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Timestamp:: May 25, 2018 9:01:27 AM (7 years ago)
Author:: schwenkel
Comment:: --

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doc/tec/microphysics

-                      v43
+                      v44
 instead of ''θ'' as described in Sect. [wiki:doc/tec/gov governing equations]. Since ''q'' and ''θ'',,l,, are conserved quantities for wet adiabatic processes, condensation/evaporation is not considered for these variables.
 PALM offers three different schemes ([#kessler1969 Kessler (1969)], [#seifert2001 Seifert and Beheng (2001],[#seifert2006  2006)], [#morrison2007 Morrison (2007)]) for the treatment of liquid phase microphysics. The [#kessler1969 Kessler (1969)] scheme provides a computational inexpensive way for the bulk microphysics. However, it only converts supersaturation into liquid water and considering autoconversion after a parameterization of [#kessler1969 Kessler (1969)].
+PALM offers three different schemes ([#kessler1969 Kessler (1969)], [#seifert2001 Seifert and Beheng (2001],[#seifert2006  2006)], [#morrison2007 Morrison et al. (2007)]) for the treatment of liquid phase microphysics. The [#kessler1969 Kessler (1969)] scheme provides a computational inexpensive way for the bulk microphysics. However, it only converts supersaturation into liquid water and considering autoconversion after a parameterization of [#kessler1969 Kessler (1969)].
 A more detailed parameterization is given by following the two-moment scheme of [#seifert2001 Seifert and Beheng (2001],[#seifert2006  2006)], which is based on the separation of the droplet spectrum into droplets with radii < 40 μm (cloud droplets) and droplets with radii ≥ 40 μm (rain droplets). Here, the model predicts the first two moments of these partial droplet spectra, namely cloud and rain
 …
 with ''N'',,c,, and ''q'',,c,, being a fixed parameter and a diagnostic quantity, respectively.
 The [#morrison2007 Morrison (2007)] microphysics scheme can be understood as an extension of the scheme of [#seifert2001 Seifert and Beheng (2001],[#seifert2006  2006)], where ''N'',,c,, and ''q'',,c,, are prognostic quantities as well. Moreover, using the [#morrison2007 Morrison (2007)] scheme includes an explicit calculation of diffusional growth and an activation parameterization.
 In the next subsections we will describe the diagnostic/prognostic determination (in dependence of the chosen scheme) of ''q'',,c,,. From Sect. [wiki:doc/tec/microphysics#Autoconversion autoconversion] on, the microphysical processes considered in the sink/source terms of ''θ'',,l,,, ''q'', ''N'',,r,, and ''q'',,r,,, as well as ''N'',,c,, and ''q'',,c,, for the [#morrison2007 Morrison (2007)] scheme.
+The [#morrison2007 Morrison et al. (2007)] microphysics scheme can be understood as an extension of the scheme of [#seifert2001 Seifert and Beheng (2001],[#seifert2006  2006)], where ''N'',,c,, and ''q'',,c,, are prognostic quantities as well. Moreover, using the [#morrison2007 Morrison et al. (2007)] scheme includes an explicit calculation of diffusional growth and an activation parameterization.
+In the next subsections we will describe the diagnostic/prognostic determination (in dependence of the chosen scheme) of ''q'',,c,,. From Sect. [wiki:doc/tec/microphysics#Autoconversion autoconversion] on, the microphysical processes considered in the sink/source terms of ''θ'',,l,,, ''q'', ''N'',,r,, and ''q'',,r,,, as well as ''N'',,c,, and ''q'',,c,, for the [#morrison2007 Morrison et al. (2007)] scheme.
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 == Activation of cloud droplets ==
 The use of the  [#morrison2007 Morrison et al (2007)] enables a prognostic equation for the cloud droplet number concentration. Here, it is assumed that cloud droplets are activated in dependence of the current supersaturation. This basic method is called Twomey activation scheme with the general form of
+The use of the  [#morrison2007 Morrison et al. (2007)] scheme enables a prognostic equation for the cloud droplet number concentration. Here, it is assumed that cloud droplets are activated in dependence of the current supersaturation. This basic method is called Twomey activation scheme with the general form of
 {{{
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 …
 }}}
 In contrast to that an explicit approach for the diffusional growth is applied in case of [#morrison2007 Morrison et al (2007)]. The condensation rate is calculated follwoing [#khairoutdinov2000 Khairoutdinov and Kogan (2000)] and given by
+In contrast to that an explicit approach for the diffusional growth is applied in case of [#morrison2007 Morrison et al. (2007)]. The condensation rate is calculated follwoing [#khairoutdinov2000 Khairoutdinov and Kogan (2000)] and given by
 {{{
 #!Latex