <td style="vertical-align: top;">R</td>
1765<td style="vertical-align: top;"><i>1.0E-6</i></td>
1766<td style="vertical-align: top;"> <p>Largest
1767residual permitted for the multi-grid scheme (in s<sup>-2</sup>m<sup>-3</sup>).&nbsp;
1768</p> <p>This is a parameter to steer the accuracy of the
1769multi-grid
1770scheme (see <a href="#psolver">psolver</a>).
1771The assigned cycle (v- or w-cycle, see <a href="#mg_cycles">mg_cycles</a>)
1772is passed through until the residual falls below the limit given by <span style="font-weight: bold;">residual_limit</span>. If
1773this
1774is not the case after 1000 cycles, the PALM aborts with a corresponding
1775error message.</p> <p>The reciprocal value of this
1776parameter can be interpreted as
1777a factor by the divergence of the provisional
1778velocity field is approximately reduced after the multi-grid scheme has
1779been applied (thus the default value causes a reduction of the
1780divergence by approx. 6 orders of magnitude).&nbsp; </p> </td>
1781</tr> <tr> <td style="vertical-align: top;"><p><a name="restart_time"></a><b>restart_time</b></p>
1782</td> <td style="vertical-align: top;">R</td>
1783<td style="vertical-align: top;"><i>9999999.9</i></td>
1784<td style="vertical-align: top;"> <p>Simulated time
1785after which a restart run is to be carried out
1786(in s). </p> <p>The simulated time refers to the
1787beginning of the
1788initial run (t = 0), not to the beginning of the respective
1789restart run. Restart runs can additionally be forced to be carried out
1790in regular intervals using the run time parameter <a href="#dt_restart">dt_restart</a>. </p> <p><span style="font-weight: bold;">Note:</span><br>
1791A successful operation of this parameter requires additional
1792modifications in the <span style="font-weight: bold;">mrun</span>-call
1793for the respective run (see <a href="chapter_3.3.html">chapter
17943.3</a>).<br> </p> <p>The choice of <b>restart_time</b>
1795or <b>dt_restart</b> does
1796not override the automatic start of restart runs in case that the job
1797runs out of CPU time. <br> </p> </td> </tr>
1798<tr> <td style="vertical-align: top;"> <p><a name="section_xy"></a><b>section_xy</b></p>
1799</td> <td style="vertical-align: top;">I(100)<br>
1800</td> <td style="vertical-align: top;"><span style="font-style: italic;">no section</span><br>
1801</td> <td style="vertical-align: top;"> <p lang="en-GB"><font face="Thorndale">Position
1802of&nbsp;cross section(s) for&nbsp;output of 2d horizontal cross
1803sections (grid point index k).&nbsp; </font> </p> <p><span lang="en-GB"><font face="Thorndale">If output
1804of
1805horizontal cross sections is selected (see </font></span><a href="chapter_4.2.html#data_output"><span lang="en-GB"><font face="Thorndale">data_output</font></span></a><span lang="en-GB"><font face="Thorndale">), this
1806parameter can be used to
1807define the position(s) of the cross section(s). Up to 100 positions of
1808cross sections can be selected by assigning <b>section_xy</b>
1809the
1810corresponding vertical grid point index/indices k of the requested
1811cross section(s). The exact location (height level) of the cross
1812section depends on the variable for which the output is made: zu(k) for
1813scalars and horizontal velocities, zw(k) for the vertical velocity.
1814Information about the exact location of the cross section is contained
1815in the NetCDF output file (if the default NetCDF output is switched on;
1816see <a href="#data_output_format">data_output_format</a>).</font></span></p><p><span lang="en-GB"><font face="Thorndale">Assigning <span style="font-weight: bold;">section_xy</span> = <span style="font-style: italic;">-1</span>
1817creates the output of horizontal cross sections averaged along z. In
1818the
1819NetCDF output file these (averaged) cross sections are given the
1820z-coordinate <span style="font-style: italic;">-1.0</span>.</font></span></p><p><span lang="en-GB"></span><span lang="en-GB"><font face="Thorndale">Assignments to <b>section_xy</b>
1821does not effect the output of horizontal cross sections of variable u<sub>*</sub>
1822and theta<sub>*</sub> and the liquid water path lwp*. For
1823these quantities always only one cross
1824section (for z=zu(1)) is output.</font></span></p><span lang="en-GB"><font face="Thorndale">In case of <span style="font-weight: bold;">data_output_format</span> =
1825<span style="font-style: italic;">'iso2d'</span> and
1826if several cross sections are selected (e.g. <b>section_xy</b>
1827= <i>1</i>, <i>10</i>, <i>15</i>),
1828then the respective data are
1829successively written to file. The output order follows the order given
1830by <b>section_xy</b>.&nbsp;</font></span></td>
1831</tr> <tr> <td style="vertical-align: top;"><p><a name="section_xz"></a><b>section_xz</b></p>
1832</td> <td style="vertical-align: top;">I(100)<br>
1833</td> <td style="vertical-align: top;"><span style="font-style: italic;">no section</span></td>
1834<td style="vertical-align: top;"> <p lang="en-GB"><font face="Thorndale">Position of&nbsp;cross section(s)
1835for&nbsp;output of 2d (xz) vertical cross sections (grid point
1836index j).&nbsp; </font> </p> <span lang="en-GB"><font face="Thorndale">If output of
1837vertical xz cross sections is selected (see </font></span><a href="chapter_4.2.html#data_output"><span lang="en-GB"><font face="Thorndale">data_output</font></span></a><span lang="en-GB"><font face="Thorndale">), this
1838parameter can be used to
1839define the position(s) of the cross section(s). Up to 100 positions of
1840cross sections can be selected by assigning <b>section_xz</b>
1841the
1842corresponding horizontal grid point index/indices j of the requested
1843cross section(s). The exact position (in y-direction) of the cross
1844section is given by j*</font></span><a href="chapter_4.1.html#dy"><span lang="en-GB"><font face="Thorndale">dy</font></span></a> <span lang="en-GB"><font face="Thorndale">or (j-0.5)*</font></span><a href="chapter_4.1.html#dy"><span lang="en-GB"><font face="Thorndale">dy</font></span></a><span lang="en-GB"><font face="Thorndale">, depending
1845on which grid the output quantity is defined. However, in
1846the&nbsp;NetCDF output file </font></span><span lang="en-GB"><font face="Thorndale">(if the
1847default NetCDF output is switched on; see <a href="chapter_4.2.html#data_output_format">data_output_format</a>)
1848no distinction is made between the quantities and j*<span style="font-weight: bold;">dy</span> is used for all
1849positions.<br><br>Assigning <span style="font-weight: bold;">section_xz</span> = <span style="font-style: italic;">-1</span>
1850creates the output of vertical cross sections averaged along y. In the
1851NetCDF output file these (averaged) cross sections are given the
1852y-coordinate <span style="font-style: italic;">-1.0</span>.<br></font></span><span lang="en-GB"><font face="Thorndale"><br></font></span><span lang="en-GB"><font face="Thorndale">In case of <span style="font-weight: bold;">data_output_format</span> =
1853<span style="font-style: italic;">'iso2d'</span> and
1854</font></span><span lang="en-GB"><font face="Thorndale">if several cross sections are
1855selected (e.g. <b>section_xz</b> = <i>0</i>, <i>12</i>,
1856<i>27</i>),
1857then the respective data are successively written to file. The output
1858order follows the order given by <b>section_xz</b>.</font></span></td>
1859</tr> <tr> <td style="vertical-align: top;"><p><a name="section_yz"></a><b>section_yz</b></p>
1860</td> <td style="vertical-align: top;">I(100)<br>
1861</td> <td style="vertical-align: top;"><span style="font-style: italic;">no section</span></td>
1862<td style="vertical-align: top;"> <p lang="en-GB"><font face="Thorndale">Position of&nbsp;cross section(s)
1863for&nbsp;output of 2d (yz) vertical cross sections (grid point
1864index i).&nbsp; </font> </p> <span lang="en-GB"><font face="Thorndale">If output of
1865vertical yz cross sections is selected (see </font></span><a href="chapter_4.2.html#data_output"><span lang="en-GB"><font face="Thorndale">data_output</font></span></a><span lang="en-GB"><font face="Thorndale">),
1866this parameter can be used to define the position(s) of the cross
1867section(s). Up to 100 positions of cross sections can be selected by
1868assigning <b>section_yz</b> the corresponding horizontal
1869grid point
1870index/indices i of the requested cross section(s). The exact position
1871(in x-direction) of the cross section is given by i*</font></span><a href="chapter_4.1.html#dx"><span lang="en-GB"><font face="Thorndale">dx</font></span></a> <span lang="en-GB"><font face="Thorndale">or (i-0.5)*</font></span><a href="chapter_4.1.html#dx"><span lang="en-GB"><font face="Thorndale">dx</font></span></a><span lang="en-GB"><font face="Thorndale">, depending
1872on which grid the output quantity is defined.&nbsp;</font></span><span lang="en-GB"><font face="Thorndale">However, in
1873the&nbsp;NetCDF output file </font></span><span lang="en-GB"><font face="Thorndale">(if the
1874default NetCDF output is switched on; see <a href="chapter_4.2.html#data_output_format">data_output_format</a>)
1875no distinction is made between the quantities and i*<span style="font-weight: bold;">dx</span> is used for all
1876positions.<br><br></font></span><span lang="en-GB"><font face="Thorndale">Assigning <span style="font-weight: bold;">section_yz</span> = <span style="font-style: italic;">-1</span>
1877creates the output of vertical cross sections averaged along x. In the
1878NetCDF output file these (averaged) cross sections are given the
1879x-coordinate <span style="font-style: italic;">-1.0</span>.</font></span><br><span lang="en-GB"></span><span lang="en-GB"><font face="Thorndale"> <br></font></span><span lang="en-GB"><font face="Thorndale">In case of <span style="font-weight: bold;">data_output_format</span> =
1880<span style="font-style: italic;">'iso2d'</span> and
1881</font></span><span lang="en-GB"><font face="Thorndale">if several cross sections are
1882selected (e.g. <b>section_yz</b> = <span style="font-style: italic;">3</span>, <span style="font-style: italic;">27</span>, 19), then the
1883respective data are successively written to file. The output order
1884follows the order given by <b>section_yz</b>.</font></span></td>
1885</tr> <tr> <td style="vertical-align: top;"><a name="skip_time_data_output"></a><span style="font-weight: bold;">skip_time_data_output</span><br>
1886</td> <td style="vertical-align: top;">R<br> </td>
1887<td style="vertical-align: top;"><span style="font-style: italic;">0.0</span><br> </td>
1888<td style="vertical-align: top;">No data output before
1889this interval has passed (in s).<br><br>This
1890parameter causes that data output activities are starting not before
1891this interval
1892(counting from the beginning of the simulation, t=0) has passed. By
1893default, this
1894applies for output of instantaneous 3d volume data, cross section data,
1895spectra and vertical profile data as well as for temporally averaged 2d
1896and 3d data. Individual intervals can be assigned using parameters <a href="#skip_time_do3d">skip_time_do3d</a>, <a href="#skip_time_do2d_xy">skip_time_do2d_xy</a>, <a href="#skip_time_do2d_xz">skip_time_do2d_xz</a>, <a href="#skip_time_do2d_yz">skip_time_do2d_yz</a>, <a href="#skip_time_dosp">skip_time_dosp</a>,&nbsp;<a href="#skip_time_dopr">skip_time_dopr</a>, and <a href="#skip_time_data_output_av">skip_time_data_output_av</a>.<br><br><span style="font-weight: bold;">Example:</span><br>If
1897the user has set <a href="#dt_data_output">dt_data_output</a>
1898= <span style="font-style: italic;">3600.0</span>
1899and <span style="font-weight: bold;">skip_time_data_output</span>
1900= <span style="font-style: italic;">1800.0</span>,
1901then the first output will be done at t = 5400 s.<br> </td>
1902</tr> <tr><td style="vertical-align: top;"><a name="skip_time_data_output_av"></a><span style="font-weight: bold;">skip_time_data_output_av</span></td><td style="vertical-align: top;">R</td><td style="vertical-align: top;"><span style="font-style: italic;">value of <a href="#skip_time_data_output">skip_time_<br>data_output</a></span></td><td style="vertical-align: top;">No output of temporally
1903averaged 2d/3d data before this interval has passed (in s).<br><br>This
1904parameter causes that data output activities are starting not before
1905this interval
1906(counting from the beginning of the simulation, t=0) has passed. <br><br><span style="font-weight: bold;">Example:</span><br>If
1907the user has set <a href="#dt_data_output_av">dt_data_output_av</a>
1908= <span style="font-style: italic;">3600.0</span>
1909and <span style="font-weight: bold;">skip_time_data_output_av</span>
1910= <span style="font-style: italic;">1800.0</span>,
1911then the first output will be done at t = 5400 s.</td></tr><tr>
1912<td style="vertical-align: top;"><a name="skip_time_dopr"></a><span style="font-weight: bold;">skip_time_dopr</span><br>
1913</td> <td style="vertical-align: top;">R<br> </td>
1914<td style="vertical-align: top;"><span style="font-style: italic;">value of <a href="chapter_4.2.html#skip_time_data_output">skip_time_<br>data_output</a></span>
1915</td> <td style="vertical-align: top;">No output of
1916vertical profile data before this interval has passed (in s).<br><br>This
1917parameter causes that data output activities are starting not before
1918this interval
1919(counting from the beginning of the simulation, t=0) has passed. <br><br><span style="font-weight: bold;">Example:</span><br>If
1920the user has set <a href="#dt_dopr">dt_dopr</a> = <span style="font-style: italic;">3600.0</span> and <span style="font-weight: bold;">skip_time_dopr</span> = <span style="font-style: italic;">1800.0</span>, then the
1921first output will be done at t = 5400 s. </td> </tr> <tr>
1922<td style="vertical-align: top;"><a name="skip_time_do2d_xy"></a><span style="font-weight: bold;">skip_time_do2d_xy</span><br>
1923</td> <td style="vertical-align: top;">R<br> </td>
1924<td style="vertical-align: top;"><span style="font-style: italic;">value of <a href="chapter_4.2.html#skip_time_data_output">skip_time_<br>data_output</a></span>
1925</td> <td style="vertical-align: top;">No output of
1926instantaneous horizontal cross section data before this interval has
1927passed (in s).<br><br>This
1928parameter causes that data output activities are starting not before
1929this interval
1930(counting from the beginning of the simulation, t=0) has passed. <br><br><span style="font-weight: bold;">Example:</span><br>If
1931the user has set <a href="#dt_do2d_xy">dt_do2d_xy</a>
1932= <span style="font-style: italic;">3600.0</span>
1933and <span style="font-weight: bold;">skip_time_do2d_xy</span>
1934= <span style="font-style: italic;">1800.0</span>,
1935then the first output will be done at t = 5400 s. </td> </tr>
1936<tr> <td style="vertical-align: top;"><a name="skip_time_do2d_xz"></a><span style="font-weight: bold;">skip_time_do2d_xz</span><br>
1937</td> <td style="vertical-align: top;">R<br> </td>
1938<td style="vertical-align: top;"><span style="font-style: italic;">value of <a href="chapter_4.2.html#skip_time_data_output">skip_time_<br>data_output</a></span>
1939</td> <td style="vertical-align: top;">No output of
1940instantaneous vertical (xz) cross section data before this interval has
1941passed (in s).<br><br>This
1942parameter causes that data output activities are starting not before
1943this interval
1944(counting from the beginning of the simulation, t=0) has passed. <br><br><span style="font-weight: bold;">Example:</span><br>If
1945the user has set <a href="#dt_do2d_xz">dt_do2d_xz</a>
1946= <span style="font-style: italic;">3600.0</span>
1947and <span style="font-weight: bold;">skip_time_do2d_xz</span>
1948= <span style="font-style: italic;">1800.0</span>,
1949then the first output will be done at t = 5400 s. </td> </tr>
1950<tr> <td style="vertical-align: top;"><a name="skip_time_do2d_yz"></a><span style="font-weight: bold;">skip_time_do2d_yz</span><br>
1951</td> <td style="vertical-align: top;">R<br> </td>
1952<td style="vertical-align: top;"><span style="font-style: italic;">value of <a href="chapter_4.2.html#skip_time_data_output">skip_time_<br>data_output</a></span>
1953</td> <td style="vertical-align: top;">No output of
1954instantaneous vertical (yz) cross section data before this interval has
1955passed (in s).<br><br>This
1956parameter causes that data output activities are starting not before
1957this interval
1958(counting from the beginning of the simulation, t=0) has passed. <br><br><span style="font-weight: bold;">Example:</span><br>If
1959the user has set <a href="#dt_do2d_yz">dt_do2d_yz</a>
1960= <span style="font-style: italic;">3600.0</span>
1961and <span style="font-weight: bold;">skip_time_do2d_yz</span>
1962= <span style="font-style: italic;">1800.0</span>,
1963then the first output will be done at t = 5400 s. </td> </tr>
1964<tr> <td style="vertical-align: top;"><a name="skip_time_do3d"></a><span style="font-weight: bold;">skip_time_do3d</span><br>
1965</td> <td style="vertical-align: top;">R<br> </td>
1966<td style="vertical-align: top;"><span style="font-style: italic;">value of <a href="chapter_4.2.html#skip_time_data_output">skip_time_<br>data_output</a></span>
1967</td> <td style="vertical-align: top;">No output of
1968instantaneous 3d volume data before this interval has passed (in s).<br><br>This
1969parameter causes that data output activities are starting not before
1970this interval
1971(counting from the beginning of the simulation, t=0) has passed. <br><br><span style="font-weight: bold;">Example:</span><br>If
1972the user has set <a href="#dt_do3d">dt_do3d</a> = <span style="font-style: italic;">3600.0</span> and <span style="font-weight: bold;">skip_time_do3d</span> = <span style="font-style: italic;">1800.0</span>, then the
1973first output will be done at t = 5400 s. </td> </tr>
1974<tr> <td style="vertical-align: top;"> <p><a name="termination_time_needed"></a><b>termination_time</b>
1975<br> <b>_needed</b></p> </td> <td style="vertical-align: top;">R<br> </td> <td style="vertical-align: top;"><span style="font-style: italic;">35.0</span><br> </td>
1976<td style="vertical-align: top;"> <p>CPU time
1977needed for terminal actions at the end of a run in
1978batch mode (in s).<br> </p> <p>If the environment
1979variable <b>write_binary </b>is
1980set <i>true</i> (see <a href="chapter_3.3.html">chapter
19813.3</a>), PALM checks the remaining CPU time of the job after
1982each
1983timestep. Time integration must not consume the CPU time completely,
1984since several actions still have to be carried out after time
1985integration has finished (e.g. writing of binary data for the restart
1986run, carrying out output commands, copying of local files to their
1987permanent destinations, etc.) which also takes some time. The maximum
1988possible time needed for these activities plus a reserve is to be given
1989with the parameter <b>termination_time_needed</b>. Among
1990other things,
1991it depends on
1992the number of grid points used. If its value is selected too small,
1993then the
1994respective job will be prematurely aborted by the queuing system, which
1995may result in a data loss and will possibly interrupt the job chain.<br>
1996</p> <p>An abort happens in any way, if the environment
1997variable <span style="font-weight: bold;">write_binary</span>
1998is not set to <span style="font-style: italic;">true</span>
1999and if moreover the job has
2000been assigned an insufficient CPU time by <b>mrun</b>
2001option <tt><tt>-t</tt></tt>. <i><br>
2002</i> </p> <p><span style="font-weight: bold;">Note:</span><br>
2003On the IBM computers of the HLRN the time used by the job <span style="font-weight: bold;">before</span> the start of
2004PALM
2005have also to be accounted for (e.g. for
2006compilation and copying of input files).</p> </td> </tr>
2007<tr> <td style="vertical-align: top;"> <p><a name="use_prior_plot1d_parameters"></a><b>use_prior_plot1d</b>
2008<br> <b>_parameters</b></p> </td> <td style="vertical-align: top;">L</td> <td style="vertical-align: top;"><i>.F.</i></td>
2009<td style="vertical-align: top;"> <p>Additional
2010plot of vertical profile data with <span style="font-weight: bold;">profil</span>
2011from preceding runs of the
2012job chain.&nbsp; </p> <p>This parameter only applies
2013for &nbsp;<a href="chapter_4.2.html#data_output_format">data_output_format</a>
2014= <span style="font-style: italic;">'profil'</span>.</p><p>By
2015default, plots of horizontally averaged vertical profiles
2016(see <a href="#data_output_pr">data_output_pr</a>)
2017only contain profiles of data produced by the model
2018run. If profiles of prior times (i.e. data of preceding jobs of a
2019job chain) shall be plotted additionally (e.g. for comparison
2020purposes), <b>use_prior_plot1d_parameters</b> = <i>.T</i>.
2021must be
2022set.<br> </p> <p>For further explanation see <a href="chapter_4.5.2.html">chapter
20234.5.2</a>.</p> </td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="z_max_do1d"></a><b>z_max_do1d</b></p>
2024</td> <td style="vertical-align: top;">R</td>
2025<td style="vertical-align: top;"><i>zu(nzt+1) (model
2026top)</i></td> <td style="vertical-align: top;">
2027<p>Height level up to which horizontally averaged profiles are to
2028be
2029plotted with <span style="font-weight: bold;">profil</span>
2030(in
2031m).&nbsp; </p> <p>This parameter only applies for
2032&nbsp;<a href="chapter_4.2.html#data_output_format">data_output_format</a>
2033= <span style="font-style: italic;">'profil'</span>.</p><p>It
2034affects plots of horizontally averaged profiles
2035(<a href="#data_output_pr">data_output_pr</a>)
2036when plotted with the plot software <span style="font-weight: bold;">profil</span>.
2037By default, profiles are plotted up to the top boundary. The height
2038level up to which profiles are plotted can be decreased by assigning <span style="font-weight: bold;">z_max_do1d</span> a smaller
2039value.
2040Nevertheless, <span style="font-weight: bold;">all</span>
2041vertical
2042grid points (0 &lt;= k &lt;= nz+1) are still output to file <a href="chapter_3.4.html#PLOT1D_DATA">PLOT1D_DATA</a>.</p>
2043<p>If a normalization for the vertical axis was selected (see <a href="#cross_normalized_y">cross_normalized_y</a>), <b>z_max_do1d</b>
2044has no effect. Instead, <a href="#z_max_do1d_normalized">z_max_do1d_normalized</a>
2045must be used.</p> </td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="z_max_do1d_normalized"></a><b>z_max_do1d</b>
2046<br> <b>_normalized</b></p> </td> <td style="vertical-align: top;">R</td> <td style="vertical-align: top;"><i>determined by plot</i>
2047<br> <i>data</i> <br> </td> <td style="vertical-align: top;"> <p>Normalized height
2048level up to which horizontally averaged
2049profiles are to be plotted with <span style="font-weight: bold;">profil</span>.&nbsp;
2050</p> <p>This parameter only applies for &nbsp;<a href="chapter_4.2.html#data_output_format">data_output_format</a>
2051= <span style="font-style: italic;">'profil'</span>.</p><p>It
2052affects plots of horizontally averaged profiles
2053(<a href="#data_output_pr">data_output_pr</a>)
2054when plotted with the plot software <span style="font-weight: bold;">profil</span>,
2055if a normalization for the vertical axis is selected
2056(see <a href="#cross_normalized_y">cross_normalized_y</a>).
2057If e.g. the boundary layer height is used for normalization, then <b>z_max_do1d_normalized</b>
2058= <i>1.5</i> means that all profiles up to the height
2059level of z =
20601.5* z<sub>i </sub>are plotted.</p> </td> </tr>
2061<tr> <td style="vertical-align: top;"> <p><a name="z_max_do2d"></a><b>z_max_do2d</b></p>
2062</td> <td style="vertical-align: top;">R<br> </td>
2063<td style="vertical-align: top;"><span style="font-style: italic;">zu(nz)</span><br> </td>
2064<td style="vertical-align: top;"> <p>Height level
2065up to which 2d cross sections are to be plotted
2066with <span style="font-weight: bold;">iso2d</span>
2067(in m).&nbsp; </p> <p>This parameter only applies for
2068&nbsp;<a href="#data_output_format">data_output_format</a>
2069= <span style="font-style: italic;">'iso2d'</span>.</p><p>It
2070affects plots of&nbsp; 2d vertical cross
2071sections (<a href="#data_output">data_output</a>)
2072when plotted with <span style="font-weight: bold;">iso2d</span>.
2073By
2074default, vertical sections are plotted up to the top boundary. <span style="font-weight: bold;"></span>In contrast, with <b>z_max_do2d
2075</b>the
2076visualization within
2077the plot can be limited to a certain height level (0 &lt;= z
2078&lt;= <b>z_max_do2d</b>).
2079Nevertheless, <span style="font-weight: bold;">all</span>
2080grid points
2081of the complete cross section are still output to the local files <a href="chapter_3.4.html#PLOT2D_XZ">PLOT2D_XZ</a>
2082or <a href="chapter_3.4.html#PLOT2D_YZ">PLOT2D_YZ</a>.
2083The level up to which the section is visualized can later be changed by
2084manually editing the
2085file <a href="chapter_3.4.html#PLOT2D_XZ_GLOBAL">PLOT2D_XZ_GLOBAL</a>
2086or <a href="chapter_3.4.html#PLOT2D_YZ_GLOBAL">PLOT2D_YZ_GLOBAL</a>
2087(the respective <span style="font-weight: bold;">iso2d</span>-parameter
2088is <a href="http://www.muk.uni-hannover.de/institut/software/iso2d_beschreibung.html#YRIGHT">yright</a>).</p>
2089</td> </tr> </tbody></table><br>
2090<br><h3 style="line-height: 100%;"><a name="Paketparameter"></a>Package
2091parameters: </h3>
2092Package (<span style="font-weight: bold;">mrun</span>
2093option -p): <span style="font-weight: bold;"><a name="particles_package"></a>particles</span>&nbsp;&nbsp;&nbsp;&nbsp;
2094NAMELIST group name: <span style="font-weight: bold;">particles_par<br>
2095</span><table style="text-align: left; width: 100%;" border="1" cellpadding="2" cellspacing="2"> <tbody><tr>
2096<td style="vertical-align: top;"><font size="4"><b>Parameter
2097name</b></font></td>
2098<td style="vertical-align: top;"><font size="4"><b>Type</b></font></td>
2099<td style="vertical-align: top;"> <p><b><font size="4">Default</font></b> <br> <b><font size="4">value</font></b></p> </td>
2100<td style="vertical-align: top;"> <p><font size="4"><b>Explanation</b></font></p>
2101</td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="dt_prel"></a><b>dt_prel</b></p>
2102</td> <td style="vertical-align: top;">R</td>
2103<td style="vertical-align: top;"><i>9999999.9</i></td>
2104<td style="vertical-align: top;"> <p><font face="Thorndale, serif"><span lang="en-GB">Temporal
2105interval at
2106which particles are to be released <span lang="en-GB">from
2107a particle
2108source </span>(</span></font>in <font face="Thorndale, serif"><span lang="en-GB">s).</span>&nbsp;
2109</font> </p> <p><span lang="en-GB"><font face="Thorndale, serif">By default
2110particles are released only at the beginning of a simulation
2111(t_init=0). The time of the first release (t_init) can be changed with
2112package parameter </font></span><span lang="en-GB"></span><font><a href="#particle_advection_start"><font face="Thorndale, serif">particle_advection_start</font></a>.
2113</font><span lang="en-GB"><font face="Thorndale, serif">The time of the last release can be
2114set with the package parameter <a href="#end_time_prel">end_time_prel</a>.
2115If <span style="font-weight: bold;">dt_prel</span>
2116has been set, additional
2117releases will be at t = t_init+<span style="font-weight: bold;">dt_prel</span>,
2118t_init+2*<span style="font-weight: bold;">dt_prel</span>,
2119t_init+3*<span style="font-weight: bold;">dt_prel</span>,
2120etc.. Actual release times
2121may slightly deviate from thesel values (</font></span><span lang="en-GB"><font face="Thorndale, serif">see
2122e.g. </font></span><a href="#dt_dopr"><span lang="en-GB"><font face="Thorndale, serif">dt_dopr</font></span></a><span lang="en-GB"><font face="Thorndale, serif">).</font></span></p>
2123<p><span lang="en-GB"><font face="Thorndale, serif"> The domain
2124of the particle <span lang="en-GB"><font face="Thorndale, serif">source </font></span>as
2125well as the distance of&nbsp; released particles
2126within this source </font></span><span lang="en-GB"><font face="Thorndale, serif">are determined via package
2127parameters </font></span><a href="#pst"><span lang="en-GB"><font face="Thorndale, serif">pst</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="#psl"><span lang="en-GB"><font face="Thorndale, serif">psl</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="#psr"><span lang="en-GB"><font face="Thorndale, serif">psr</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="#pss"><span lang="en-GB"><font face="Thorndale, serif">pss</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="#psn"><span lang="en-GB"><font face="Thorndale, serif">psn</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="#psb"><span lang="en-GB"><font face="Thorndale, serif">psb</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="#pdx"><span lang="en-GB"><font face="Thorndale, serif">pdx</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="#pdy"><span lang="en-GB"><font face="Thorndale, serif">pdy</font></span></a>
2128<span lang="en-GB"><font face="Thorndale, serif">and
2129</font></span><a href="#pdz"><span lang="en-GB"><font face="Thorndale, serif">pdz</font></span></a><span lang="en-GB"><font face="Thorndale, serif">.</font></span><span lang="en-GB"><font face="Thorndale, serif"> By
2130default, one particle is released at all points defined by these
2131parameters. The package parameter <a href="#particles_per_point">particles_per_point</a>
2132can be used to start more than one particle per point.<br>
2133</font></span></p> <p><span lang="en-GB"><font face="Thorndale, serif">Up to 10
2134different groups of particles can be released at the same time (see </font></span><a href="chapter_4.2.html#number_of_particle_groups"><span lang="en-GB"><font face="Thorndale, serif">number_of_particle_groups</font></span></a><span lang="en-GB"><font face="Thorndale, serif">)
2135where each group may have a different source. All particles belonging
2136to one group have the same density ratio and the same radius. All other
2137particle features (e.g. location of the source) are
2138identical for all groups of particles.</font></span></p>Subgrid
2139scale velocities can (optionally) be included for calculating the
2140particle advection, using the method of Weil et al. (2004, JAS, 61,
21412877-2887). This method is switched on by the package
2142parameter <a href="#use_sgs_for_particles">use_sgs_for_particles</a>.
2143This also forces the Euler/upstream method to be used for time
2144advancement of the TKE (see initialization parameter <a href="chapter_4.1.html#use_upstream_for_tke">use_upstream_for_tke</a>).
2145The minimum timestep during the sub-timesteps is controlled by package
2146parameter <a href="#dt_min_part">dt_min_part</a>. <p><span lang="en-GB"><font face="Thorndale, serif">By
2147default, particles are weightless and transported passively with the
2148resolved scale flow. Particles can be given a mass and thus an inertia
2149by assigning the
2150package parameter </font></span><a href="#density_ratio"><span lang="en-GB"><font face="Thorndale, serif">density_ratio</font></span></a><span lang="en-GB"><font face="Thorndale, serif"> a
2151non-zero value (it
2152defines the ratio of the density of the fluid and the density of the
2153particles). In these cases their </font></span><a href="#radius"><span lang="en-GB"><font face="Thorndale, serif">radius</font></span></a><span lang="en-GB"></span><span lang="en-GB"><font face="Thorndale, serif">
2154must also be defined, which affects their flow resistance. </font></span><a href="#diameter"><span lang="en-GB"></span></a><span lang="en-GB"></span><span lang="en-GB"><font face="Thorndale, serif"> </font></span> </p>
2155<p><span lang="en-GB"><font face="Thorndale, serif">Boundary
2156conditions for the particle transport can be defined with package
2157parameters </font></span><a href="#bc_par_t"><span lang="en-GB"><font face="Thorndale, serif">bc_par_t</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="#bc_par_lr"><span lang="en-GB"><font face="Thorndale, serif">bc_par_lr</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="bc_par_ns"><span lang="en-GB"><font face="Thorndale, serif">bc_par_ns</font></span></a>
2158<span lang="en-GB"><font face="Thorndale, serif">and
2159</font></span><a href="#bc_par_b"><span lang="en-GB"><font face="Thorndale, serif">bc_par_b</font></span></a><span lang="en-GB"><font face="Thorndale, serif">.</font></span></p><span lang="en-GB"><font face="Thorndale, serif">Timeseries
2160of particle quantities in NetCDF format can be output to local file <a href="chapter_3.4.html#DATA_1D_PTS_NETCDF">DATA_1D_PTS_NETCDF</a>
2161by using package parameter <a href="#dt_dopts">dt_dopts</a>.<br></font></span><p>For
2162analysis, additional output of
2163particle
2164information in equidistant temporal intervals can be carried out using <a href="#dt_write_particle_data">dt_write_particle_data</a>
2165(file <a href="chapter_3.4.html#PARTICLE_DATA">PARTICLE_DATA</a>).<br>
2166</p> <p><span style="font-family: thorndale,serif;">Statistical
2167informations</span> (e.g. the total number of particles used, the
2168number of particles exchanged between the PEs, etc.) are output to the
2169local file <a href="chapter_3.4.html#PARTICLE_DATA">PARTICLE_INFOS</a>,
2170if switched on by the parameter <a href="#write_particle_statistics">write_particle_statistics</a>.
2171<br> </p> <p><span lang="en-GB"><font face="Thorndale, serif">If a job
2172chain is to be carried out, particle
2173informations </font></span><span lang="en-GB"><font face="Thorndale, serif">for the restart run (e.g. current
2174location of
2175all
2176particles at the end of the
2177run) is output to
2178the local file</font></span> <font><a href="chapter_4.2.html#dt_dvrp"><span lang="en-GB"></span></a></font><a href="chapter_3.4.html#PARTICLE_RESTART_DATA_OUT">PARTICLE_RESTART_DATA_OUT</a><font><a href="chapter_4.2.html#dt_dvrp"><span lang="en-GB"></span></a></font>,
2179<span lang="en-GB"><font face="Thorndale, serif">which
2180must be saved at the
2181end of the run <tt><span lang="en-GB"></span></tt>and
2182given as an
2183input file to the restart run
2184under local file name</font></span> <a href="chapter_3.4.html#PARTICLE_RESTART_DATA_IN">PARTICLE_RESTART_DATA_IN</a>
2185u<span lang="en-GB"><font face="Thorndale, serif">sing
2186respective file
2187connection statements in the <span style="font-weight: bold;">mrun</span>
2188configuration file. </font></span> <span lang="en-GB"></span></p><p><span lang="en-GB"></span><span lang="en-GB"><font face="Thorndale, serif">The output of
2189particles for visualization with the graphic software <span style="font-weight: bold;">dvrp</span> is steered by
2190the package
2191parameter </font></span><a href="chapter_4.2.html#dt_dvrp"><span lang="en-GB"><font face="Thorndale, serif">dt_dvrp</font></span></a><font face="Thorndale, serif"><span lang="en-GB">.
2192For visualization
2193purposes particles can be given a
2194diameter by the parameter <a href="chapter_4.2.html#dvrp_psize">dvrp_psize</a>
2195(this diameter only affects the visualization). All particles have the
2196same size. Alternatively, particles can be given an individual size and
2197a </span>color <span lang="en-GB">by modifying the
2198user-interface (subroutine</span></font> <span style="font-family: monospace;">user_init_particles</span>)<span lang="en-GB"><font face="Thorndale, serif">.
2199Particles can pull a
2200&ldquo;tail&rdquo; behind themselves to improve their
2201visualization.
2202This is steered via the parameter&nbsp;<a href="chapter_4.2.html#use_particle_tails">use_particle_tails</a>.</font></span><a href="chapter_4.2.html#maximum_number_of_tailpoints"><span lang="en-GB"></span></a></p> <span lang="en-GB"></span><p><b>So far, the
2203particle transport realized in PALM does only
2204work
2205duly in case of a constant vertical grid spacing!</b></p> </td>
2206</tr> <tr> <td style="vertical-align: top;"><p><a name="bc_par_b"></a><b>bc_par_b</b></p>
2207</td> <td style="vertical-align: top;">C*15</td>
2208<td style="vertical-align: top;"><i>&acute;reflect&acute;</i></td>
2209<td style="vertical-align: top;"> <p>Bottom
2210boundary condition for particle transport. </p> <p>By
2211default, particles are reflected at the bottom boundary.
2212Alternatively, a particle absorption can set by <b>bc_par_b</b>
2213= <i>&acute;absorb&acute;</i>.</p> </td>
2214</tr> <tr> <td style="vertical-align: top;"><p><a name="bc_par_lr"></a><b>bc_par_lr</b></p>
2215</td> <td style="vertical-align: top;">C*15</td>
2216<td style="vertical-align: top;"><i>&acute;cyclic&acute;</i></td>
2217<td style="vertical-align: top;"> <p>Lateral
2218boundary condition (x-direction) for particle
2219transport. </p> <p>By default, cyclic boundary conditions
2220are used along x.
2221Alternatively, reflection (<b>bc_par_lr</b>
2222= <i>&acute;reflect&acute;</i>) or absorption (<b>bc_par_lr</b>
2223= <i>&acute;absorb&acute;</i>)
2224can be set. <br> </p> <p>This lateral boundary
2225conditions should correspond to the
2226lateral boundary condition used for the flow (see <a href="chapter_4.1.html#bc_lr">bc_lr</a>).</p> </td>
2227</tr> <tr> <td style="vertical-align: top;"><p><a name="bc_par_ns"></a><b>bc_par_ns</b></p>
2228</td> <td style="vertical-align: top;">C*15</td>
2229<td style="vertical-align: top;"><i>&acute;cyclic&acute;</i></td>
2230<td style="vertical-align: top;"> <p>Lateral
2231boundary condition (y-direction) for particle
2232transport. </p> <p>By default, cyclic boundary conditions
2233are used along y.
2234Alternatively, reflection (<b>bc_par_ns</b>
2235= <i>&acute;reflect&acute;</i>) or absorption (<b>bc_par_ns</b>
2236= <i>&acute;absorb&acute;</i>)
2237can be set.<br> </p>
2238This lateral boundary conditions should correspond to the lateral
2239boundary condition used for the flow (see <a href="chapter_4.1.html#bc_ns">bc_ns</a>).</td> </tr>
2240<tr> <td style="vertical-align: top;"> <p><a name="bc_par_t"></a><b>bc_par_t</b></p>
2241</td> <td style="vertical-align: top;">C*15</td>
2242<td style="vertical-align: top;"><i>&acute;absorb&acute;</i></td>
2243<td style="vertical-align: top;"> <p>Top boundary
2244condition for particle transport. </p> <p>By default,
2245particles are absorbed at the top boundary.
2246Alternatively, a reflection condition can be set by <b>bc_par_t</b>
2247= <i>&acute;reflect&acute;</i>.</p> </td>
2248</tr> <tr> <td style="vertical-align: top;"><p><a name="density_ratio"></a><b>density_ratio</b></p>
2249</td> <td style="vertical-align: top;">R (10)</td>
2250<td style="vertical-align: top;"> <p><i>0.0, 9</i>
2251*<br> <i>9999999.9</i></p> </td> <td style="vertical-align: top;"> <p>Ratio of the density
2252of the fluid and the density of the
2253particles. </p> <p>With the default value<i> </i>the
2254particles are weightless and transported passively with the resolved
2255scale flow.
2256In case of <span style="font-weight: bold;">density_ratio</span>
2257/=
22580.0 particles have a mass and hence inertia so that their velocity
2259deviates more or less from the velocity of the surrounding flow.
2260Particle velocity is calculated analytically and depends on (besides
2261the density ratio and the current velocity difference between particles
2262and surrounding fluid) the
2263particle radius which is determined via <a href="#radius">radius</a>
2264as well as on the molecular viscosity (assumed as 1.461E-5 m<sup>2</sup>/s).
2265</p> <p>If <b>density_ratio</b> = <i>1.0</i>,
2266the particle density
2267corresponds to the density of the surrounding fluid and the particles
2268do not feel any buoyancy. Otherwise, particles will be accelerated
2269upwards (<b>density_ratio</b> &gt; <i>1.0</i>)
2270or downwards (<b>density_ratio</b> &lt; <i>1.0</i>).<br>
2271</p> <p>With several groups of particles (see <a href="chapter_4.2.html#number_of_particle_groups">number_of_particle_groups</a>),
2272each group can be assigned a different value. If the number of values
2273given for <span style="font-weight: bold;">density_ratio</span>
2274is less than the number of
2275groups defined by <span style="font-weight: bold;">number_of_particle_groups</span>,
2276then the last assigned value is used for all remaining groups. This
2277means that by default the particle density ratio for all groups will be
2278<span style="font-style: italic;">0.0</span>.</p>
2279</td> </tr> <tr><td align="left" valign="top"><a name="dt_dopts"></a><span style="font-weight: bold;">dt_dopts</span></td><td align="left" valign="top">R</td><td align="left" valign="top"><i>value of &nbsp;<a href="chapter_4.2.html#dt_data_output">dt_data_<br>output</a></i></td><td align="left" valign="top"><p lang="en-GB"><font face="Thorndale"><font face="Thorndale, serif">Temporal
2280interval</font> at which time series data of particle quantities
2281shall be output (</font>in <font face="Thorndale">s).&nbsp;</font></p>
2282<span lang="en-GB"><font face="Thorndale">If
2283particle advection is switched on (see</font></span><font><span style="font-family: thorndale;"> <a href="#dt_prel">dt_prel</a>)
2284this parameter can be used to assign
2285th</span></font><span lang="en-GB"><font face="Thorndale">e temporal
2286interval at which time series of particle quantities shall be output.
2287Output is written in NetCDF format on local file <a href="chapter_3.4.html#DATA_1D_PTS_NETCDF">DATA_1D_PTS_NETCDF</a>.<br><br>The
2288following list gives a short description of the&nbsp;quantities
2289available. Most quantities are averages over all particles. The
2290quantity name given in the first column is identical to the respective
2291name of the variable on the NetCDF file (see section <a href="chapter_4.5.1.html">4.5.1</a> for a general
2292description of the NetCDF files).<br><br>In case of using
2293more than one particle group (see <a href="#number_of_particle_groups">number_of_particle_groups</a>),
2294seperate time series are output for each of the groups. The long names
2295of the variables in the NetCDF file containing the respective
2296timeseries all end with the string</font><span style="font-style: italic; font-family: monospace;">' PG ##'</span><font face="Thorndale">, where ## is the number of the particle
2297group (<span style="font-style: italic;">01</span>, <span style="font-style: italic;">02</span>, etc.). <br>&nbsp;</font></span><table style="text-align: left; width: 631px; height: 652px;" border="1" cellpadding="2" cellspacing="2"><tbody><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">tnpt</span></td><td align="undefined" valign="undefined">total number of
2298particles</td></tr><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">x_</span></td><td align="undefined" valign="undefined">particle
2299x-coordinate&nbsp;with respect to the particle origin (in m)</td></tr><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">y_</span></td><td align="undefined" valign="undefined">particle
2300y-coordinate&nbsp;with respect to the particle origin (in m)</td></tr><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">z_</span></td><td align="undefined" valign="undefined">particle
2301z-coordinate&nbsp;with respect to the particle origin (in m)</td></tr><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">z_abs</span></td><td align="undefined" valign="undefined">absolute
2302particle z-coordinate (in m)</td></tr><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">u</span></td><td align="undefined" valign="undefined">u particle
2303velocity component (in m/s)</td></tr><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">v</span></td><td align="undefined" valign="undefined">v particle
2304velocity component (in m/s)</td></tr><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">w</span></td><td align="undefined" valign="undefined">w particle
2305velocity component (in m/s)</td></tr><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">u"</span></td><td align="undefined" valign="undefined">subgrid-scale u
2306particle velocity component (in m/s)</td></tr><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">v"</span></td><td align="undefined" valign="undefined">subgrid-scale v
2307particle velocity component (in m/s)</td></tr><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">w"</span></td><td align="undefined" valign="undefined">subgrid-scale w
2308particle velocity component (in m/s)</td></tr><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">npt_up</span></td><td align="undefined" valign="undefined">total number of
2309upward moving particles</td></tr><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">w_up</span></td><td align="undefined" valign="undefined">vertical
2310velocity of the upward moving particles (in m/s)</td></tr><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">w_down</span></td><td align="undefined" valign="undefined">vertical
2311velocity of the downward moving particles (in m/s)</td></tr><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">npt_max</span></td><td align="undefined" valign="undefined">maximum number
2312of particles in a subdomain (=tnpt for non-parallel runs)</td></tr><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">npt_min</span></td><td align="undefined" valign="undefined">minimum number
2313of particles in a subdomain (=tnpt for non-parallel runs)</td></tr><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">x*2</span></td><td align="undefined" valign="undefined">variance of the
2314particle x-coordinate&nbsp;with respect to <span style="color: rgb(255, 0, 0);">x_ </span>(in m<sup>2</sup>)</td></tr><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">y*2</span></td><td align="undefined" valign="undefined">variance of the
2315particle y-coordinate&nbsp;with respect to <span style="color: rgb(255, 0, 0);">y_</span> (in m<sup>2</sup>)</td></tr><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">z*2</span></td><td align="undefined" valign="undefined">variance of the
2316particle z-coordinate&nbsp;with respect to <span style="color: rgb(255, 0, 0);">z_</span> (in m<sup>2</sup>)</td></tr><tr><td align="undefined" valign="undefined"><span style="color: rgb(255, 0, 0);">u*2</span></td><td align="undefined" valign="undefined">variance of the
2317u particle velocity component with respect to <span style="color: rgb(255, 0, 0);">u </span>(in m<sup>2</sup>/s<sup>2</sup>)</td></tr><tr><td align="undefined" valign="undefined">v*2</td><td align="undefined" valign="undefined">variance of the
2318v particle velocity component with respect to&nbsp;<span style="color: rgb(255, 0, 0);">v </span>(in m<sup>2</sup>/s<sup>2</sup>)</td></tr><tr><td align="undefined" valign="undefined">w*2</td><td align="undefined" valign="undefined">variance of the
2319w particle velocity component with respect to&nbsp;<span style="color: rgb(255, 0, 0);">w </span>(in m<sup>2</sup>/s<sup>2</sup>)</td></tr><tr><td align="undefined" valign="undefined">u"2</td><td align="undefined" valign="undefined">variance of the
2320subgrid-scale u particle velocity component with respect to <span style="color: rgb(255, 0, 0);">u" </span>(in m<sup>2</sup>/s<sup>2</sup>)</td></tr><tr><td align="undefined" valign="undefined">v"2</td><td align="undefined" valign="undefined">variance of the
2321subgrid-scale v particle velocity component with respect to <span style="color: rgb(255, 0, 0);">v" </span>(in m<sup>2</sup>/s<sup>2</sup>)</td></tr><tr><td align="undefined" valign="undefined">w"2</td><td align="undefined" valign="undefined">variance of the
2322subgrid-scale w particle velocity component with respect to <span style="color: rgb(255, 0, 0);">w" </span>(in m<sup>2</sup>/s<sup>2</sup>)</td></tr><tr><td align="undefined" valign="undefined">npt*2</td><td align="undefined" valign="undefined">variance of the
2323number of particles with respect to the average number of particles per
2324subdomain</td></tr></tbody></table><span lang="en-GB"></span><span lang="en-GB"></span></td></tr><tr><td align="left" valign="top"><a name="dt_min_part"></a><span style="font-weight: bold;">dt_min_part</span></td><td align="left" valign="top">R</td><td align="left" valign="top"><span style="font-style: italic;">0.0002</span></td><td align="left" valign="top">Minimum value for the
2325particle timestep when SGS velocities are used (in s).<br><br>For
2326a further explanation see package parameter <a href="#use_sgs_for_particles">use_sgs_for_particles</a>.</td></tr><tr>
2327<td style="vertical-align: top;"> <p><a name="dt_write_particle_data"></a><b>dt_write_particle_</b>
2328<b>data</b></p> </td> <td style="vertical-align: top;">R<br> </td> <td style="vertical-align: top;"><i>9999999.9</i></td>
2329<td style="vertical-align: top;"> <p>Temporal
2330interval for output of particle data (in s). </p> <p>T<span lang="en-GB"></span><a href="#pr1d"><span lang="en-GB"></span></a><span lang="en-GB"></span><span lang="en-GB"><font face="Thorndale">his
2331parameter can be used to
2332assign the temporal interval at which particle data shall be output.</font></span>
2333Data are output to
2334the local file <a href="chapter_3.4.html#PARTICLE_DATA">PARTICLE_DATA</a>.
2335<span style="font-family: mon;">See the file description
2336for more
2337details about its format</span>. </p> <p>By
2338default, no particle data are output.</p> </td> </tr>
2339<tr> <td style="vertical-align: top;"> <p><a name="dvrp_psize"></a><b>dvrp_psize</b></p>
2340</td> <td style="vertical-align: top;">R<br> </td>
2341<td style="vertical-align: top;">0.2 * dx<br> </td>
2342<td style="vertical-align: top;"> <p>Diameter that
2343the particles is given in visualizations with
2344the <span style="font-weight: bold;">dvrp</span>
2345software (in
2346m).&nbsp; </p> <p>In case that particles are
2347visualized with the <span style="font-weight: bold;">dvrp</span>
2348software (see <a href="chapter_4.5.7.html">chapter
23494.5.7</a>), their size can be set by parameter <b>dvrp_psize</b>.
2350All
2351particles are displayed with this same size.<br> </p> <p>Alternatively,
2352the particle diameters can be set with the
2353user-interface in routine <span style="font-family: monospace;">user_init_particles</span>
2354(at the beginning of the simulation) and/or can be redefined after each
2355timestep in routine <tt>user<font style="font-size: 11pt;" size="2">_particle_attributes</font></tt>
2356(both routines can be found in file <tt><font style="font-size: 11pt;" size="2">user_interface.f90</font></tt><font style="font-size: 11pt;" size="2">)</font>.&nbsp;</p>
2357<p><b>Note:</b> This parameter determines exclusively
2358the size
2359under which particles appear in the <span style="font-weight: bold;">dvrp</span>
2360visualization. The flow relevant particle radius is determined via the
2361particle package parameter <a href="#radius">radius</a>!</p>
2362</td> </tr> <tr><td align="left" valign="top"><a name="end_time_prel"></a><span style="font-weight: bold;">end_time_prel</span></td><td align="left" valign="top">R</td><td align="left" valign="top"><span style="font-style: italic;">9999999.9</span></td><td align="left" valign="top">Time of the last release of
2363particles (in s).<br><br>See also <a href="#particle_advection_start">particle_advection_start</a>.</td></tr><tr>
2364<td style="vertical-align: top;"><span style="font-weight: bold;"><a name="initial_weighting_factor"></a>initial_weighting_factor</span></td>
2365<td style="vertical-align: top;">R<br> </td> <td style="vertical-align: top;"><span style="font-style: italic;">1.0</span><br> </td>
2366<td style="vertical-align: top;">Factor to define the real
2367number of initial droplets in a grid box.<br> <br>
2368In case of explicitly simulating cloud droplets (see <a href="chapter_4.1.html#cloud_droplets">cloud_droplets</a>),
2369the real number of initial droplets in a grid box is equal to the
2370initial number of droplets in this box (defined by the particle source
2371parameters <span lang="en-GB"><font face="Thorndale, serif"> </font></span><a href="chapter_4.2.html#pst"><span lang="en-GB"><font face="Thorndale, serif">pst</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#psl"><span lang="en-GB"><font face="Thorndale, serif">psl</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#psr"><span lang="en-GB"><font face="Thorndale, serif">psr</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#pss"><span lang="en-GB"><font face="Thorndale, serif">pss</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#psn"><span lang="en-GB"><font face="Thorndale, serif">psn</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#psb"><span lang="en-GB"><font face="Thorndale, serif">psb</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#pdx"><span lang="en-GB"><font face="Thorndale, serif">pdx</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#pdy"><span lang="en-GB"><font face="Thorndale, serif">pdy</font></span></a>
2372<span lang="en-GB"><font face="Thorndale, serif">and
2373</font></span><a href="chapter_4.2.html#pdz"><span lang="en-GB"><font face="Thorndale, serif">pdz</font></span></a><span lang="en-GB"></span><span lang="en-GB"></span>)
2374times the <span style="font-weight: bold;">initial_weighting_factor</span>.</td>
2375</tr><tr> <td style="vertical-align: top;"> <p><a name="maximum_number_of_particles"></a><b>maximum_number_of_</b>
2376<br> <b>particles</b></p> </td> <td style="vertical-align: top;">I</td> <td style="vertical-align: top;"><i>1000</i></td>
2377<td style="vertical-align: top;"> <p>Maximum number
2378of particles (on a PE).&nbsp; </p> <p>This parameter
2379allows to set the number of particles for which
2380memory must be allocated at the beginning of the run.
2381If this memory becomes insufficient during the run, due to the
2382release of further particles (see <a href="#dt_prel">dt_prel</a>),
2383then more memory is automatically allocated.<br> </p>
2384For runs on several processors, <span style="font-weight: bold;">maximum_number_of_particles</span>
2385defines
2386the maximum number on each PE. This number must be larger than the
2387maximum number of particles initially released in a subdomain.</td>
2388</tr> <tr> <td style="vertical-align: top;"><p><a name="maximum_number_of_tailpoints"></a><b>maximum_number_of_</b>
2389<br> <b>tailpoints</b></p> </td> <td style="vertical-align: top;">I</td> <td style="vertical-align: top;"><i>100</i></td>
2390<td style="vertical-align: top;"> <p>Maximum number
2391of tailpoints that a particle tail can
2392have.&nbsp; </p> <p>&nbsp;<b>maximum_number_of_tailpoints</b>
2393sets the number of descrete points the tail consists of. A new point is
2394added to the particle tails after each time step. If the maximum number
2395of tail
2396points is reached after the corresponding number of timesteps, the
2397oldest respective tail points is deleted within the following
2398timestep.&nbsp; </p> <p>All particle tails have the
2399same number of points. The maximum
2400length of
2401these
2402tails is determined by the value of <b>maximum_number_of_tailpoints</b>
2403and by the minimum distance between each of the adjoining
2404tailpoints,&nbsp; which can be set by <a href="#minimum_tailpoint_distance">minimum_tailpoint_distance</a>.
2405Additionally, it can be determined that the temporal displacement
2406between the current position of the particle and the oldest point of
2407the tail may become not larger than a value to be assigned by <a href="#maximum_tailpoint_age">maximum_tailpoint_age</a>.</p>
2408</td> </tr> <tr> <td style="vertical-align: top;"> <p><a name="maximum_tailpoint_age"></a><b>maximum_tailpoint_</b>
2409<br> <b>age</b></p> </td> <td style="vertical-align: top;">R</td> <td style="vertical-align: top;">100000.0</td> <td style="vertical-align: top;"> <p>Maximum age that the
2410end point of a particle tail is allowed to have (in s).&nbsp; </p>
2411<p>If the temporal displacement between the oldest point of a
2412particle tail and the current position of the particle becomes larger
2413than the value given by <b>maximum_tailpoint_age</b>, this
2414oldest
2415point (which defines the end of the tail) is
2416removed. If this time is so small that the number of points defining
2417the particle tail do not exceed the value given by <b>maximum_number_of_tailpoints</b>,
2418then the length the particle tails is a measure for the distance the
2419particle travelled along during the time interval defined via <b>maximum_tailpoint_age</b>,
2420i.e. for the
2421particle velocity. Fast particles will have long tails, slow particles
2422shorter ones (note: this will not neccessarily hold if <a href="#minimum_tailpoint_distance">minimum_tailpoint_distance</a>
2423= <i>0.0</i>).</p> </td> </tr> <tr>
2424<td style="vertical-align: top;"> <p><a name="minimum_tailpoint_distance"></a><b>minimum_tailpoint_distance</b></p>
2425</td> <td style="vertical-align: top;">R</td>
2426<td style="vertical-align: top;"><i>0.0</i></td>
2427<td style="vertical-align: top;"> <p>Minimum
2428distance allowed between two adjacent points of a
2429particle tail (in m).&nbsp; </p> <p>In case of <b>minimum_tailpoint_distance</b>
2430&gt; <i>0.0 </i>the
2431particle tail is extended by a new point only if the distance between
2432its current position and the most recent tail point exceed the
2433distance given via <b>minimum_tailpoint_distance</b>.<br>
2434</p> <p>If the length of the particle tails shall be
2435proportional to
2436the respective particle velocity, the parameter <a href="#maximum_tailpoint_age">maximum_tailpoint_age</a>
2437must also be set appropriately. </p> <b>Note:</b><br>
2438A suitable choice of <b>minimum_tailpoint_distance</b>
2439&gt; <i>0.0</i> is recommended, because then the tail
2440coordinates of
2441slowly moving particles require less memory and can also be drawn
2442faster. The upper limit of <b>minimum_tailpoint_distance</b>
2443should be chosen in a way that the visualized particle
2444tails still appear as smooth lines. Example: with a model domain of
24451000 m and a monitor resolution of 1280 * 1024 pixels it
2446should be sufficient to set <b>minimum_tailpoint_distance</b>
2447= <i>5.0</i>
2448(m). </td> </tr> <tr> <td style="vertical-align: top;"><a name="number_of_particle_groups"></a><span style="font-weight: bold;">number_of_particle_groups</span><br>
2449</td> <td style="vertical-align: top;">I<br> </td>
2450<td style="vertical-align: top;">1<br> </td> <td style="vertical-align: top;">Number of particle groups to be
2451used.<br> <br>
2452Each particle group can be assigned its own source region (see <a href="#pdx">pdx</a>, <a href="#psl">psl</a>,
2453<a href="#psr">psr</a>, etc.), particle diameter (<a href="#radius">radius</a>) and particle density ratio (<a href="density_ratio">density_ratio</a>).<br><br>If
2454less values are given for <a href="#pdx">pdx</a>, <a href="#psl">psl</a>,
2455etc. than the number of particle groups, then the last value is used
2456for the remaining values (or the default value, if the user did not set
2457the parameter).<br> <br>
2458The maximum allowed number of particle groups is limited to <span style="font-style: italic;">10</span>.<br> </td>
2459</tr><tr><td align="left" valign="top"><a name="particles_per_point"></a><span style="font-weight: bold;">particles_per_point</span></td><td align="left" valign="top">I</td><td align="left" valign="top">1</td><td align="left" valign="top">Number of particles to be
2460started per point.<br><br>By default, one particle is
2461started at all points of the particle source,&nbsp;defined by <span style="font-family: Thorndale,serif;">the </span><span lang="en-GB"><font face="Thorndale, serif">package
2462parameters </font></span><a href="chapter_4.2.html#pst"><span lang="en-GB"><font face="Thorndale, serif">pst</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#psl"><span lang="en-GB"><font face="Thorndale, serif">psl</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#psr"><span lang="en-GB"><font face="Thorndale, serif">psr</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#pss"><span lang="en-GB"><font face="Thorndale, serif">pss</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#psn"><span lang="en-GB"><font face="Thorndale, serif">psn</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#psb"><span lang="en-GB"><font face="Thorndale, serif">psb</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#pdx"><span lang="en-GB"><font face="Thorndale, serif">pdx</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </