Changes between Version 10 and Version 11 of doc/app/bulk_cloud_parameters

Timestamp:

Nov 6, 2018 9:26:41 AM (6 years ago)

Author:

weniger

Comment:

--

doc/app/bulk_cloud_parameters

@@ -1 @@
-== Bulk Cloud Model Parameters ==
+= Bulk Cloud Model Parameters =
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+
+
+== Overview ==
 [[NoteBox(note,This page is part of the **Bulk Cloud Model** (BCM) documentation. \\ Since revision 3274 the bulk cloud model (before named with '''microphysics''') \\ is modularized and has a own parameter namelist. \\It contains a listing of all PALM input parameters used to steer the BCM. \\ For an overview of all BCM-related pages\, see the **[wiki:doc/tec/microphysics Bulk Cloud Model main page]**.)]]
+
+\\
+== Parameter list ==
+
 '''NAMELIST group name:''' [=#d3par '''{{{bulk_cloud_parameters}}}''']
 ||='''Parameter Name'''  =||='''[../fortrantypes FORTRAN]\\[../fortrantypes Type]'''  =||='''Default\\Value'''  =||='''Explanation'''  =||
@@ -41 +48 @@
       Two-moment cloud microphysics according to Seifert and Beheng (2006). It is also based on the saturation adjustment scheme to diagnose cloud water. The cloud drop number concentration is set via [#nc_const nc_const]. Rain water and hence precipitation is treated with two additional prognostic equations for rain water mixing ratio and rain drop concentration, including autoconversion, accretion, selfcollection, breakup, evaporation, and sedimentation. Ventilation effect on evaporation is steered by [#ventilation_effect ventilation_effect] and set to true per default. Sedimentation can be controlled via [#c_sedimentation c_sedimentation], [#limiter_sedimentation limiter_sedimentation]. Turbulence effects on accretion and autoconversion are steered via [#collision_turbulence collision_turbulence]. Additionally,  liquid cloud water is allowed to sediment too if [#cloud_water_sedimentation cloud_water_sedimentation] is set to true.\\\\
 '' 'morrison' '' \\\\
-      Two-moment cloud microphysics according to Seifert and Beheng (2006), Khairoutdinov and Kogan (2000), Khvorostynaov and Curry (2006) and Morrison and Grabowski (2007). The 'morrison'-scheme can be understood as an extension of the implemented 'seifert_beheng'-scheme. In comparison to the 'seifert_beheng'-scheme there are three main differences. First, instead of saturation adjustment the diffusional growth is parametrized while calculating condensation/evaporation rates explicitly. However, for a appropriate usage of this scheme the time-step must smaller than the diffusional growth relaxation time. Usually, this is in the order of 1-2 seconds. Second, the activation is considered with a simple Twomey activation-scheme. For this also Koehler-theory can take into account with the parameter [#curvature_solution_effects_bulk curvature_solution_effects_bulk] = T. The background aerosol concentration, which also determines the maximum number of activated cloud droplets, can be prescribed with [#na_init na_init]. Thirdly, the number concentration of cloud droplets (nc) and the cloud water mixing ratio (qc) are prognostic quantities. This allows a change of the cloud droplet number which is also considered for all microphysical processes. \\\\
+      Two-moment cloud microphysics according to Seifert and Beheng (2006), Khairoutdinov and Kogan (2000), Khvorostyanov and Curry (2006) and Morrison and Grabowski (2007). The 'morrison'-scheme can be understood as an extension of the implemented 'seifert_beheng'-scheme. In comparison to the 'seifert_beheng'-scheme there are three main differences. First, instead of saturation adjustment the diffusional growth is parametrized while calculating condensation/evaporation rates explicitly. However, for a appropriate usage of this scheme the time-step must smaller than the diffusional growth relaxation time. Usually, this is in the order of 1-2 seconds. Second, the activation is considered with a simple Twomey activation-scheme. For this also Koehler-theory can take into account with the parameter [#curvature_solution_effects_bulk curvature_solution_effects_bulk] = T. The background aerosol concentration, which also determines the maximum number of activated cloud droplets, can be prescribed with [#na_init na_init]. Thirdly, the number concentration of cloud droplets (nc) and the cloud water mixing ratio (qc) are prognostic quantities. This allows a change of the cloud droplet number which is also considered for all microphysical processes. \\\\
 }}}
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@@ -74 +81 @@
 }}}
 {{{#!td
-Parameter to control how often 2-moment cloud microphysics ([#cloud_scheme cloud_scheme] = 'seifert_beheng') are computed during a model time step. Using the default, cloud microphysics are computed once before the time step. Using call_microphysics_at_all_substeps = .T., cloud microphysics are computed before every substep of the applied time step scheme, which is, however, not necessary to gain acceptable results. Note that advection and diffusion of rainwater mixing ratio (qr) and rain drop concentration (nr) are not affected by this parameter (these processes are computed as any other scalar).
+Parameter to control how often 2-moment cloud microphysics ([#cloud_scheme cloud_scheme] = 'seifert_beheng') are computed during a model time step. Using the default, cloud microphysics are computed once before the time step. Using '''call_microphysics_at_all_substeps''' = .T., cloud microphysics are computed before every substep of the applied time step scheme, which is, however, not necessary to gain acceptable results. Note that advection and diffusion of rainwater mixing ratio (qr) and rain drop concentration (nr) are not affected by this parameter (these processes are computed as any other scalar).
 }}}
 |----------------
@@ -89 +96 @@
 Courant number for sedimentation process. 
 
-A Courant number that is too big inhibits microphysical interactions of the sedimented quantity. There is no need to use the limiter ([#limiter_sedimentation limiter_sedimentation]) if [#c_sedimentation c_sedimentation] <= 1.0.
+A Courant number that is too big inhibits microphysical interactions of the sedimented quantity. There is no need to use the limiter ([#limiter_sedimentation limiter_sedimentation]) if '''c_sedimentation''' <= 1.0.
 
 This parameter only comes into effect if the microphysical cloud scheme according to Seifert and Beheng (2006) is used ([#cloud_scheme cloud_scheme] = 'seifert_beheng').
@@ -104 +111 @@
 }}}
 {{{#!td
-Parameter to switch on an activation scheme which considers curvature and solution effects of cloud droplet activation. Therefore a parameterization of Khvorostyanov and Curry, 2006 is used. The physio-chemical aerosol properties can be prescribed with [#aerosol_bulk aerosol_bulk], [#dry_aerosol_radius dry_aerosol_radius] and [#sigma_bulk sigma_bulk]. 
+Parameter to switch on an activation scheme which considers curvature and solution effects of cloud droplet activation. Therefore a parameterization of Khvorostyanov and Curry (2006) is used. The physio-chemical aerosol properties can be prescribed with [#aerosol_bulk aerosol_bulk], [#dry_aerosol_radius dry_aerosol_radius] and [#sigma_bulk sigma_bulk]. 
 }}}
 |----------------
@@ -223 +230 @@
 This parameter only comes into effect if the microphysical cloud scheme according to Seifert and Beheng (2006) is used ([#cloud_scheme cloud_scheme] = 'seifert_beheng').
 }}}
+
+\\
+== References ==