/[MITgcm]/manual/s_phys_pkgs/text/fizhi.tex
ViewVC logotype

Diff of /manual/s_phys_pkgs/text/fizhi.tex

Parent Directory Parent Directory | Revision Log Revision Log | View Revision Graph Revision Graph | View Patch Patch

revision 1.3 by molod, Wed Jan 28 18:27:15 2004 UTC revision 1.13 by molod, Wed Aug 3 17:55:20 2005 UTC
# Line 1  Line 1 
1  \section{Fizhi: High-end Atmospheric Physics}  \subsection{Fizhi: High-end Atmospheric Physics}
2    \label{sec:pkg:fizhi}
3    \begin{rawhtml}
4    <!-- CMIREDIR:package_fizhi: -->
5    \end{rawhtml}
6  \input{texinputs/epsf.tex}  \input{texinputs/epsf.tex}
7    
8  \subsection{Introduction}  \subsubsection{Introduction}
9  The fizhi (high-end atmospheric physics) package includes a collection of state-of-the-art  The fizhi (high-end atmospheric physics) package includes a collection of state-of-the-art
10  physical parameterizations for atmospheric radiation, cumulus convection, atmospheric  physical parameterizations for atmospheric radiation, cumulus convection, atmospheric
11  boundary layer turbulence, and land surface processes.  boundary layer turbulence, and land surface processes. The collection of atmospheric
12    physics parameterizations were originally used together as part of the GEOS-3
13    (Goddard Earth Observing System-3) GCM developed at the NASA/Goddard Global Modelling
14    and Assimilation Office (GMAO).
15    
16  % *************************************************************************  % *************************************************************************
17  % *************************************************************************  % *************************************************************************
18    
19  \subsection{Equations}  \subsubsection{Equations}
20    
21  \subsubsection{Moist Convective Processes}  Moist Convective Processes:
22    
23  \subsubsection{Sub-grid and Large-scale Convection}  \paragraph{Sub-grid and Large-scale Convection}
24  \label{sec:fizhi:mc}  \label{sec:fizhi:mc}
25    
26  Sub-grid scale cumulus convection is parameterized using the Relaxed Arakawa  Sub-grid scale cumulus convection is parameterized using the Relaxed Arakawa
27  Schubert (RAS) scheme of Moorthi and Suarez (1992), which is a linearized Arakawa Schubert  Schubert (RAS) scheme of \cite{moorsz:92}, which is a linearized Arakawa Schubert
28  type scheme.  RAS predicts the mass flux from an ensemble of clouds.  Each subensemble is identified  type scheme.  RAS predicts the mass flux from an ensemble of clouds.  Each subensemble is identified
29  by its entrainment rate and level of neutral bouyancy which are determined by the grid-scale properties.  by its entrainment rate and level of neutral bouyancy which are determined by the grid-scale properties.
30    
# Line 39  where we have used the hydrostatic equat Line 46  where we have used the hydrostatic equat
46  The entrainment parameter, $\lambda$, characterizes a particular subensemble based on its  The entrainment parameter, $\lambda$, characterizes a particular subensemble based on its
47  detrainment level, and is obtained by assuming that the level of detrainment is the level of neutral  detrainment level, and is obtained by assuming that the level of detrainment is the level of neutral
48  buoyancy, ie., the level at which the moist static energy of the cloud, $h_c$, is equal  buoyancy, ie., the level at which the moist static energy of the cloud, $h_c$, is equal
49  to the saturation moist static energy of the environment, $h^*$.  Following Moorthi and Suarez (1992),  to the saturation moist static energy of the environment, $h^*$.  Following \cite{moorsz:92},
50  $\lambda$ may be written as  $\lambda$ may be written as
51  \[  \[
52  \lambda = { {h_B - h^*_D} \over { {c_p \over g} {\int_{P_D}^{P_B}\theta(h^*_D-h)dP^{\kappa}}} } ,  \lambda = { {h_B - h^*_D} \over { {c_p \over g} {\int_{P_D}^{P_B}\theta(h^*_D-h)dP^{\kappa}}} } ,
# Line 97  $\alpha$ of the total adjustment. The pa Line 104  $\alpha$ of the total adjustment. The pa
104  towards equillibrium.    towards equillibrium.  
105    
106  In addition to the RAS cumulus convection scheme, the fizhi package employs a  In addition to the RAS cumulus convection scheme, the fizhi package employs a
107  Kessler-type scheme for the re-evaporation of falling rain (Sud and Molod, 1988), which  Kessler-type scheme for the re-evaporation of falling rain (\cite{sudm:88}), which
108  correspondingly adjusts the temperature assuming $h$ is conserved. RAS in its current  correspondingly adjusts the temperature assuming $h$ is conserved. RAS in its current
109  formulation assumes that all cloud water is deposited into the detrainment level as rain.  formulation assumes that all cloud water is deposited into the detrainment level as rain.
110  All of the rain is available for re-evaporation, which begins in the level below detrainment.  All of the rain is available for re-evaporation, which begins in the level below detrainment.
# Line 120  The large-scale precipitation re-evapora Line 127  The large-scale precipitation re-evapora
127  lower layers in a process identical to the re-evaporation of convective rain.  lower layers in a process identical to the re-evaporation of convective rain.
128    
129    
130  \subsubsection{Cloud Formation}  \paragraph{Cloud Formation}
131  \label{sec:fizhi:clouds}  \label{sec:fizhi:clouds}
132    
133  Convective and large-scale cloud fractons which are used for cloud-radiative interactions are determined  Convective and large-scale cloud fractons which are used for cloud-radiative interactions are determined
# Line 162  RH_{min} & = & 0.75 \nonumber \\ Line 169  RH_{min} & = & 0.75 \nonumber \\
169    
170  These cloud fractions are suppressed, however, in regions where the convective  These cloud fractions are suppressed, however, in regions where the convective
171  sub-cloud layer is conditionally unstable.  The functional form of $RH_c$ is shown in  sub-cloud layer is conditionally unstable.  The functional form of $RH_c$ is shown in
172  Figure (\ref{fig:fizhi:rhcrit}).  Figure (\ref{fig.rhcrit}).
173    
174  \begin{figure*}[htbp]  \begin{figure*}[htbp]
175    \vspace{0.4in}    \vspace{0.4in}
176    \centerline{  \epsfysize=4.0in  \epsfbox{rhcrit.ps}}    \centerline{  \epsfysize=4.0in  \epsfbox{part6/rhcrit.ps}}
177    \vspace{0.4in}    \vspace{0.4in}
178    \caption  [Critical Relative Humidity for Clouds.]    \caption  [Critical Relative Humidity for Clouds.]
179              {Critical Relative Humidity for Clouds.}              {Critical Relative Humidity for Clouds.}
180    \label{fig:fizhi:rhcrit}    \label{fig.rhcrit}
181  \end{figure*}  \end{figure*}
182    
183  The total cloud fraction in a grid box is determined by the larger of the two cloud fractions:  The total cloud fraction in a grid box is determined by the larger of the two cloud fractions:
# Line 182  F_{CLD} = \max \left[ F_{RAS},F_{LS} \ri Line 189  F_{CLD} = \max \left[ F_{RAS},F_{LS} \ri
189  Finally, cloud fractions are time-averaged between calls to the radiation packages.  Finally, cloud fractions are time-averaged between calls to the radiation packages.
190    
191    
192  \subsubsection{Radiation}  Radiation:
193    
194  The parameterization of radiative heating in the fizhi package includes effects  The parameterization of radiative heating in the fizhi package includes effects
195  from both shortwave and longwave processes.  from both shortwave and longwave processes.
# Line 217  The solar constant value used in the pac Line 224  The solar constant value used in the pac
224  and a $CO_2$ mixing ratio of 330 ppm.  and a $CO_2$ mixing ratio of 330 ppm.
225  For the ozone mixing ratio, monthly mean zonally averaged  For the ozone mixing ratio, monthly mean zonally averaged
226  climatological values specified as a function  climatological values specified as a function
227  of latitude and height (Rosenfield, et al., 1987) are linearly interpolated to the current time.  of latitude and height (\cite{rosen:87}) are linearly interpolated to the current time.
228    
229    
230  \subsubsection{Shortwave Radiation}  \paragraph{Shortwave Radiation}
231    
232  The shortwave radiation package used in the package computes solar radiative  The shortwave radiation package used in the package computes solar radiative
233  heating due to the absoption by water vapor, ozone, carbon dioxide, oxygen,  heating due to the absoption by water vapor, ozone, carbon dioxide, oxygen,
234  clouds, and aerosols and due to the  clouds, and aerosols and due to the
235  scattering by clouds, aerosols, and gases.  scattering by clouds, aerosols, and gases.
236  The shortwave radiative processes are described by  The shortwave radiative processes are described by
237  Chou (1990,1992). This shortwave package  \cite{chou:90,chou:92}. This shortwave package
238  uses the Delta-Eddington approximation to compute the  uses the Delta-Eddington approximation to compute the
239  bulk scattering properties of a single layer following King and Harshvardhan (JAS, 1986).  bulk scattering properties of a single layer following King and Harshvardhan (JAS, 1986).
240  The transmittance and reflectance of diffuse radiation  The transmittance and reflectance of diffuse radiation
241  follow the procedures of Sagan and Pollock (JGR, 1967) and Lacis and Hansen (JAS, 1974).  follow the procedures of Sagan and Pollock (JGR, 1967) and \cite{lhans:74}.
242    
243  Highly accurate heating rate calculations are obtained through the use  Highly accurate heating rate calculations are obtained through the use
244  of an optimal grouping strategy of spectral bands.  By grouping the UV and visible regions  of an optimal grouping strategy of spectral bands.  By grouping the UV and visible regions
# Line 301  cloud cover of all the layers in the gro Line 308  cloud cover of all the layers in the gro
308  of a given layer is then scaled for both the direct (as a function of the  of a given layer is then scaled for both the direct (as a function of the
309  solar zenith angle) and diffuse beam radiation  solar zenith angle) and diffuse beam radiation
310  so that the grouped layer reflectance is the same as the original reflectance.  so that the grouped layer reflectance is the same as the original reflectance.
311  The solar flux is computed for each of the eight cloud realizations possible  The solar flux is computed for each of eight cloud realizations possible within this
 (see Figure \ref{fig:fizhi:cloud}) within this  
312  low/middle/high classification, and appropriately averaged to produce the net solar flux.  low/middle/high classification, and appropriately averaged to produce the net solar flux.
313    
314  \begin{figure*}[htbp]  \paragraph{Longwave Radiation}
   \vspace{0.4in}  
   \centerline{  \epsfysize=4.0in  %\epsfbox{rhcrit.ps}  
              }  
   \vspace{0.4in}  
   \caption  {Low-Middle-High Cloud Configurations}  
   \label{fig:fizhi:cloud}  
 \end{figure*}  
315    
316    The longwave radiation package used in the fizhi package is thoroughly described by \cite{chsz:94}.
 \subsubsection{Longwave Radiation}  
   
 The longwave radiation package used in the fizhi package is thoroughly described by Chou and Suarez (1994).  
317  As described in that document, IR fluxes are computed due to absorption by water vapor, carbon  As described in that document, IR fluxes are computed due to absorption by water vapor, carbon
318  dioxide, and ozone.  The spectral bands together with their absorbers and parameterization methods,  dioxide, and ozone.  The spectral bands together with their absorbers and parameterization methods,
319  configured for the fizhi package, are shown in Table \ref{tab:fizhi:longwave}.  configured for the fizhi package, are shown in Table \ref{tab:fizhi:longwave}.
# Line 353  Band & Spectral Range (cm$^{-1}$) & Abso Line 349  Band & Spectral Range (cm$^{-1}$) & Abso
349  \end{tabular}  \end{tabular}
350  \end{center}  \end{center}
351  \vspace{0.1in}  \vspace{0.1in}
352  \caption{IR Spectral Bands, Absorbers, and Parameterization Method (from Chou and Suarez, 1994)}  \caption{IR Spectral Bands, Absorbers, and Parameterization Method (from \cite{chsz:94})}
353  \label{tab:fizhi:longwave}  \label{tab:fizhi:longwave}
354  \end{table}  \end{table}
355    
# Line 383  For groups and/or levels outside the ran Line 379  For groups and/or levels outside the ran
379  assigned.  assigned.
380    
381    
382  \subsubsection{Cloud-Radiation Interaction}  \paragraph{Cloud-Radiation Interaction}
383  \label{sec:fizhi:radcloud}  \label{sec:fizhi:radcloud}
384    
385  The cloud fractions and diagnosed cloud liquid water produced by moist processes  The cloud fractions and diagnosed cloud liquid water produced by moist processes
# Line 424  The cloud fraction values are time-avera Line 420  The cloud fraction values are time-avera
420  hours).  Therefore, in a time-averaged sense, both convective and large-scale  hours).  Therefore, in a time-averaged sense, both convective and large-scale
421  cloudiness can exist in a given grid-box.    cloudiness can exist in a given grid-box.  
422    
423  \subsubsection{Turbulence}  \paragraph{Turbulence}:
424    
425  Turbulence is parameterized in the fizhi package to account for its contribution to the  Turbulence is parameterized in the fizhi package to account for its contribution to the
426  vertical exchange of heat, moisture, and momentum.    vertical exchange of heat, moisture, and momentum.  
427  The turbulence scheme is invoked every 30 minutes, and employs a backward-implicit iterative  The turbulence scheme is invoked every 30 minutes, and employs a backward-implicit iterative
# Line 454  Within the atmosphere, the time evolutio Line 451  Within the atmosphere, the time evolutio
451  of second turbulent moments is explicitly modeled by representing the third moments in terms of  of second turbulent moments is explicitly modeled by representing the third moments in terms of
452  the first and second moments.  This approach is known as a second-order closure modeling.  the first and second moments.  This approach is known as a second-order closure modeling.
453  To simplify and streamline the computation of the second moments, the level 2.5 assumption  To simplify and streamline the computation of the second moments, the level 2.5 assumption
454  of Mellor and Yamada (1974) and Yamada (1977) is employed, in which only the turbulent  of Mellor and Yamada (1974) and \cite{yam:77} is employed, in which only the turbulent
455  kinetic energy (TKE),  kinetic energy (TKE),
456    
457  \[ {\h}{q^2}={\overline{{u^{\prime}}^2}}+{\overline{{v^{\prime}}^2}}+{\overline{{w^{\prime}}^2}}, \]  \[ {\h}{q^2}={\overline{{u^{\prime}}^2}}+{\overline{{v^{\prime}}^2}}+{\overline{{w^{\prime}}^2}}, \]
# Line 488  of TKE. Line 485  of TKE.
485    
486  In the level 2.5 approach, the vertical fluxes of the scalars $\theta_v$ and $q$ and the  In the level 2.5 approach, the vertical fluxes of the scalars $\theta_v$ and $q$ and the
487  wind components $u$ and $v$ are expressed in terms of the diffusion coefficients $K_h$ and  wind components $u$ and $v$ are expressed in terms of the diffusion coefficients $K_h$ and
488  $K_m$, respectively.  In the statisically realizable level 2.5 turbulence scheme of Helfand  $K_m$, respectively.  In the statisically realizable level 2.5 turbulence scheme of
489  and Labraga (1988), these diffusion coefficients are expressed as  \cite{helflab:88}, these diffusion coefficients are expressed as
490    
491  \[  \[
492  K_h  K_h
# Line 564  where $\psi_h$ is the surface layer non- Line 561  where $\psi_h$ is the surface layer non-
561  \]  \]
562  Here $\phi_h$ is the similarity function of $\zeta$, which expresses the stability dependance of  Here $\phi_h$ is the similarity function of $\zeta$, which expresses the stability dependance of
563  the temperature and moisture gradients, and is specified differently for stable and unstable  the temperature and moisture gradients, and is specified differently for stable and unstable
564  layers according to Helfand and Schubert, 1995.  layers according to \cite{helfschu:95}.
565    
566  $\psi_g$ is the non-dimensional temperature or moisture gradient in the viscous sublayer,  $\psi_g$ is the non-dimensional temperature or moisture gradient in the viscous sublayer,
567  which is the mosstly laminar region between the surface and the tops of the roughness  which is the mosstly laminar region between the surface and the tops of the roughness
568  elements, in which temperature and moisture gradients can be quite large.  elements, in which temperature and moisture gradients can be quite large.
569  Based on Yaglom and Kader (1974):  Based on \cite{yagkad:74}:
570  \[  \[
571  \psi_{g} = { 0.55 (Pr^{2/3} - 0.2) \over \nu^{1/2} }  \psi_{g} = { 0.55 (Pr^{2/3} - 0.2) \over \nu^{1/2} }
572  (h_{0}u_{*} - h_{0_{ref}}u_{*_{ref}})^{1/2}  (h_{0}u_{*} - h_{0_{ref}}u_{*_{ref}})^{1/2}
# Line 583  The surface roughness length over oceans Line 580  The surface roughness length over oceans
580  {z_0} = c_1u^3_* + c_2u^2_* + c_3u_* + c_4 + {c_5 \over {u_*}}  {z_0} = c_1u^3_* + c_2u^2_* + c_3u_* + c_4 + {c_5 \over {u_*}}
581  \]  \]
582  where the constants are chosen to interpolate between the reciprocal relation of  where the constants are chosen to interpolate between the reciprocal relation of
583  Kondo(1975) for weak winds, and the piecewise linear relation of Large and Pond(1981)  \cite{kondo:75} for weak winds, and the piecewise linear relation of \cite{larpond:81}
584  for moderate to large winds.  Roughness lengths over land are specified  for moderate to large winds.  Roughness lengths over land are specified
585  from the climatology of Dorman and Sellers (1989).  from the climatology of \cite{dorsell:89}.
586    
587  For an unstable surface layer, the stability functions, chosen to interpolate between the  For an unstable surface layer, the stability functions, chosen to interpolate between the
588  condition of small values of $\beta$ and the convective limit, are the KEYPS function  condition of small values of $\beta$ and the convective limit, are the KEYPS function
589  (Panofsky, 1973) for momentum, and its generalization for heat and moisture:    (\cite{pano:73}) for momentum, and its generalization for heat and moisture:  
590  \[  \[
591  {\phi_m}^4 - 18 \zeta {\phi_m}^3 = 1 \hspace{1cm} ; \hspace{1cm}  {\phi_m}^4 - 18 \zeta {\phi_m}^3 = 1 \hspace{1cm} ; \hspace{1cm}
592  {\phi_h}^2 - 18 \zeta {\phi_h}^3 = 1 \hspace{1cm} .  {\phi_h}^2 - 18 \zeta {\phi_h}^3 = 1 \hspace{1cm} .
# Line 598  The function for heat and moisture assur Line 595  The function for heat and moisture assur
595  speed approaches zero.  speed approaches zero.
596    
597  For a stable surface layer, the stability functions are the observationally  For a stable surface layer, the stability functions are the observationally
598  based functions of Clarke (1970),  slightly modified for  based functions of \cite{clarke:70},  slightly modified for
599  the momemtum flux:    the momemtum flux:  
600  \[  \[
601  {\phi_m} = { { 1 + 5 {{\zeta}_1} } \over { 1 + 0.00794 {{\zeta}_1}  {\phi_m} = { { 1 + 5 {{\zeta}_1} } \over { 1 + 0.00794 {{\zeta}_1}
# Line 613  land. Line 610  land.
610  Once all the diffusion coefficients are calculated, the diffusion equations are solved numerically  Once all the diffusion coefficients are calculated, the diffusion equations are solved numerically
611  using an implicit backward operator.  using an implicit backward operator.
612    
613  \subsubsection{Atmospheric Boundary Layer}  \paragraph{Atmospheric Boundary Layer}
614    
615  The depth of the atmospheric boundary layer (ABL) is diagnosed by the parameterization as the  The depth of the atmospheric boundary layer (ABL) is diagnosed by the parameterization as the
616  level at which the turbulent kinetic energy is reduced to a tenth of its maximum near surface value.  level at which the turbulent kinetic energy is reduced to a tenth of its maximum near surface value.
617  The vertical structure of the ABL is explicitly resolved by the lowest few (3-8) model layers.  The vertical structure of the ABL is explicitly resolved by the lowest few (3-8) model layers.
618    
619  \subsubsection{Surface Energy Budget}  \paragraph{Surface Energy Budget}
620    
621  The ground temperature equation is solved as part of the turbulence package  The ground temperature equation is solved as part of the turbulence package
622  using a backward implicit time differencing scheme:  using a backward implicit time differencing scheme:
# Line 656  be $3 \hspace{.1cm} m$ where sea ice is Line 653  be $3 \hspace{.1cm} m$ where sea ice is
653  surface temperature of the ice.  surface temperature of the ice.
654    
655  $C_g$ is the total heat capacity of the ground, obtained by solving a heat diffusion equation  $C_g$ is the total heat capacity of the ground, obtained by solving a heat diffusion equation
656  for the penetration of the diurnal cycle into the ground (Blackadar, 1977), and is given by:  for the penetration of the diurnal cycle into the ground (\cite{black:77}), and is given by:
657  \[  \[
658  C_g = \sqrt{ {\lambda C_s \over 2\omega} } = \sqrt{(0.386 + 0.536W + 0.15W^2)2\times10^{-3}  C_g = \sqrt{ {\lambda C_s \over 2\omega} } = \sqrt{(0.386 + 0.536W + 0.15W^2)2\times10^{-3}
659  {86400 \over 2 \pi} } \, \, .  {86400 \over 2 \pi} } \, \, .
# Line 668  by $2 \pi$ $radians/ Line 665  by $2 \pi$ $radians/
665  day$, and the expression for $C_s$, the heat capacity per unit volume at the surface,  day$, and the expression for $C_s$, the heat capacity per unit volume at the surface,
666  is a function of the ground wetness, $W$.  is a function of the ground wetness, $W$.
667    
668  \subsubsection{Land Surface Processes}  Land Surface Processes:
669    
670  \subsubsection{Surface Type}  \paragraph{Surface Type}
671  The fizhi package surface Types are designated using the Koster-Suarez (1992) mosaic  The fizhi package surface Types are designated using the Koster-Suarez (\cite{ks:91,ks:92})
672  philosophy which allows multiple ``tiles'', or multiple surface types, in any one  Land Surface Model (LSM) mosaic philosophy which allows multiple ``tiles'', or multiple surface
673  grid cell. The Koster-Suarez Land Surface Model (LSM) surface type classifications  types, in any one grid cell. The Koster-Suarez LSM surface type classifications
674  are shown in Table \ref{tab:fizhi:surftype}. The surface types and the percent of the grid  are shown in Table \ref{tab:fizhi:surftype}. The surface types and the percent of the grid
675  cell occupied by any surface type were derived from the surface classification of  cell occupied by any surface type were derived from the surface classification of
676  Defries and Townshend (1994), and information about the location of permanent  \cite{deftow:94}, and information about the location of permanent
677  ice was obtained from the classifications of Dorman and Sellers (1989).  ice was obtained from the classifications of \cite{dorsell:89}.
678  The surface type for the \txt GCM grid is shown in Figure \ref{fig:fizhi:surftype}.  The surface type map for a $1^\circ$ grid is shown in Figure \ref{fig:fizhi:surftype}.
679  The determination of the land or sea category of surface type was made from NCAR's  The determination of the land or sea category of surface type was made from NCAR's
680  10 minute by 10 minute Navy topography  10 minute by 10 minute Navy topography
681  dataset, which includes information about the percentage of water-cover at any point.  dataset, which includes information about the percentage of water-cover at any point.
682  The data were averaged to the model's \fxf and \txt grid resolutions,  The data were averaged to the model's grid resolutions,
683  and any grid-box whose averaged water percentage was $\geq 60 \%$ was  and any grid-box whose averaged water percentage was $\geq 60 \%$ was
684  defined as a water point. The \fxf grid Land-Water designation was further modified  defined as a water point. The Land-Water designation was further modified
685  subjectively to ensure sufficient representation from small but isolated land and water regions.  subjectively to ensure sufficient representation from small but isolated land and water regions.
686    
687  \begin{table}  \begin{table}
# Line 715  and surface albedo.} Line 712  and surface albedo.}
712    
713    
714  \begin{figure*}[htbp]  \begin{figure*}[htbp]
715    \centerline{  \epsfysize=7in  \epsfbox{surftypes.ps}}    \begin{center}
716    \vspace{0.3in}    \rotatebox{270}{\resizebox{90mm}{!}{\includegraphics{part6/surftypes.eps}}}
717    \caption  {Surface Type Compinations at \txt resolution.}    \rotatebox{270}{\resizebox{100mm}{!}{\includegraphics{part6/surftypes.descrip.eps}}}
718      \end{center}
719      \vspace{0.2in}
720      \caption  {Surface Type Combinations at $1^\circ$ resolution.}
721    \label{fig:fizhi:surftype}    \label{fig:fizhi:surftype}
722  \end{figure*}  \end{figure*}
723    
724  \begin{figure*}[htbp]  % \rotatebox{270}{\centerline{  \epsfysize=4in  \epsfbox{part6/surftypes.eps}}}
725    \centerline{  \epsfysize=7in  \epsfbox{surftypes.descrip.ps}}  % \rotatebox{270}{\centerline{  \epsfysize=4in  \epsfbox{part6/surftypes.descrip.eps}}}
726    \vspace{0.3in}  %\begin{figure*}[htbp]
727    \caption  {Surface Type Descriptions.}  %  \centerline{  \epsfysize=4in  \epsfbox{part6/surftypes.descrip.ps}}
728    \label{fig:fizhi:surftype.desc}  %  \vspace{0.3in}
729  \end{figure*}  %  \caption  {Surface Type Descriptions.}
730    %  \label{fig:fizhi:surftype.desc}
731    %\end{figure*}
732    
733    
734  \subsubsection{Surface Roughness}  \paragraph{Surface Roughness}
735  The surface roughness length over oceans is computed iteratively with the wind  The surface roughness length over oceans is computed iteratively with the wind
736  stress by the surface layer parameterization (Helfand and Schubert, 1991).  stress by the surface layer parameterization (\cite{helfschu:95}).
737  It employs an interpolation between the functions of Large and Pond (1981)  It employs an interpolation between the functions of \cite{larpond:81}
738  for high winds and of Kondo (1975) for weak winds.  for high winds and of \cite{kondo:75} for weak winds.
739    
740    
741  \subsubsection{Albedo}  \paragraph{Albedo}
742  The surface albedo computation, described in Koster and Suarez (1991),  The surface albedo computation, described in \cite{ks:91},
743  employs the ``two stream'' approximation used in Sellers' (1987) Simple Biosphere (SiB)  employs the ``two stream'' approximation used in Sellers' (1987) Simple Biosphere (SiB)
744  Model which distinguishes between the direct and diffuse albedos in the visible  Model which distinguishes between the direct and diffuse albedos in the visible
745  and in the near infra-red spectral ranges. The albedos are functions of the observed  and in the near infra-red spectral ranges. The albedos are functions of the observed
# Line 746  sun), the greenness fraction, the vegeta Line 748  sun), the greenness fraction, the vegeta
748  Modifications are made to account for the presence of snow, and its depth relative  Modifications are made to account for the presence of snow, and its depth relative
749  to the height of the vegetation elements.  to the height of the vegetation elements.
750    
751  \subsubsection{Gravity Wave Drag}  \paragraph{Gravity Wave Drag}:
752  The fizhi package employs the gravity wave drag scheme of Zhou et al. (1996).  
753    The fizhi package employs the gravity wave drag scheme of \cite{zhouetal:95}).
754  This scheme is a modified version of Vernekar et al. (1992),  This scheme is a modified version of Vernekar et al. (1992),
755  which was based on Alpert et al. (1988) and Helfand et al. (1987).    which was based on Alpert et al. (1988) and Helfand et al. (1987).  
756  In this version, the gravity wave stress at the surface is  In this version, the gravity wave stress at the surface is
# Line 764  A modification introduced by Zhou et al. Line 767  A modification introduced by Zhou et al.
767  escape through the top of the model, although this effect is small for the current 70-level model.    escape through the top of the model, although this effect is small for the current 70-level model.  
768  The subgrid scale standard deviation is defined by $h$, and is not allowed to exceed 400 m.  The subgrid scale standard deviation is defined by $h$, and is not allowed to exceed 400 m.
769    
770  The effects of using this scheme within a GCM are shown in Takacs and Suarez (1996).  The effects of using this scheme within a GCM are shown in \cite{taksz:96}.
771  Experiments using the gravity wave drag parameterization yielded significant and  Experiments using the gravity wave drag parameterization yielded significant and
772  beneficial impacts on both the time-mean flow and the transient statistics of the  beneficial impacts on both the time-mean flow and the transient statistics of the
773  a GCM climatology, and have eliminated most of the worst dynamically driven biases  a GCM climatology, and have eliminated most of the worst dynamically driven biases
# Line 780  of mountain torque (through a redistribu Line 783  of mountain torque (through a redistribu
783  convergence (through a reduction in the flux of westerly momentum by transient flow eddies).    convergence (through a reduction in the flux of westerly momentum by transient flow eddies).  
784    
785    
786  \subsubsection{Boundary Conditions and other Input Data}  Boundary Conditions and other Input Data:
787    
788  Required fields which are not explicitly predicted or diagnosed during model execution must  Required fields which are not explicitly predicted or diagnosed during model execution must
789  either be prescribed internally or obtained from external data sets.  In the fizhi package these  either be prescribed internally or obtained from external data sets.  In the fizhi package these
# Line 788  fields include:  sea surface temperature Line 791  fields include:  sea surface temperature
791  vegetation index, and the radiation-related background levels of: ozone, carbon dioxide,  vegetation index, and the radiation-related background levels of: ozone, carbon dioxide,
792  and stratospheric moisture.  and stratospheric moisture.
793    
794  Boundary condition data sets are available at the model's \fxf and \txt  Boundary condition data sets are available at the model's
795  resolutions for either climatological or yearly varying conditions.  resolutions for either climatological or yearly varying conditions.
796  Any frequency of boundary condition data can be used in the fizhi package;  Any frequency of boundary condition data can be used in the fizhi package;
797  however, the current selection of data is summarized in Table \ref{tab:fizhi:bcdata}\@.  however, the current selection of data is summarized in Table \ref{tab:fizhi:bcdata}\@.
798  The time mean values are interpolated during each model timestep to the  The time mean values are interpolated during each model timestep to the
799  current time. Future model versions will incorporate boundary conditions at  current time.
 higher spatial \mbox{($1^\circ$ x $1^\circ$)} resolutions.  
800    
801  \begin{table}[htb]  \begin{table}[htb]
802  \begin{center}  \begin{center}
# Line 816  current years and frequencies available. Line 818  current years and frequencies available.
818  \end{table}  \end{table}
819    
820    
821  \subsubsection{Topography and Topography Variance}  \paragraph{Topography and Topography Variance}
822    
823  Surface geopotential heights are provided from an averaging of the Navy 10 minute  Surface geopotential heights are provided from an averaging of the Navy 10 minute
824  by 10 minute dataset supplied by the National Center for Atmospheric Research (NCAR) to the  by 10 minute dataset supplied by the National Center for Atmospheric Research (NCAR) to the
825  model's grid resolution. The original topography is first rotated to the proper grid-orientation  model's grid resolution. The original topography is first rotated to the proper grid-orientation
826  which is being run, and then    which is being run, and then  averages the data to the model resolution.  
 averages the data to the model resolution.    
 The averaged topography is then passed through a Lanczos (1966) filter in both dimensions  
 which removes the smallest  
 scales while inhibiting Gibbs phenomena.    
   
 In one dimension, we may define a cyclic function in $x$ as:  
 \begin{equation}  
 f(x) = {a_0 \over 2} + \sum_{k=1}^N \left( a_k \cos(kx) + b_k \sin(kx) \right)  
 \label{eq:fizhi:filt}  
 \end{equation}  
 where $N = { {\rm IM} \over 2 }$ and ${\rm IM}$ is the total number of points in the $x$ direction.  
 Defining $\Delta x = { 2 \pi \over {\rm IM}}$, we may define the average of $f(x)$ over a  
 $2 \Delta x$ region as:  
   
 \begin{equation}  
 \overline {f(x)} = {1 \over {2 \Delta x}} \int_{x-\Delta x}^{x+\Delta x} f(x^{\prime}) dx^{\prime}  
 \label{eq:fizhi:fave1}  
 \end{equation}  
   
 Using equation (\ref{eq:fizhi:filt}) in equation (\ref{eq:fizhi:fave1}) and integrating, we may write:  
   
 \begin{equation}  
 \overline {f(x)} = {a_0 \over 2} + {1 \over {2 \Delta x}}  
 \sum_{k=1}^N \left [  
 \left. a_k { \sin(kx^{\prime}) \over k } \right /_{x-\Delta x}^{x+\Delta x} -  
 \left. b_k { \cos(kx^{\prime}) \over k } \right /_{x-\Delta x}^{x+\Delta x}  
 \right]  
 \end{equation}  
 or  
   
 \begin{equation}  
 \overline {f(x)} = {a_0 \over 2} + \sum_{k=1}^N {\sin(k \Delta x) \over {k \Delta x}}  
 \left( a_k \cos(kx) + b_k \sin(kx) \right)  
 \label{eq:fizhi:fave2}  
 \end{equation}  
   
 Thus, the Fourier wave amplitudes are simply modified by the Lanczos filter response  
 function ${\sin(k\Delta x) \over {k \Delta x}}$.  This may be compared with an $mth$-order  
 Shapiro (1970) filter response function, defined as $1-\sin^m({k \Delta x \over 2})$,  
 shown in Figure \ref{fig:fizhi:lanczos}.  
 It should be noted that negative values in the topography resulting from  
 the filtering procedure are {\em not} filled.  
827    
828  \begin{figure*}[htbp]  The standard deviation of the subgrid-scale topography is computed by interpolating the 10 minute
829    \centerline{  \epsfysize=7.0in  \epsfbox{lanczos.ps}}  data to the model's resolution and re-interpolating back to the 10 minute by 10 minute resolution.
   \caption{ \label{fig:fizhi:lanczos} Comparison between the Lanczos and $mth$-order Shapiro filter  
   response functions for $m$ = 2, 4, and 8. }  
 \end{figure*}  
   
 The standard deviation of the subgrid-scale topography  
 is computed from a modified version of the the Navy 10 minute by 10 minute dataset.  
 The 10 minute by 10 minute topography is passed through a wavelet  
 filter in both dimensions which removes the scale smaller than 20 minutes.  
 The topography is then averaged to $1^\circ x 1^\circ$ grid resolution, and then  
 re-interpolated back to the 10 minute by 10 minute resolution.  
830  The sub-grid scale variance is constructed based on this smoothed dataset.  The sub-grid scale variance is constructed based on this smoothed dataset.
831    
832    
833  \subsubsection{Upper Level Moisture}  \paragraph{Upper Level Moisture}
834  The fizhi package uses climatological water vapor data above 100 mb from the Stratospheric Aerosol and Gas  The fizhi package uses climatological water vapor data above 100 mb from the Stratospheric Aerosol and Gas
835  Experiment (SAGE) as input into the model's radiation packages.  The SAGE data is archived  Experiment (SAGE) as input into the model's radiation packages.  The SAGE data is archived
836  as monthly zonal means at 5$^\circ$ latitudinal resolution.  The data is interpolated to the  as monthly zonal means at 5$^\circ$ latitudinal resolution.  The data is interpolated to the
# Line 888  model's grid location and current time, Line 838  model's grid location and current time,
838  the model's moisture data is used.  Above 100 mb, the SAGE data is used.  Between 100 and 300 mb,  the model's moisture data is used.  Above 100 mb, the SAGE data is used.  Between 100 and 300 mb,
839  a linear interpolation (in pressure) is performed using the data from SAGE and the GCM.  a linear interpolation (in pressure) is performed using the data from SAGE and the GCM.
840    
841    
842    \subsubsection{Fizhi Diagnostics}
843    
844    Fizhi Diagnostic Menu:
845    \label{sec:fizhi-diagnostics:menu}
846    
847    \begin{tabular}{llll}
848    \hline\hline
849     NAME & UNITS & LEVELS & DESCRIPTION \\
850    \hline
851    
852    &\\
853     UFLUX    &   $Newton/m^2$  &    1  
854             &\begin{minipage}[t]{3in}
855              {Surface U-Wind Stress on the atmosphere}
856             \end{minipage}\\
857     VFLUX    &   $Newton/m^2$  &    1  
858             &\begin{minipage}[t]{3in}
859              {Surface V-Wind Stress on the atmosphere}
860             \end{minipage}\\
861     HFLUX    &   $Watts/m^2$  &    1  
862             &\begin{minipage}[t]{3in}
863              {Surface Flux of Sensible Heat}
864             \end{minipage}\\
865     EFLUX    &   $Watts/m^2$  &    1  
866             &\begin{minipage}[t]{3in}
867              {Surface Flux of Latent Heat}
868             \end{minipage}\\
869     QICE     &   $Watts/m^2$  &    1  
870             &\begin{minipage}[t]{3in}
871              {Heat Conduction through Sea-Ice}
872             \end{minipage}\\
873     RADLWG   &   $Watts/m^2$ &    1  
874             &\begin{minipage}[t]{3in}
875              {Net upward LW flux at the ground}
876             \end{minipage}\\
877     RADSWG   &   $Watts/m^2$  &    1
878             &\begin{minipage}[t]{3in}
879              {Net downward SW flux at the ground}
880             \end{minipage}\\
881     RI       &  $dimensionless$ &  Nrphys
882             &\begin{minipage}[t]{3in}
883              {Richardson Number}
884             \end{minipage}\\
885     CT       &  $dimensionless$ &  1
886             &\begin{minipage}[t]{3in}
887              {Surface Drag coefficient for T and Q}
888             \end{minipage}\\
889     CU       & $dimensionless$ &  1
890         &\begin{minipage}[t]{3in}
891          {Surface Drag coefficient for U and V}
892         \end{minipage}\\
893     ET       &  $m^2/sec$ &  Nrphys
894         &\begin{minipage}[t]{3in}
895          {Diffusivity coefficient for T and Q}
896         \end{minipage}\\
897     EU       &  $m^2/sec$ &  Nrphys
898         &\begin{minipage}[t]{3in}
899          {Diffusivity coefficient for U and V}
900         \end{minipage}\\
901     TURBU    &  $m/sec/day$ &  Nrphys
902         &\begin{minipage}[t]{3in}
903          {U-Momentum Changes due to Turbulence}
904         \end{minipage}\\
905     TURBV    &  $m/sec/day$ &  Nrphys
906         &\begin{minipage}[t]{3in}
907          {V-Momentum Changes due to Turbulence}
908         \end{minipage}\\
909     TURBT    &  $deg/day$ &  Nrphys
910         &\begin{minipage}[t]{3in}
911          {Temperature Changes due to Turbulence}
912         \end{minipage}\\
913     TURBQ    &  $g/kg/day$ &  Nrphys
914         &\begin{minipage}[t]{3in}
915          {Specific Humidity Changes due to Turbulence}
916         \end{minipage}\\
917     MOISTT   &   $deg/day$ &  Nrphys
918         &\begin{minipage}[t]{3in}
919          {Temperature Changes due to Moist Processes}
920         \end{minipage}\\
921     MOISTQ   &  $g/kg/day$ &  Nrphys
922         &\begin{minipage}[t]{3in}
923          {Specific Humidity Changes due to Moist Processes}
924         \end{minipage}\\
925     RADLW    &  $deg/day$ &  Nrphys
926         &\begin{minipage}[t]{3in}
927          {Net Longwave heating rate for each level}
928         \end{minipage}\\
929     RADSW    &  $deg/day$ &  Nrphys
930         &\begin{minipage}[t]{3in}
931          {Net Shortwave heating rate for each level}
932         \end{minipage}\\
933     PREACC   &  $mm/day$ &  1
934         &\begin{minipage}[t]{3in}
935          {Total Precipitation}
936         \end{minipage}\\
937     PRECON   &  $mm/day$ &  1
938         &\begin{minipage}[t]{3in}
939          {Convective Precipitation}
940         \end{minipage}\\
941     TUFLUX   &  $Newton/m^2$ &  Nrphys
942         &\begin{minipage}[t]{3in}
943          {Turbulent Flux of U-Momentum}
944         \end{minipage}\\
945     TVFLUX   &  $Newton/m^2$ &  Nrphys
946         &\begin{minipage}[t]{3in}
947          {Turbulent Flux of V-Momentum}
948         \end{minipage}\\
949     TTFLUX   &  $Watts/m^2$ &  Nrphys
950         &\begin{minipage}[t]{3in}
951          {Turbulent Flux of Sensible Heat}
952         \end{minipage}\\
953    \end{tabular}
954    
955    \newpage
956    \vspace*{\fill}
957    \begin{tabular}{llll}
958    \hline\hline
959     NAME & UNITS & LEVELS & DESCRIPTION \\
960    \hline
961    
962    &\\
963     TQFLUX   &  $Watts/m^2$ &  Nrphys
964         &\begin{minipage}[t]{3in}
965          {Turbulent Flux of Latent Heat}
966         \end{minipage}\\
967     CN       &  $dimensionless$ &  1
968         &\begin{minipage}[t]{3in}
969          {Neutral Drag Coefficient}
970         \end{minipage}\\
971     WINDS     &  $m/sec$ &  1
972         &\begin{minipage}[t]{3in}
973          {Surface Wind Speed}
974         \end{minipage}\\
975     DTSRF     &  $deg$ &  1
976         &\begin{minipage}[t]{3in}
977          {Air/Surface virtual temperature difference}
978         \end{minipage}\\
979     TG        &  $deg$ &  1
980         &\begin{minipage}[t]{3in}
981          {Ground temperature}
982         \end{minipage}\\
983     TS        &  $deg$ &  1
984         &\begin{minipage}[t]{3in}
985          {Surface air temperature (Adiabatic from lowest model layer)}
986         \end{minipage}\\
987     DTG       &  $deg$ &  1
988         &\begin{minipage}[t]{3in}
989          {Ground temperature adjustment}
990         \end{minipage}\\
991    
992     QG        &  $g/kg$ &  1
993         &\begin{minipage}[t]{3in}
994          {Ground specific humidity}
995         \end{minipage}\\
996     QS        &  $g/kg$ &  1
997         &\begin{minipage}[t]{3in}
998          {Saturation surface specific humidity}
999         \end{minipage}\\
1000     TGRLW    &    $deg$   &    1  
1001         &\begin{minipage}[t]{3in}
1002          {Instantaneous ground temperature used as input to the
1003           Longwave radiation subroutine}
1004         \end{minipage}\\
1005     ST4      &   $Watts/m^2$  &    1  
1006         &\begin{minipage}[t]{3in}
1007          {Upward Longwave flux at the ground ($\sigma T^4$)}
1008         \end{minipage}\\
1009     OLR      &   $Watts/m^2$  &    1  
1010         &\begin{minipage}[t]{3in}
1011          {Net upward Longwave flux at the top of the model}
1012         \end{minipage}\\
1013     OLRCLR   &   $Watts/m^2$  &    1  
1014         &\begin{minipage}[t]{3in}
1015          {Net upward clearsky Longwave flux at the top of the model}
1016         \end{minipage}\\
1017     LWGCLR   &   $Watts/m^2$  &    1  
1018         &\begin{minipage}[t]{3in}
1019          {Net upward clearsky Longwave flux at the ground}
1020         \end{minipage}\\
1021     LWCLR    &  $deg/day$ &  Nrphys
1022         &\begin{minipage}[t]{3in}
1023          {Net clearsky Longwave heating rate for each level}
1024         \end{minipage}\\
1025     TLW      &    $deg$   &  Nrphys
1026         &\begin{minipage}[t]{3in}
1027          {Instantaneous temperature used as input to the Longwave radiation
1028          subroutine}
1029         \end{minipage}\\
1030     SHLW     &    $g/g$   &  Nrphys
1031         &\begin{minipage}[t]{3in}
1032          {Instantaneous specific humidity used as input to the Longwave radiation
1033          subroutine}
1034         \end{minipage}\\
1035     OZLW     &    $g/g$   &  Nrphys
1036         &\begin{minipage}[t]{3in}
1037          {Instantaneous ozone used as input to the Longwave radiation
1038          subroutine}
1039         \end{minipage}\\
1040     CLMOLW   &    $0-1$   &  Nrphys
1041         &\begin{minipage}[t]{3in}
1042          {Maximum overlap cloud fraction used in the Longwave radiation
1043          subroutine}
1044         \end{minipage}\\
1045     CLDTOT   &    $0-1$   &  Nrphys
1046         &\begin{minipage}[t]{3in}
1047          {Total cloud fraction used in the Longwave and Shortwave radiation
1048          subroutines}
1049         \end{minipage}\\
1050     LWGDOWN  &    $Watts/m^2$   &  1
1051         &\begin{minipage}[t]{3in}
1052          {Downwelling Longwave radiation at the ground}
1053         \end{minipage}\\
1054     GWDT     &    $deg/day$ &  Nrphys
1055         &\begin{minipage}[t]{3in}
1056          {Temperature tendency due to Gravity Wave Drag}
1057         \end{minipage}\\
1058     RADSWT   &    $Watts/m^2$   &  1
1059         &\begin{minipage}[t]{3in}
1060          {Incident Shortwave radiation at the top of the atmosphere}
1061         \end{minipage}\\
1062     TAUCLD   &    $per 100 mb$   &  Nrphys
1063         &\begin{minipage}[t]{3in}
1064          {Counted Cloud Optical Depth (non-dimensional) per 100 mb}
1065         \end{minipage}\\
1066     TAUCLDC  &    $Number$   &  Nrphys
1067         &\begin{minipage}[t]{3in}
1068          {Cloud Optical Depth Counter}
1069         \end{minipage}\\
1070    \end{tabular}
1071    \vfill
1072    
1073    \newpage
1074    \vspace*{\fill}
1075    \begin{tabular}{llll}
1076    \hline\hline
1077     NAME & UNITS & LEVELS & DESCRIPTION \\
1078    \hline
1079    
1080    &\\
1081     CLDLOW   &    $0-1$   &  Nrphys
1082         &\begin{minipage}[t]{3in}
1083          {Low-Level ( 1000-700 hPa) Cloud Fraction  (0-1)}
1084         \end{minipage}\\
1085     EVAP     &    $mm/day$   &  1
1086         &\begin{minipage}[t]{3in}
1087          {Surface evaporation}
1088         \end{minipage}\\
1089     DPDT     &    $hPa/day$ &  1
1090         &\begin{minipage}[t]{3in}
1091          {Surface Pressure tendency}
1092         \end{minipage}\\
1093     UAVE     &    $m/sec$ &  Nrphys
1094         &\begin{minipage}[t]{3in}
1095          {Average U-Wind}
1096         \end{minipage}\\
1097     VAVE     &    $m/sec$ &  Nrphys
1098         &\begin{minipage}[t]{3in}
1099          {Average V-Wind}
1100         \end{minipage}\\
1101     TAVE     &    $deg$ &  Nrphys
1102         &\begin{minipage}[t]{3in}
1103          {Average Temperature}
1104         \end{minipage}\\
1105     QAVE     &    $g/kg$ &  Nrphys
1106         &\begin{minipage}[t]{3in}
1107          {Average Specific Humidity}
1108         \end{minipage}\\
1109     OMEGA    &    $hPa/day$ &  Nrphys
1110         &\begin{minipage}[t]{3in}
1111          {Vertical Velocity}
1112         \end{minipage}\\
1113     DUDT     &    $m/sec/day$ &  Nrphys
1114         &\begin{minipage}[t]{3in}
1115          {Total U-Wind tendency}
1116         \end{minipage}\\
1117     DVDT     &    $m/sec/day$ &  Nrphys
1118         &\begin{minipage}[t]{3in}
1119          {Total V-Wind tendency}
1120         \end{minipage}\\
1121     DTDT     &    $deg/day$ &  Nrphys
1122         &\begin{minipage}[t]{3in}
1123          {Total Temperature tendency}
1124         \end{minipage}\\
1125     DQDT     &    $g/kg/day$ &  Nrphys
1126         &\begin{minipage}[t]{3in}
1127          {Total Specific Humidity tendency}
1128         \end{minipage}\\
1129     VORT     &    $10^{-4}/sec$ &  Nrphys
1130         &\begin{minipage}[t]{3in}
1131          {Relative Vorticity}
1132         \end{minipage}\\
1133     DTLS     &    $deg/day$ &  Nrphys
1134         &\begin{minipage}[t]{3in}
1135          {Temperature tendency due to Stratiform Cloud Formation}
1136         \end{minipage}\\
1137     DQLS     &    $g/kg/day$ &  Nrphys
1138         &\begin{minipage}[t]{3in}
1139          {Specific Humidity tendency due to Stratiform Cloud Formation}
1140         \end{minipage}\\
1141     USTAR    &    $m/sec$ &  1
1142         &\begin{minipage}[t]{3in}
1143          {Surface USTAR wind}
1144         \end{minipage}\\
1145     Z0       &    $m$ &  1
1146         &\begin{minipage}[t]{3in}
1147          {Surface roughness}
1148         \end{minipage}\\
1149     FRQTRB   &    $0-1$ &  Nrphys-1
1150         &\begin{minipage}[t]{3in}
1151          {Frequency of Turbulence}
1152         \end{minipage}\\
1153     PBL      &    $mb$ &  1
1154         &\begin{minipage}[t]{3in}
1155          {Planetary Boundary Layer depth}
1156         \end{minipage}\\
1157     SWCLR    &  $deg/day$ &  Nrphys
1158         &\begin{minipage}[t]{3in}
1159          {Net clearsky Shortwave heating rate for each level}
1160         \end{minipage}\\
1161     OSR      &   $Watts/m^2$  &    1
1162         &\begin{minipage}[t]{3in}
1163          {Net downward Shortwave flux at the top of the model}
1164         \end{minipage}\\
1165     OSRCLR   &   $Watts/m^2$  &    1  
1166         &\begin{minipage}[t]{3in}
1167          {Net downward clearsky Shortwave flux at the top of the model}
1168         \end{minipage}\\
1169     CLDMAS   &   $kg / m^2$  &    Nrphys
1170         &\begin{minipage}[t]{3in}
1171          {Convective cloud mass flux}
1172         \end{minipage}\\
1173     UAVE     &   $m/sec$  &    Nrphys
1174         &\begin{minipage}[t]{3in}
1175          {Time-averaged $u-Wind$}
1176         \end{minipage}\\
1177    \end{tabular}
1178    \vfill
1179    
1180    \newpage
1181    \vspace*{\fill}
1182    \begin{tabular}{llll}
1183    \hline\hline
1184     NAME & UNITS & LEVELS & DESCRIPTION \\
1185    \hline
1186    
1187    &\\
1188     VAVE     &   $m/sec$  &    Nrphys
1189         &\begin{minipage}[t]{3in}
1190          {Time-averaged $v-Wind$}
1191         \end{minipage}\\
1192     TAVE     &   $deg$  &    Nrphys
1193         &\begin{minipage}[t]{3in}
1194          {Time-averaged $Temperature$}
1195         \end{minipage}\\
1196     QAVE     &   $g/g$  &    Nrphys
1197         &\begin{minipage}[t]{3in}
1198          {Time-averaged $Specific \, \, Humidity$}
1199         \end{minipage}\\
1200     RFT      &    $deg/day$ &  Nrphys
1201         &\begin{minipage}[t]{3in}
1202          {Temperature tendency due Rayleigh Friction}
1203         \end{minipage}\\
1204     PS       &   $mb$  &    1
1205         &\begin{minipage}[t]{3in}
1206          {Surface Pressure}
1207         \end{minipage}\\
1208     QQAVE    &   $(m/sec)^2$  &    Nrphys
1209         &\begin{minipage}[t]{3in}
1210          {Time-averaged $Turbulent Kinetic Energy$}
1211         \end{minipage}\\
1212     SWGCLR   &   $Watts/m^2$  &    1  
1213         &\begin{minipage}[t]{3in}
1214          {Net downward clearsky Shortwave flux at the ground}
1215         \end{minipage}\\
1216     PAVE     &   $mb$  &    1
1217         &\begin{minipage}[t]{3in}
1218          {Time-averaged Surface Pressure}
1219         \end{minipage}\\
1220     DIABU    & $m/sec/day$ &    Nrphys
1221         &\begin{minipage}[t]{3in}
1222          {Total Diabatic forcing on $u-Wind$}
1223         \end{minipage}\\
1224     DIABV    & $m/sec/day$ &    Nrphys
1225         &\begin{minipage}[t]{3in}
1226          {Total Diabatic forcing on $v-Wind$}
1227         \end{minipage}\\
1228     DIABT    & $deg/day$ &    Nrphys
1229         &\begin{minipage}[t]{3in}
1230          {Total Diabatic forcing on $Temperature$}
1231         \end{minipage}\\
1232     DIABQ    & $g/kg/day$ &    Nrphys
1233         &\begin{minipage}[t]{3in}
1234          {Total Diabatic forcing on $Specific \, \, Humidity$}
1235         \end{minipage}\\
1236     RFU      &    $m/sec/day$ &  Nrphys
1237         &\begin{minipage}[t]{3in}
1238          {U-Wind tendency due to Rayleigh Friction}
1239         \end{minipage}\\
1240     RFV      &    $m/sec/day$ &  Nrphys
1241         &\begin{minipage}[t]{3in}
1242          {V-Wind tendency due to Rayleigh Friction}
1243         \end{minipage}\\
1244     GWDU     &    $m/sec/day$ &  Nrphys
1245         &\begin{minipage}[t]{3in}
1246          {U-Wind tendency due to Gravity Wave Drag}
1247         \end{minipage}\\
1248     GWDU     &    $m/sec/day$ &  Nrphys
1249         &\begin{minipage}[t]{3in}
1250          {V-Wind tendency due to Gravity Wave Drag}
1251         \end{minipage}\\
1252     GWDUS    &    $N/m^2$ &  1
1253         &\begin{minipage}[t]{3in}
1254          {U-Wind Gravity Wave Drag Stress at Surface}
1255         \end{minipage}\\
1256     GWDVS    &    $N/m^2$ &  1
1257         &\begin{minipage}[t]{3in}
1258          {V-Wind Gravity Wave Drag Stress at Surface}
1259         \end{minipage}\\
1260     GWDUT    &    $N/m^2$ &  1
1261         &\begin{minipage}[t]{3in}
1262          {U-Wind Gravity Wave Drag Stress at Top}
1263         \end{minipage}\\
1264     GWDVT    &    $N/m^2$ &  1
1265         &\begin{minipage}[t]{3in}
1266          {V-Wind Gravity Wave Drag Stress at Top}
1267         \end{minipage}\\
1268     LZRAD    &    $mg/kg$ &  Nrphys
1269             &\begin{minipage}[t]{3in}
1270              {Estimated Cloud Liquid Water used in Radiation}
1271             \end{minipage}\\
1272    \end{tabular}
1273    \vfill
1274    
1275    \newpage
1276    \vspace*{\fill}
1277    \begin{tabular}{llll}
1278    \hline\hline
1279     NAME & UNITS & LEVELS & DESCRIPTION \\
1280    \hline
1281    
1282    &\\
1283     SLP      &   $mb$  &    1
1284             &\begin{minipage}[t]{3in}
1285              {Time-averaged Sea-level Pressure}
1286             \end{minipage}\\
1287     CLDFRC  & $0-1$ &    1
1288             &\begin{minipage}[t]{3in}
1289              {Total Cloud Fraction}
1290             \end{minipage}\\
1291     TPW     & $gm/cm^2$ &    1
1292             &\begin{minipage}[t]{3in}
1293              {Precipitable water}
1294             \end{minipage}\\
1295     U2M     & $m/sec$ &    1
1296             &\begin{minipage}[t]{3in}
1297              {U-Wind at 2 meters}
1298             \end{minipage}\\
1299     V2M     & $m/sec$ &    1
1300             &\begin{minipage}[t]{3in}
1301              {V-Wind at 2 meters}
1302             \end{minipage}\\
1303     T2M     & $deg$ &    1
1304             &\begin{minipage}[t]{3in}
1305              {Temperature at 2 meters}
1306             \end{minipage}\\
1307     Q2M     & $g/kg$ &    1
1308             &\begin{minipage}[t]{3in}
1309              {Specific Humidity at 2 meters}
1310             \end{minipage}\\
1311     U10M    & $m/sec$ &    1
1312             &\begin{minipage}[t]{3in}
1313              {U-Wind at 10 meters}
1314             \end{minipage}\\
1315     V10M    & $m/sec$ &    1
1316             &\begin{minipage}[t]{3in}
1317              {V-Wind at 10 meters}
1318             \end{minipage}\\
1319     T10M    & $deg$ &    1
1320             &\begin{minipage}[t]{3in}
1321              {Temperature at 10 meters}
1322             \end{minipage}\\
1323     Q10M    & $g/kg$ &    1
1324             &\begin{minipage}[t]{3in}
1325              {Specific Humidity at 10 meters}
1326             \end{minipage}\\
1327     DTRAIN  & $kg/m^2$ &    Nrphys
1328             &\begin{minipage}[t]{3in}
1329              {Detrainment Cloud Mass Flux}
1330             \end{minipage}\\
1331     QFILL   & $g/kg/day$ &    Nrphys
1332             &\begin{minipage}[t]{3in}
1333              {Filling of negative specific humidity}
1334             \end{minipage}\\
1335    \end{tabular}
1336    \vspace{1.5in}
1337    \vfill
1338    
1339    \newpage
1340    \vspace*{\fill}
1341    \begin{tabular}{llll}
1342    \hline\hline
1343     NAME & UNITS & LEVELS & DESCRIPTION \\
1344    \hline
1345    
1346    &\\
1347     DTCONV   & $deg/sec$ & Nr
1348             &\begin{minipage}[t]{3in}
1349              {Temp Change due to Convection}
1350             \end{minipage}\\
1351     DQCONV   & $g/kg/sec$ & Nr
1352             &\begin{minipage}[t]{3in}
1353              {Specific Humidity Change due to Convection}
1354             \end{minipage}\\
1355     RELHUM   & $percent$ & Nr
1356             &\begin{minipage}[t]{3in}
1357              {Relative Humidity}
1358             \end{minipage}\\
1359     PRECLS   & $g/m^2/sec$ & 1
1360             &\begin{minipage}[t]{3in}
1361              {Large Scale Precipitation}
1362             \end{minipage}\\
1363     ENPREC   & $J/g$ & 1
1364             &\begin{minipage}[t]{3in}
1365              {Energy of Precipitation (snow, rain Temp)}
1366             \end{minipage}\\
1367    \end{tabular}
1368    \vspace{1.5in}
1369    \vfill
1370    
1371    \newpage
1372    
1373    Fizhi Diagnostic Description:
1374    
1375    In this section we list and describe the diagnostic quantities available within the
1376    GCM.  The diagnostics are listed in the order that they appear in the
1377    Diagnostic Menu, Section \ref{sec:fizhi-diagnostics:menu}.
1378    In all cases, each diagnostic as currently archived on the output datasets
1379    is time-averaged over its diagnostic output frequency:
1380    
1381    \[
1382    {\bf DIAGNOSTIC} = {1 \over TTOT} \sum_{t=1}^{t=TTOT} diag(t)
1383    \]
1384    where $TTOT = {{\bf NQDIAG} \over \Delta t}$, {\bf NQDIAG} is the
1385    output frequency of the diagnostic, and $\Delta t$ is
1386    the timestep over which the diagnostic is updated.  
1387    
1388    { \underline {UFLUX} Surface Zonal Wind Stress on the Atmosphere ($Newton/m^2$) }
1389    
1390    The zonal wind stress is the turbulent flux of zonal momentum from
1391    the surface.
1392    \[
1393    {\bf UFLUX} =  - \rho C_D W_s u \hspace{1cm}where: \hspace{.2cm}C_D = C^2_u
1394    \]
1395    where $\rho$ = the atmospheric density at the surface, $C_{D}$ is the surface
1396    drag coefficient, $C_u$ is the dimensionless surface exchange coefficient for momentum
1397    (see diagnostic number 10), $W_s$ is the magnitude of the surface layer wind, and $u$ is
1398    the zonal wind in the lowest model layer.
1399    \\
1400    
1401    
1402    { \underline {VFLUX} Surface Meridional Wind Stress on the Atmosphere ($Newton/m^2$) }
1403    
1404    The meridional wind stress is the turbulent flux of meridional momentum from
1405    the surface.
1406    \[
1407    {\bf VFLUX} =  - \rho C_D W_s v \hspace{1cm}where: \hspace{.2cm}C_D = C^2_u
1408    \]
1409    where $\rho$ = the atmospheric density at the surface, $C_{D}$ is the surface
1410    drag coefficient, $C_u$ is the dimensionless surface exchange coefficient for momentum
1411    (see diagnostic number 10), $W_s$ is the magnitude of the surface layer wind, and $v$ is
1412    the meridional wind in the lowest model layer.
1413    \\
1414    
1415    { \underline {HFLUX} Surface Flux of Sensible Heat ($Watts/m^2$) }
1416    
1417    The turbulent flux of sensible heat from the surface to the atmosphere is a function of the
1418    gradient of virtual potential temperature and the eddy exchange coefficient:
1419    \[
1420    {\bf HFLUX} =  P^{\kappa}\rho c_{p} C_{H} W_s (\theta_{surface} - \theta_{Nrphys})
1421    \hspace{1cm}where: \hspace{.2cm}C_H = C_u C_t
1422    \]
1423    where $\rho$ = the atmospheric density at the surface, $c_{p}$ is the specific
1424    heat of air, $C_{H}$ is the dimensionless surface heat transfer coefficient, $W_s$ is the
1425    magnitude of the surface layer wind, $C_u$ is the dimensionless surface exchange coefficient
1426    for momentum (see diagnostic number 10), $C_t$ is the dimensionless surface exchange coefficient
1427    for heat and moisture (see diagnostic number 9), and $\theta$ is the potential temperature
1428    at the surface and at the bottom model level.
1429    \\
1430    
1431    
1432    { \underline {EFLUX} Surface Flux of Latent Heat ($Watts/m^2$) }
1433    
1434    The turbulent flux of latent heat from the surface to the atmosphere is a function of the
1435    gradient of moisture, the potential evapotranspiration fraction and the eddy exchange coefficient:
1436    \[
1437    {\bf EFLUX} =  \rho \beta L C_{H} W_s (q_{surface} - q_{Nrphys})
1438    \hspace{1cm}where: \hspace{.2cm}C_H = C_u C_t
1439    \]
1440    where $\rho$ = the atmospheric density at the surface, $\beta$ is the fraction of
1441    the potential evapotranspiration actually evaporated, L is the latent
1442    heat of evaporation, $C_{H}$ is the dimensionless surface heat transfer coefficient, $W_s$ is the
1443    magnitude of the surface layer wind, $C_u$ is the dimensionless surface exchange coefficient
1444    for momentum (see diagnostic number 10), $C_t$ is the dimensionless surface exchange coefficient
1445    for heat and moisture (see diagnostic number 9), and $q_{surface}$ and $q_{Nrphys}$ are the specific
1446    humidity at the surface and at the bottom model level, respectively.
1447    \\
1448    
1449    { \underline {QICE} Heat Conduction Through Sea Ice ($Watts/m^2$) }
1450    
1451    Over sea ice there is an additional source of energy at the surface due to the heat
1452    conduction from the relatively warm ocean through the sea ice. The heat conduction
1453    through sea ice represents an additional energy source term for the ground temperature equation.
1454    
1455    \[
1456    {\bf QICE} = {C_{ti} \over {H_i}} (T_i-T_g)
1457    \]
1458    
1459    where $C_{ti}$ is the thermal conductivity of ice, $H_i$ is the ice thickness, assumed to
1460    be $3 \hspace{.1cm} m$ where sea ice is present, $T_i$ is 273 degrees Kelvin, and
1461    $T_g$ is the temperature of the sea ice.
1462    
1463    NOTE: QICE is not available through model version 5.3, but is available in subsequent versions.
1464    \\
1465    
1466    
1467    { \underline {RADLWG} Net upward Longwave Flux at the surface ($Watts/m^2$)}
1468    
1469    \begin{eqnarray*}
1470    {\bf RADLWG} & =  & F_{LW,Nrphys+1}^{Net} \\
1471                 & =  & F_{LW,Nrphys+1}^\uparrow - F_{LW,Nrphys+1}^\downarrow
1472    \end{eqnarray*}
1473    \\
1474    where Nrphys+1 indicates the lowest model edge-level, or $p = p_{surf}$.
1475    $F_{LW}^\uparrow$ is
1476    the upward Longwave flux and $F_{LW}^\downarrow$ is the downward Longwave flux.
1477    \\
1478    
1479    { \underline {RADSWG} Net downard shortwave Flux at the surface ($Watts/m^2$)}
1480    
1481    \begin{eqnarray*}
1482    {\bf RADSWG} & =  & F_{SW,Nrphys+1}^{Net} \\
1483                 & =  & F_{SW,Nrphys+1}^\downarrow - F_{SW,Nrphys+1}^\uparrow
1484    \end{eqnarray*}
1485    \\
1486    where Nrphys+1 indicates the lowest model edge-level, or $p = p_{surf}$.
1487    $F_{SW}^\downarrow$ is
1488    the downward Shortwave flux and $F_{SW}^\uparrow$ is the upward Shortwave flux.
1489    \\
1490    
1491    
1492    \noindent
1493    { \underline {RI} Richardson Number} ($dimensionless$)
1494    
1495    \noindent
1496    The non-dimensional stability indicator is the ratio of the buoyancy to the shear:
1497    \[
1498    {\bf RI} = { { {g \over \theta_v} \pp {\theta_v}{z} } \over { (\pp{u}{z})^2 + (\pp{v}{z})^2 } }
1499     =  {  {c_p \pp{\theta_v}{z} \pp{P^ \kappa}{z} } \over { (\pp{u}{z})^2 + (\pp{v}{z})^2 } }
1500    \]
1501    \\
1502    where we used the hydrostatic equation:
1503    \[
1504    {\pp{\Phi}{P^ \kappa}} = c_p \theta_v
1505    \]
1506    Negative values indicate unstable buoyancy {\bf{AND}} shear, small positive values ($<0.4$)
1507    indicate dominantly unstable shear, and large positive values indicate dominantly stable
1508    stratification.
1509    \\
1510    
1511    \noindent
1512    { \underline {CT}  Surface Exchange Coefficient for Temperature and Moisture ($dimensionless$) }
1513    
1514    \noindent
1515    The surface exchange coefficient is obtained from the similarity functions for the stability
1516     dependant flux profile relationships:
1517    \[
1518    {\bf CT} = -{( {\overline{w^{\prime}\theta^{\prime}}}) \over {u_* \Delta \theta }} =
1519    -{( {\overline{w^{\prime}q^{\prime}}}) \over {u_* \Delta q }} =
1520    { k \over { (\psi_{h} + \psi_{g}) } }
1521    \]
1522    where $\psi_h$ is the surface layer non-dimensional temperature change and $\psi_g$ is the
1523    viscous sublayer non-dimensional temperature or moisture change:
1524    \[
1525    \psi_{h} = {\int_{\zeta_{0}}^{\zeta} {\phi_{h} \over \zeta} d \zeta} \hspace{1cm} and
1526    \hspace{1cm} \psi_{g} = { 0.55 (Pr^{2/3} - 0.2) \over \nu^{1/2} }
1527    (h_{0}u_{*} - h_{0_{ref}}u_{*_{ref}})^{1/2}
1528    \]
1529    and:
1530    $h_{0} = 30z_{0}$ with a maximum value over land of 0.01
1531    
1532    \noindent
1533    $\phi_h$ is the similarity function of $\zeta$, which expresses the stability dependance of
1534    the temperature and moisture gradients, specified differently for stable and unstable
1535    layers according to \cite{helfschu:95}. k is the Von Karman constant, $\zeta$ is the
1536    non-dimensional stability parameter, Pr is the Prandtl number for air, $\nu$ is the molecular
1537    viscosity, $z_{0}$ is the surface roughness length, $u_*$ is the surface stress velocity
1538    (see diagnostic number 67), and the subscript ref refers to a reference value.
1539    \\
1540    
1541    \noindent
1542    { \underline {CU}  Surface Exchange Coefficient for Momentum ($dimensionless$) }
1543    
1544    \noindent
1545    The surface exchange coefficient is obtained from the similarity functions for the stability
1546     dependant flux profile relationships:
1547    \[
1548    {\bf CU} = {u_* \over W_s} = { k \over \psi_{m} }
1549    \]
1550    where $\psi_m$ is the surface layer non-dimensional wind shear:
1551    \[
1552    \psi_{m} = {\int_{\zeta_{0}}^{\zeta} {\phi_{m} \over \zeta} d \zeta}
1553    \]
1554    \noindent
1555    $\phi_m$ is the similarity function of $\zeta$, which expresses the stability dependance of
1556    the temperature and moisture gradients, specified differently for stable and unstable layers
1557    according to \cite{helfschu:95}. k is the Von Karman constant, $\zeta$ is the
1558    non-dimensional stability parameter, $u_*$ is the surface stress velocity
1559    (see diagnostic number 67), and $W_s$ is the magnitude of the surface layer wind.
1560    \\
1561    
1562    \noindent
1563    { \underline {ET}  Diffusivity Coefficient for Temperature and Moisture ($m^2/sec$) }
1564    
1565    \noindent
1566    In the level 2.5 version of the Mellor-Yamada (1974) hierarchy, the turbulent heat or
1567    moisture flux for the atmosphere above the surface layer can be expressed as a turbulent
1568    diffusion coefficient $K_h$ times the negative of the gradient of potential temperature
1569    or moisture. In the \cite{helflab:88} adaptation of this closure, $K_h$
1570    takes the form:
1571    \[
1572    {\bf ET} = K_h = -{( {\overline{w^{\prime}\theta_v^{\prime}}}) \over {\pp{\theta_v}{z}} }
1573     = \left\{ \begin{array}{l@{\quad\mbox{for}\quad}l} q \, \ell \, S_H(G_M,G_H) & \mbox{decaying turbulence}
1574    \\ { q^2 \over {q_e} } \, \ell \, S_{H}(G_{M_e},G_{H_e}) & \mbox{growing turbulence} \end{array} \right.
1575    \]
1576    where $q$ is the turbulent velocity, or $\sqrt{2*turbulent \hspace{.2cm} kinetic \hspace{.2cm}
1577    energy}$, $q_e$ is the turbulence velocity derived from the more simple level 2.0 model,
1578    which describes equilibrium turbulence, $\ell$ is the master length scale related to the layer
1579    depth,
1580    $S_H$ is a function of $G_H$ and $G_M$, the dimensionless buoyancy and
1581    wind shear parameters, respectively, or a function of $G_{H_e}$ and $G_{M_e}$, the equilibrium
1582    dimensionless buoyancy and wind shear
1583    parameters.   Both $G_H$ and $G_M$, and their equilibrium values $G_{H_e}$ and $G_{M_e}$,
1584    are functions of the Richardson number.
1585    
1586    \noindent
1587    For the detailed equations and derivations of the modified level 2.5 closure scheme,
1588    see \cite{helflab:88}.
1589    
1590    \noindent
1591    In the surface layer, ${\bf {ET}}$ is the exchange coefficient for heat and moisture,
1592    in units of $m/sec$, given by:
1593    \[
1594    {\bf ET_{Nrphys}} =  C_t * u_* = C_H W_s
1595    \]
1596    \noindent
1597    where $C_t$ is the dimensionless exchange coefficient for heat and moisture from the
1598    surface layer similarity functions (see diagnostic number 9), $u_*$ is the surface
1599    friction velocity (see diagnostic number 67), $C_H$ is the heat transfer coefficient,
1600    and $W_s$ is the magnitude of the surface layer wind.
1601    \\
1602    
1603    \noindent
1604    { \underline {EU}  Diffusivity Coefficient for Momentum ($m^2/sec$) }
1605    
1606    \noindent  
1607    In the level 2.5 version of the Mellor-Yamada (1974) hierarchy, the turbulent heat
1608    momentum flux for the atmosphere above the surface layer can be expressed as a turbulent
1609    diffusion coefficient $K_m$ times the negative of the gradient of the u-wind.
1610    In the \cite{helflab:88} adaptation of this closure, $K_m$
1611    takes the form:
1612    \[
1613    {\bf EU} = K_m = -{( {\overline{u^{\prime}w^{\prime}}}) \over {\pp{U}{z}} }
1614     = \left\{ \begin{array}{l@{\quad\mbox{for}\quad}l} q \, \ell \, S_M(G_M,G_H) & \mbox{decaying turbulence}
1615    \\ { q^2 \over {q_e} } \, \ell \, S_{M}(G_{M_e},G_{H_e}) & \mbox{growing turbulence} \end{array} \right.
1616    \]
1617    \noindent
1618    where $q$ is the turbulent velocity, or $\sqrt{2*turbulent \hspace{.2cm} kinetic \hspace{.2cm}
1619    energy}$, $q_e$ is the turbulence velocity derived from the more simple level 2.0 model,
1620    which describes equilibrium turbulence, $\ell$ is the master length scale related to the layer
1621    depth,
1622    $S_M$ is a function of $G_H$ and $G_M$, the dimensionless buoyancy and
1623    wind shear parameters, respectively, or a function of $G_{H_e}$ and $G_{M_e}$, the equilibrium
1624    dimensionless buoyancy and wind shear
1625    parameters.   Both $G_H$ and $G_M$, and their equilibrium values $G_{H_e}$ and $G_{M_e}$,
1626    are functions of the Richardson number.
1627    
1628    \noindent
1629    For the detailed equations and derivations of the modified level 2.5 closure scheme,
1630    see \cite{helflab:88}.
1631    
1632    \noindent
1633    In the surface layer, ${\bf {EU}}$ is the exchange coefficient for momentum,
1634    in units of $m/sec$, given by:
1635    \[
1636    {\bf EU_{Nrphys}} = C_u * u_* = C_D W_s
1637    \]
1638    \noindent
1639    where $C_u$ is the dimensionless exchange coefficient for momentum from the surface layer
1640    similarity functions (see diagnostic number 10), $u_*$ is the surface friction velocity
1641    (see diagnostic number 67), $C_D$ is the surface drag coefficient, and $W_s$ is the
1642    magnitude of the surface layer wind.
1643    \\
1644    
1645    \noindent
1646    { \underline {TURBU}  Zonal U-Momentum changes due to Turbulence ($m/sec/day$) }
1647    
1648    \noindent
1649    The tendency of U-Momentum due to turbulence is written:
1650    \[
1651    {\bf TURBU} = {\pp{u}{t}}_{turb} = {\pp{}{z} }{(- \overline{u^{\prime}w^{\prime}})}
1652     = {\pp{}{z} }{(K_m \pp{u}{z})}
1653    \]
1654    
1655    \noindent
1656    The Helfand and Labraga level 2.5 scheme models the turbulent
1657    flux of u-momentum in terms of $K_m$, and the equation has the form of a diffusion
1658    equation.
1659    
1660    \noindent
1661    { \underline {TURBV}  Meridional V-Momentum changes due to Turbulence ($m/sec/day$) }
1662    
1663    \noindent
1664    The tendency of V-Momentum due to turbulence is written:
1665    \[
1666    {\bf TURBV} = {\pp{v}{t}}_{turb} = {\pp{}{z} }{(- \overline{v^{\prime}w^{\prime}})}
1667     = {\pp{}{z} }{(K_m \pp{v}{z})}
1668    \]
1669    
1670    \noindent
1671    The Helfand and Labraga level 2.5 scheme models the turbulent
1672    flux of v-momentum in terms of $K_m$, and the equation has the form of a diffusion
1673    equation.
1674    \\
1675    
1676    \noindent
1677    { \underline {TURBT}  Temperature changes due to Turbulence ($deg/day$) }
1678    
1679    \noindent
1680    The tendency of temperature due to turbulence is written:
1681    \[
1682    {\bf TURBT} = {\pp{T}{t}} = P^{\kappa}{\pp{\theta}{t}}_{turb} =
1683    P^{\kappa}{\pp{}{z} }{(- \overline{w^{\prime}\theta^{\prime}})}
1684     = P^{\kappa}{\pp{}{z} }{(K_h \pp{\theta_v}{z})}
1685    \]
1686    
1687    \noindent
1688    The Helfand and Labraga level 2.5 scheme models the turbulent
1689    flux of temperature in terms of $K_h$, and the equation has the form of a diffusion
1690    equation.
1691    \\
1692    
1693    \noindent
1694    { \underline {TURBQ}  Specific Humidity changes due to Turbulence ($g/kg/day$) }
1695    
1696    \noindent
1697    The tendency of specific humidity due to turbulence is written:
1698    \[
1699    {\bf TURBQ} = {\pp{q}{t}}_{turb} = {\pp{}{z} }{(- \overline{w^{\prime}q^{\prime}})}
1700     = {\pp{}{z} }{(K_h \pp{q}{z})}
1701    \]
1702    
1703    \noindent
1704    The Helfand and Labraga level 2.5 scheme models the turbulent
1705    flux of temperature in terms of $K_h$, and the equation has the form of a diffusion
1706    equation.
1707    \\
1708    
1709    \noindent
1710    { \underline {MOISTT} Temperature Changes Due to Moist Processes ($deg/day$) }
1711    
1712    \noindent
1713    \[
1714    {\bf MOISTT} = \left. {\pp{T}{t}}\right|_{c} + \left. {\pp{T}{t}} \right|_{ls}
1715    \]
1716    where:
1717    \[
1718    \left.{\pp{T}{t}}\right|_{c} = R \sum_i \left( \alpha { m_B \over c_p} \Gamma_s \right)_i
1719    \hspace{.4cm} and
1720    \hspace{.4cm} \left.{\pp{T}{t}}\right|_{ls} = {L \over c_p } (q^*-q)
1721    \]
1722    and
1723    \[
1724    \Gamma_s = g \eta \pp{s}{p}
1725    \]
1726    
1727    \noindent
1728    The subscript $c$ refers to convective processes, while the subscript $ls$ refers to large scale
1729    precipitation processes, or supersaturation rain.
1730    The summation refers to contributions from each cloud type called by RAS.  
1731    The dry static energy is given
1732    as $s$, the convective cloud base mass flux is given as $m_B$, and the cloud entrainment is
1733    given as $\eta$, which are explicitly defined in Section \ref{sec:fizhi:mc},
1734    the description of the convective parameterization.  The fractional adjustment, or relaxation
1735    parameter, for each cloud type is given as $\alpha$, while
1736    $R$ is the rain re-evaporation adjustment.
1737    \\
1738    
1739    \noindent
1740    { \underline {MOISTQ} Specific Humidity Changes Due to Moist Processes ($g/kg/day$) }
1741    
1742    \noindent
1743    \[
1744    {\bf MOISTQ} = \left. {\pp{q}{t}}\right|_{c} + \left. {\pp{q}{t}} \right|_{ls}
1745    \]
1746    where:
1747    \[
1748    \left.{\pp{q}{t}}\right|_{c} = R \sum_i \left( \alpha { m_B \over {L}}(\Gamma_h-\Gamma_s) \right)_i
1749    \hspace{.4cm} and
1750    \hspace{.4cm} \left.{\pp{q}{t}}\right|_{ls} = (q^*-q)
1751    \]
1752    and
1753    \[
1754    \Gamma_s = g \eta \pp{s}{p}\hspace{.4cm} and \hspace{.4cm}\Gamma_h = g \eta \pp{h}{p}
1755    \]
1756    \noindent
1757    The subscript $c$ refers to convective processes, while the subscript $ls$ refers to large scale
1758    precipitation processes, or supersaturation rain.
1759    The summation refers to contributions from each cloud type called by RAS.  
1760    The dry static energy is given as $s$,
1761    the moist static energy is given as $h$,
1762    the convective cloud base mass flux is given as $m_B$, and the cloud entrainment is
1763    given as $\eta$, which are explicitly defined in Section \ref{sec:fizhi:mc},
1764    the description of the convective parameterization.  The fractional adjustment, or relaxation
1765    parameter, for each cloud type is given as $\alpha$, while
1766    $R$ is the rain re-evaporation adjustment.
1767    \\
1768    
1769    \noindent
1770    { \underline {RADLW} Heating Rate due to Longwave Radiation ($deg/day$) }
1771    
1772    \noindent
1773    The net longwave heating rate is calculated as the vertical divergence of the
1774    net terrestrial radiative fluxes.
1775    Both the clear-sky and cloudy-sky longwave fluxes are computed within the
1776    longwave routine.
1777    The subroutine calculates the clear-sky flux, $F^{clearsky}_{LW}$, first.
1778    For a given cloud fraction,
1779    the clear line-of-sight probability $C(p,p^{\prime})$ is computed from the current level pressure $p$
1780    to the model top pressure, $p^{\prime} = p_{top}$, and the model surface pressure, $p^{\prime} = p_{surf}$,
1781    for the upward and downward radiative fluxes.
1782    (see Section \ref{sec:fizhi:radcloud}).
1783    The cloudy-sky flux is then obtained as:
1784      
1785    \noindent
1786    \[
1787    F_{LW} = C(p,p') \cdot F^{clearsky}_{LW},
1788    \]
1789    
1790    \noindent
1791    Finally, the net longwave heating rate is calculated as the vertical divergence of the
1792    net terrestrial radiative fluxes:
1793    \[
1794    \pp{\rho c_p T}{t} = - {\partial \over \partial z} F_{LW}^{NET} ,
1795    \]
1796    or
1797    \[
1798    {\bf RADLW} = \frac{g}{c_p \pi} {\partial \over \partial \sigma} F_{LW}^{NET} .
1799    \]
1800    
1801    \noindent
1802    where $g$ is the accelation due to gravity,
1803    $c_p$ is the heat capacity of air at constant pressure,
1804    and
1805    \[
1806    F_{LW}^{NET} = F_{LW}^\uparrow - F_{LW}^\downarrow
1807    \]
1808    \\
1809    
1810    
1811    \noindent
1812    { \underline {RADSW} Heating Rate due to Shortwave Radiation ($deg/day$) }
1813    
1814    \noindent
1815    The net Shortwave heating rate is calculated as the vertical divergence of the
1816    net solar radiative fluxes.
1817    The clear-sky and cloudy-sky shortwave fluxes are calculated separately.
1818    For the clear-sky case, the shortwave fluxes and heating rates are computed with
1819    both CLMO (maximum overlap cloud fraction) and
1820    CLRO (random overlap cloud fraction) set to zero (see Section \ref{sec:fizhi:radcloud}).
1821    The shortwave routine is then called a second time, for the cloudy-sky case, with the
1822    true time-averaged cloud fractions CLMO
1823    and CLRO being used.  In all cases, a normalized incident shortwave flux is used as
1824    input at the top of the atmosphere.
1825    
1826    \noindent
1827    The heating rate due to Shortwave Radiation under cloudy skies is defined as:
1828    \[
1829    \pp{\rho c_p T}{t} = - {\partial \over \partial z} F(cloudy)_{SW}^{NET} \cdot {\rm RADSWT},
1830    \]
1831    or
1832    \[
1833    {\bf RADSW} = \frac{g}{c_p \pi} {\partial \over \partial \sigma} F(cloudy)_{SW}^{NET}\cdot {\rm RADSWT} .
1834    \]
1835    
1836    \noindent
1837    where $g$ is the accelation due to gravity,
1838    $c_p$ is the heat capacity of air at constant pressure, RADSWT is the true incident
1839    shortwave radiation at the top of the atmosphere (See Diagnostic \#48), and
1840    \[
1841    F(cloudy)_{SW}^{Net} = F(cloudy)_{SW}^\uparrow - F(cloudy)_{SW}^\downarrow
1842    \]
1843    \\
1844    
1845    \noindent
1846    { \underline {PREACC} Total (Large-scale + Convective) Accumulated Precipition ($mm/day$) }
1847    
1848    \noindent
1849    For a change in specific humidity due to moist processes, $\Delta q_{moist}$,
1850    the vertical integral or total precipitable amount is given by:  
1851    \[
1852    {\bf PREACC} = \int_{surf}^{top} \rho \Delta q_{moist} dz = - \int_{surf}^{top} \Delta  q_{moist}
1853    {dp \over g} = {1 \over g} \int_0^1 \Delta q_{moist} dp
1854    \]
1855    \\
1856    
1857    \noindent
1858    A precipitation rate is defined as the vertically integrated moisture adjustment per Moist Processes
1859    time step, scaled to $mm/day$.
1860    \\
1861    
1862    \noindent
1863    { \underline {PRECON} Convective Precipition ($mm/day$) }
1864    
1865    \noindent
1866    For a change in specific humidity due to sub-grid scale cumulus convective processes, $\Delta q_{cum}$,
1867    the vertical integral or total precipitable amount is given by:  
1868    \[
1869    {\bf PRECON} = \int_{surf}^{top} \rho \Delta q_{cum} dz = - \int_{surf}^{top} \Delta  q_{cum}
1870    {dp \over g} = {1 \over g} \int_0^1 \Delta q_{cum} dp
1871    \]
1872    \\
1873    
1874    \noindent
1875    A precipitation rate is defined as the vertically integrated moisture adjustment per Moist Processes
1876    time step, scaled to $mm/day$.
1877    \\
1878    
1879    \noindent
1880    { \underline {TUFLUX}  Turbulent Flux of U-Momentum ($Newton/m^2$) }
1881    
1882    \noindent
1883    The turbulent flux of u-momentum is calculated for $diagnostic \hspace{.2cm} purposes
1884     \hspace{.2cm} only$ from the eddy coefficient for momentum:
1885    
1886    \[
1887    {\bf TUFLUX} =  {\rho } {(\overline{u^{\prime}w^{\prime}})} =  
1888    {\rho } {(- K_m \pp{U}{z})}
1889    \]
1890    
1891    \noindent
1892    where $\rho$ is the air density, and $K_m$ is the eddy coefficient.
1893    \\
1894    
1895    \noindent
1896    { \underline {TVFLUX}  Turbulent Flux of V-Momentum ($Newton/m^2$) }
1897    
1898    \noindent
1899    The turbulent flux of v-momentum is calculated for $diagnostic \hspace{.2cm} purposes
1900    \hspace{.2cm} only$ from the eddy coefficient for momentum:
1901    
1902    \[
1903    {\bf TVFLUX} =  {\rho } {(\overline{v^{\prime}w^{\prime}})} =
1904     {\rho } {(- K_m \pp{V}{z})}
1905    \]
1906    
1907    \noindent
1908    where $\rho$ is the air density, and $K_m$ is the eddy coefficient.
1909    \\
1910    
1911    
1912    \noindent
1913    { \underline {TTFLUX}  Turbulent Flux of Sensible Heat ($Watts/m^2$) }
1914    
1915    \noindent
1916    The turbulent flux of sensible heat is calculated for $diagnostic \hspace{.2cm} purposes
1917    \hspace{.2cm} only$ from the eddy coefficient for heat and moisture:
1918    
1919    \noindent
1920    \[
1921    {\bf TTFLUX} = c_p {\rho }  
1922    P^{\kappa}{(\overline{w^{\prime}\theta^{\prime}})}
1923     = c_p  {\rho } P^{\kappa}{(- K_h \pp{\theta_v}{z})}
1924    \]
1925    
1926    \noindent
1927    where $\rho$ is the air density, and $K_h$ is the eddy coefficient.
1928    \\
1929    
1930    
1931    \noindent
1932    { \underline {TQFLUX}  Turbulent Flux of Latent Heat ($Watts/m^2$) }
1933    
1934    \noindent
1935    The turbulent flux of latent heat is calculated for $diagnostic \hspace{.2cm} purposes
1936    \hspace{.2cm} only$ from the eddy coefficient for heat and moisture:
1937    
1938    \noindent
1939    \[
1940    {\bf TQFLUX} = {L {\rho } (\overline{w^{\prime}q^{\prime}})} =
1941    {L {\rho }(- K_h \pp{q}{z})}
1942    \]
1943    
1944    \noindent
1945    where $\rho$ is the air density, and $K_h$ is the eddy coefficient.
1946    \\
1947    
1948    
1949    \noindent
1950    { \underline {CN}  Neutral Drag Coefficient ($dimensionless$) }
1951    
1952    \noindent
1953    The drag coefficient for momentum obtained by assuming a neutrally stable surface layer:
1954    \[
1955    {\bf CN} = { k \over { \ln({h \over {z_0}})} }
1956    \]
1957    
1958    \noindent
1959    where $k$ is the Von Karman constant, $h$ is the height of the surface layer, and
1960    $z_0$ is the surface roughness.
1961    
1962    \noindent
1963    NOTE: CN is not available through model version 5.3, but is available in subsequent
1964    versions.
1965    \\
1966    
1967    \noindent
1968    { \underline {WINDS}  Surface Wind Speed ($meter/sec$) }
1969    
1970    \noindent
1971    The surface wind speed is calculated for the last internal turbulence time step:
1972    \[
1973    {\bf WINDS} = \sqrt{u_{Nrphys}^2 + v_{Nrphys}^2}
1974    \]
1975    
1976    \noindent
1977    where the subscript $Nrphys$ refers to the lowest model level.
1978    \\
1979    
1980    \noindent
1981    { \underline {DTSRF}  Air/Surface Virtual Temperature Difference ($deg \hspace{.1cm} K$) }
1982    
1983    \noindent
1984    The air/surface virtual temperature difference measures the stability of the surface layer:
1985    \[
1986    {\bf DTSRF} = (\theta_{v{Nrphys+1}} - \theta{v_{Nrphys}}) P^{\kappa}_{surf}
1987    \]
1988    \noindent
1989    where
1990    \[
1991    \theta_{v{Nrphys+1}} = { T_g \over {P^{\kappa}_{surf}} } (1 + .609 q_{Nrphys+1}) \hspace{1cm}
1992    and \hspace{1cm} q_{Nrphys+1} = q_{Nrphys} + \beta(q^*(T_g,P_s) - q_{Nrphys})
1993    \]
1994    
1995    \noindent
1996    $\beta$ is the surface potential evapotranspiration coefficient ($\beta=1$ over oceans),
1997    $q^*(T_g,P_s)$ is the saturation specific humidity at the ground temperature
1998    and surface pressure, level $Nrphys$ refers to the lowest model level and level $Nrphys+1$
1999    refers to the surface.
2000    \\
2001    
2002    
2003    \noindent
2004    { \underline {TG}  Ground Temperature ($deg \hspace{.1cm} K$) }
2005    
2006    \noindent
2007    The ground temperature equation is solved as part of the turbulence package
2008    using a backward implicit time differencing scheme:
2009    \[
2010    {\bf TG} \hspace{.1cm} is \hspace{.1cm} obtained \hspace{.1cm} from: \hspace{.1cm}
2011    C_g\pp{T_g}{t} = R_{sw} - R_{lw} + Q_{ice} - H - LE
2012    \]
2013    
2014    \noindent
2015    where $R_{sw}$ is the net surface downward shortwave radiative flux, $R_{lw}$ is the
2016    net surface upward longwave radiative flux, $Q_{ice}$ is the heat conduction through
2017    sea ice, $H$ is the upward sensible heat flux, $LE$ is the upward latent heat
2018    flux, and $C_g$ is the total heat capacity of the ground.
2019    $C_g$ is obtained by solving a heat diffusion equation
2020    for the penetration of the diurnal cycle into the ground (\cite{black:77}), and is given by:
2021    \[
2022    C_g = \sqrt{ {\lambda C_s \over {2 \omega} } } = \sqrt{(0.386 + 0.536W + 0.15W^2)2x10^{-3}
2023    { 86400. \over {2 \pi} } } \, \, .
2024    \]
2025    \noindent
2026    Here, the thermal conductivity, $\lambda$, is equal to $2x10^{-3}$ ${ly\over{ sec}}
2027    {cm \over {^oK}}$,
2028    the angular velocity of the earth, $\omega$, is written as $86400$ $sec/day$ divided
2029    by $2 \pi$ $radians/
2030    day$, and the expression for $C_s$, the heat capacity per unit volume at the surface,
2031    is a function of the ground wetness, $W$.
2032    \\
2033    
2034    \noindent
2035    { \underline {TS}  Surface Temperature ($deg \hspace{.1cm} K$) }
2036    
2037    \noindent
2038    The surface temperature estimate is made by assuming that the model's lowest
2039    layer is well-mixed, and therefore that $\theta$ is constant in that layer.
2040    The surface temperature is therefore:
2041    \[
2042    {\bf TS} = \theta_{Nrphys} P^{\kappa}_{surf}
2043    \]
2044    \\
2045    
2046    \noindent
2047    { \underline {DTG}  Surface Temperature Adjustment ($deg \hspace{.1cm} K$) }
2048    
2049    \noindent
2050    The change in surface temperature from one turbulence time step to the next, solved
2051    using the Ground Temperature Equation (see diagnostic number 30) is calculated:
2052    \[
2053    {\bf DTG} = {T_g}^{n} - {T_g}^{n-1}
2054    \]
2055    
2056    \noindent
2057    where superscript $n$ refers to the new, updated time level, and the superscript $n-1$
2058    refers to the value at the previous turbulence time level.
2059    \\
2060    
2061    \noindent
2062    { \underline {QG}  Ground Specific Humidity ($g/kg$) }
2063    
2064    \noindent
2065    The ground specific humidity is obtained by interpolating between the specific
2066    humidity at the lowest model level and the specific humidity of a saturated ground.
2067    The interpolation is performed using the potential evapotranspiration function:
2068    \[
2069    {\bf QG} = q_{Nrphys+1} = q_{Nrphys} + \beta(q^*(T_g,P_s) - q_{Nrphys})
2070    \]
2071    
2072    \noindent
2073    where $\beta$ is the surface potential evapotranspiration coefficient ($\beta=1$ over oceans),
2074    and $q^*(T_g,P_s)$ is the saturation specific humidity at the ground temperature and surface
2075    pressure.
2076    \\
2077    
2078    \noindent
2079    { \underline {QS}  Saturation Surface Specific Humidity ($g/kg$) }
2080    
2081    \noindent
2082    The surface saturation specific humidity is the saturation specific humidity at
2083    the ground temprature and surface pressure:
2084    \[
2085    {\bf QS} = q^*(T_g,P_s)
2086    \]
2087    \\
2088    
2089    \noindent
2090    { \underline {TGRLW} Instantaneous ground temperature used as input to the Longwave
2091     radiation subroutine (deg)}
2092    \[
2093    {\bf TGRLW}  = T_g(\lambda , \phi ,n)
2094    \]
2095    \noindent
2096    where $T_g$ is the model ground temperature at the current time step $n$.
2097    \\
2098    
2099    
2100    \noindent
2101    { \underline {ST4} Upward Longwave flux at the surface ($Watts/m^2$) }
2102    \[
2103    {\bf ST4} = \sigma T^4
2104    \]
2105    \noindent
2106    where $\sigma$ is the Stefan-Boltzmann constant and T is the temperature.
2107    \\
2108    
2109    \noindent
2110    { \underline {OLR} Net upward Longwave flux at $p=p_{top}$ ($Watts/m^2$) }
2111    \[
2112    {\bf OLR}  =  F_{LW,top}^{NET}
2113    \]
2114    \noindent
2115    where top indicates the top of the first model layer.
2116    In the GCM, $p_{top}$ = 0.0 mb.
2117    \\
2118    
2119    
2120    \noindent
2121    { \underline {OLRCLR} Net upward clearsky Longwave flux at $p=p_{top}$ ($Watts/m^2$) }
2122    \[
2123    {\bf OLRCLR}  =  F(clearsky)_{LW,top}^{NET}
2124    \]
2125    \noindent
2126    where top indicates the top of the first model layer.
2127    In the GCM, $p_{top}$ = 0.0 mb.
2128    \\
2129    
2130    \noindent
2131    { \underline {LWGCLR} Net upward clearsky Longwave flux at the surface ($Watts/m^2$) }
2132    
2133    \noindent
2134    \begin{eqnarray*}
2135    {\bf LWGCLR} & =  & F(clearsky)_{LW,Nrphys+1}^{Net} \\
2136                 & =  & F(clearsky)_{LW,Nrphys+1}^\uparrow - F(clearsky)_{LW,Nrphys+1}^\downarrow
2137    \end{eqnarray*}
2138    where Nrphys+1 indicates the lowest model edge-level, or $p = p_{surf}$.
2139    $F(clearsky)_{LW}^\uparrow$ is
2140    the upward clearsky Longwave flux and the $F(clearsky)_{LW}^\downarrow$ is the downward clearsky Longwave flux.
2141    \\
2142    
2143    \noindent
2144    { \underline {LWCLR} Heating Rate due to Clearsky Longwave Radiation ($deg/day$) }
2145    
2146    \noindent
2147    The net longwave heating rate is calculated as the vertical divergence of the
2148    net terrestrial radiative fluxes.
2149    Both the clear-sky and cloudy-sky longwave fluxes are computed within the
2150    longwave routine.
2151    The subroutine calculates the clear-sky flux, $F^{clearsky}_{LW}$, first.
2152    For a given cloud fraction,
2153    the clear line-of-sight probability $C(p,p^{\prime})$ is computed from the current level pressure $p$
2154    to the model top pressure, $p^{\prime} = p_{top}$, and the model surface pressure, $p^{\prime} = p_{surf}$,
2155    for the upward and downward radiative fluxes.
2156    (see Section \ref{sec:fizhi:radcloud}).
2157    The cloudy-sky flux is then obtained as:
2158      
2159    \noindent
2160    \[
2161    F_{LW} = C(p,p') \cdot F^{clearsky}_{LW},
2162    \]
2163    
2164    \noindent
2165    Thus, {\bf LWCLR} is defined as the net longwave heating rate due to the
2166    vertical divergence of the
2167    clear-sky longwave radiative flux:
2168    \[
2169    \pp{\rho c_p T}{t}_{clearsky} = - {\partial \over \partial z} F(clearsky)_{LW}^{NET} ,
2170    \]
2171    or
2172    \[
2173    {\bf LWCLR} = \frac{g}{c_p \pi} {\partial \over \partial \sigma} F(clearsky)_{LW}^{NET} .
2174    \]
2175    
2176    \noindent
2177    where $g$ is the accelation due to gravity,
2178    $c_p$ is the heat capacity of air at constant pressure,
2179    and
2180    \[
2181    F(clearsky)_{LW}^{Net} = F(clearsky)_{LW}^\uparrow - F(clearsky)_{LW}^\downarrow
2182    \]
2183    \\
2184    
2185    
2186    \noindent
2187    { \underline {TLW} Instantaneous temperature used as input to the Longwave
2188     radiation subroutine (deg)}
2189    \[
2190    {\bf TLW}  = T(\lambda , \phi ,level, n)
2191    \]
2192    \noindent
2193    where $T$ is the model temperature at the current time step $n$.
2194    \\
2195    
2196    
2197    \noindent
2198    { \underline {SHLW} Instantaneous specific humidity used as input to
2199     the Longwave radiation subroutine (kg/kg)}
2200    \[
2201    {\bf SHLW}  = q(\lambda , \phi , level , n)
2202    \]
2203    \noindent
2204    where $q$ is the model specific humidity at the current time step $n$.
2205    \\
2206    
2207    
2208    \noindent
2209    { \underline {OZLW} Instantaneous ozone used as input to
2210     the Longwave radiation subroutine (kg/kg)}
2211    \[
2212    {\bf OZLW}  = {\rm OZ}(\lambda , \phi , level , n)
2213    \]
2214    \noindent
2215    where $\rm OZ$ is the interpolated ozone data set from the climatological monthly
2216    mean zonally averaged ozone data set.
2217    \\
2218    
2219    
2220    \noindent
2221    { \underline {CLMOLW} Maximum Overlap cloud fraction used in LW Radiation ($0-1$) }
2222    
2223    \noindent
2224    {\bf CLMOLW} is the time-averaged maximum overlap cloud fraction that has been filled by the Relaxed
2225    Arakawa/Schubert Convection scheme and will be used in the Longwave Radiation algorithm.  These are
2226    convective clouds whose radiative characteristics are assumed to be correlated in the vertical.
2227    For a complete description of cloud/radiative interactions, see Section \ref{sec:fizhi:radcloud}.
2228    \[
2229    {\bf CLMOLW} = CLMO_{RAS,LW}(\lambda, \phi,  level )
2230    \]
2231    \\
2232    
2233    
2234    { \underline {CLDTOT} Total cloud fraction used in LW and SW Radiation ($0-1$) }
2235    
2236    {\bf CLDTOT} is the time-averaged total cloud fraction that has been filled by the Relaxed
2237    Arakawa/Schubert and Large-scale Convection schemes and will be used in the Longwave and Shortwave
2238    Radiation packages.
2239    For a complete description of cloud/radiative interactions, see Section \ref{sec:fizhi:radcloud}.
2240    \[
2241    {\bf CLDTOT} = F_{RAS} + F_{LS}
2242    \]
2243    \\
2244    where $F_{RAS}$ is the time-averaged cloud fraction due to sub-grid scale convection, and $F_{LS}$ is the
2245    time-averaged cloud fraction due to precipitating and non-precipitating large-scale moist processes.
2246    \\
2247    
2248    
2249    \noindent
2250    { \underline {CLMOSW} Maximum Overlap cloud fraction used in SW Radiation ($0-1$) }
2251    
2252    \noindent
2253    {\bf CLMOSW} is the time-averaged maximum overlap cloud fraction that has been filled by the Relaxed
2254    Arakawa/Schubert Convection scheme and will be used in the Shortwave Radiation algorithm.  These are
2255    convective clouds whose radiative characteristics are assumed to be correlated in the vertical.
2256    For a complete description of cloud/radiative interactions, see Section \ref{sec:fizhi:radcloud}.
2257    \[
2258    {\bf CLMOSW} = CLMO_{RAS,SW}(\lambda, \phi,  level )
2259    \]
2260    \\
2261    
2262    \noindent
2263    { \underline {CLROSW} Random Overlap cloud fraction used in SW Radiation ($0-1$) }
2264    
2265    \noindent
2266    {\bf CLROSW} is the time-averaged random overlap cloud fraction that has been filled by the Relaxed
2267    Arakawa/Schubert and Large-scale Convection schemes and will be used in the Shortwave
2268    Radiation algorithm.  These are
2269    convective and large-scale clouds whose radiative characteristics are not
2270    assumed to be correlated in the vertical.
2271    For a complete description of cloud/radiative interactions, see Section \ref{sec:fizhi:radcloud}.
2272    \[
2273    {\bf CLROSW} = CLRO_{RAS,Large Scale,SW}(\lambda, \phi,  level )
2274    \]
2275    \\
2276    
2277    \noindent
2278    { \underline {RADSWT} Incident Shortwave radiation at the top of the atmosphere ($Watts/m^2$) }
2279    \[
2280    {\bf RADSWT} = {\frac{S_0}{R_a^2}} \cdot cos \phi_z
2281    \]
2282    \noindent
2283    where $S_0$, is the extra-terrestial solar contant,
2284    $R_a$ is the earth-sun distance in Astronomical Units,
2285    and $cos \phi_z$ is the cosine of the zenith angle.
2286    It should be noted that {\bf RADSWT}, as well as
2287    {\bf OSR} and {\bf OSRCLR},
2288    are calculated at the top of the atmosphere (p=0 mb).  However, the
2289    {\bf OLR} and {\bf OLRCLR} diagnostics are currently
2290    calculated at $p= p_{top}$ (0.0 mb for the GCM).
2291    \\
2292      
2293    \noindent
2294    { \underline {EVAP}  Surface Evaporation ($mm/day$) }
2295    
2296    \noindent
2297    The surface evaporation is a function of the gradient of moisture, the potential
2298    evapotranspiration fraction and the eddy exchange coefficient:
2299    \[
2300    {\bf EVAP} =  \rho \beta K_{h} (q_{surface} - q_{Nrphys})
2301    \]
2302    where $\rho$ = the atmospheric density at the surface, $\beta$ is the fraction of
2303    the potential evapotranspiration actually evaporated ($\beta=1$ over oceans), $K_{h}$ is the
2304    turbulent eddy exchange coefficient for heat and moisture at the surface in $m/sec$ and
2305    $q{surface}$ and $q_{Nrphys}$ are the specific humidity at the surface (see diagnostic
2306    number 34) and at the bottom model level, respectively.
2307    \\
2308    
2309    \noindent
2310    { \underline {DUDT} Total Zonal U-Wind Tendency  ($m/sec/day$) }
2311    
2312    \noindent
2313    {\bf DUDT} is the total time-tendency of the Zonal U-Wind due to Hydrodynamic, Diabatic,
2314    and Analysis forcing.
2315    \[
2316    {\bf DUDT} = \pp{u}{t}_{Dynamics} + \pp{u}{t}_{Moist} + \pp{u}{t}_{Turbulence} + \pp{u}{t}_{Analysis}
2317    \]
2318    \\
2319    
2320    \noindent
2321    { \underline {DVDT} Total Zonal V-Wind Tendency  ($m/sec/day$) }
2322    
2323    \noindent
2324    {\bf DVDT} is the total time-tendency of the Meridional V-Wind due to Hydrodynamic, Diabatic,
2325    and Analysis forcing.
2326    \[
2327    {\bf DVDT} = \pp{v}{t}_{Dynamics} + \pp{v}{t}_{Moist} + \pp{v}{t}_{Turbulence} + \pp{v}{t}_{Analysis}
2328    \]
2329    \\
2330    
2331    \noindent
2332    { \underline {DTDT} Total Temperature Tendency  ($deg/day$) }
2333    
2334    \noindent
2335    {\bf DTDT} is the total time-tendency of Temperature due to Hydrodynamic, Diabatic,
2336    and Analysis forcing.
2337    \begin{eqnarray*}
2338    {\bf DTDT} & = & \pp{T}{t}_{Dynamics} + \pp{T}{t}_{Moist Processes} + \pp{T}{t}_{Shortwave Radiation} \\
2339               & + & \pp{T}{t}_{Longwave Radiation} + \pp{T}{t}_{Turbulence} + \pp{T}{t}_{Analysis}
2340    \end{eqnarray*}
2341    \\
2342    
2343    \noindent
2344    { \underline {DQDT} Total Specific Humidity Tendency  ($g/kg/day$) }
2345    
2346    \noindent
2347    {\bf DQDT} is the total time-tendency of Specific Humidity due to Hydrodynamic, Diabatic,
2348    and Analysis forcing.
2349    \[
2350    {\bf DQDT} = \pp{q}{t}_{Dynamics} + \pp{q}{t}_{Moist Processes}
2351    + \pp{q}{t}_{Turbulence} + \pp{q}{t}_{Analysis}
2352    \]
2353    \\
2354      
2355    \noindent
2356    { \underline {USTAR}  Surface-Stress Velocity ($m/sec$) }
2357    
2358    \noindent
2359    The surface stress velocity, or the friction velocity, is the wind speed at
2360    the surface layer top impeded by the surface drag:
2361    \[
2362    {\bf USTAR} = C_uW_s \hspace{1cm}where: \hspace{.2cm}
2363    C_u = {k \over {\psi_m} }
2364    \]
2365    
2366    \noindent
2367    $C_u$ is the non-dimensional surface drag coefficient (see diagnostic
2368    number 10), and $W_s$ is the surface wind speed (see diagnostic number 28).
2369    
2370    \noindent
2371    { \underline {Z0}  Surface Roughness Length ($m$) }
2372    
2373    \noindent
2374    Over the land surface, the surface roughness length is interpolated to the local
2375    time from the monthly mean data of \cite{dorsell:89}. Over the ocean,
2376    the roughness length is a function of the surface-stress velocity, $u_*$.
2377    \[
2378    {\bf Z0} = c_1u^3_* + c_2u^2_* + c_3u_* + c_4 + {c_5 \over {u_*}}
2379    \]
2380    
2381    \noindent
2382    where the constants are chosen to interpolate between the reciprocal relation of
2383    \cite{kondo:75} for weak winds, and the piecewise linear relation of \cite{larpond:81}
2384    for moderate to large winds.
2385    \\
2386    
2387    \noindent
2388    { \underline {FRQTRB}  Frequency of Turbulence ($0-1$) }
2389    
2390    \noindent
2391    The fraction of time when turbulence is present is defined as the fraction of
2392    time when the turbulent kinetic energy exceeds some minimum value, defined here
2393    to be $0.005 \hspace{.1cm}m^2/sec^2$. When this criterion is met, a counter is
2394    incremented. The fraction over the averaging interval is reported.
2395    \\
2396    
2397    \noindent
2398    { \underline {PBL}  Planetary Boundary Layer Depth ($mb$) }
2399    
2400    \noindent
2401    The depth of the PBL is defined by the turbulence parameterization to be the
2402    depth at which the turbulent kinetic energy reduces to ten percent of its surface
2403    value.
2404    
2405    \[
2406    {\bf PBL} = P_{PBL} - P_{surface}
2407    \]
2408    
2409    \noindent
2410    where $P_{PBL}$ is the pressure in $mb$ at which the turbulent kinetic energy
2411    reaches one tenth of its surface value, and $P_s$ is the surface pressure.
2412    \\
2413    
2414    \noindent
2415    { \underline {SWCLR} Clear sky Heating Rate due to Shortwave Radiation ($deg/day$) }
2416    
2417    \noindent
2418    The net Shortwave heating rate is calculated as the vertical divergence of the
2419    net solar radiative fluxes.
2420    The clear-sky and cloudy-sky shortwave fluxes are calculated separately.
2421    For the clear-sky case, the shortwave fluxes and heating rates are computed with
2422    both CLMO (maximum overlap cloud fraction) and
2423    CLRO (random overlap cloud fraction) set to zero (see Section \ref{sec:fizhi:radcloud}).
2424    The shortwave routine is then called a second time, for the cloudy-sky case, with the
2425    true time-averaged cloud fractions CLMO
2426    and CLRO being used.  In all cases, a normalized incident shortwave flux is used as
2427    input at the top of the atmosphere.
2428    
2429    \noindent
2430    The heating rate due to Shortwave Radiation under clear skies is defined as:
2431    \[
2432    \pp{\rho c_p T}{t} = - {\partial \over \partial z} F(clear)_{SW}^{NET} \cdot {\rm RADSWT},
2433    \]
2434    or
2435    \[
2436    {\bf SWCLR} = \frac{g}{c_p } {\partial \over \partial p} F(clear)_{SW}^{NET}\cdot {\rm RADSWT} .
2437    \]
2438    
2439    \noindent
2440    where $g$ is the accelation due to gravity,
2441    $c_p$ is the heat capacity of air at constant pressure, RADSWT is the true incident
2442    shortwave radiation at the top of the atmosphere (See Diagnostic \#48), and
2443    \[
2444    F(clear)_{SW}^{Net} = F(clear)_{SW}^\uparrow - F(clear)_{SW}^\downarrow
2445    \]
2446    \\
2447    
2448    \noindent
2449    { \underline {OSR} Net upward Shortwave flux at the top of the model ($Watts/m^2$) }
2450    \[
2451    {\bf OSR}  =  F_{SW,top}^{NET}
2452    \]                                                                                      
2453    \noindent
2454    where top indicates the top of the first model layer used in the shortwave radiation
2455    routine.
2456    In the GCM, $p_{SW_{top}}$ = 0 mb.
2457    \\
2458    
2459    \noindent
2460    { \underline {OSRCLR} Net upward clearsky Shortwave flux at the top of the model ($Watts/m^2$) }
2461    \[
2462    {\bf OSRCLR}  =  F(clearsky)_{SW,top}^{NET}
2463    \]
2464    \noindent
2465    where top indicates the top of the first model layer used in the shortwave radiation
2466    routine.
2467    In the GCM, $p_{SW_{top}}$ = 0 mb.
2468    \\
2469    
2470    
2471    \noindent
2472    { \underline {CLDMAS} Convective Cloud Mass Flux ($kg/m^2$) }
2473    
2474    \noindent
2475    The amount of cloud mass moved per RAS timestep from all convective clouds is written:
2476    \[
2477    {\bf CLDMAS} = \eta m_B
2478    \]
2479    where $\eta$ is the entrainment, normalized by the cloud base mass flux, and $m_B$ is
2480    the cloud base mass flux. $m_B$ and $\eta$ are defined explicitly in Section \ref{sec:fizhi:mc}, the
2481    description of the convective parameterization.
2482    \\
2483    
2484    
2485    
2486    \noindent
2487    { \underline {UAVE} Time-Averaged Zonal U-Wind ($m/sec$) }
2488    
2489    \noindent
2490    The diagnostic {\bf UAVE} is simply the time-averaged Zonal U-Wind over
2491    the {\bf NUAVE} output frequency.  This is contrasted to the instantaneous
2492    Zonal U-Wind which is archived on the Prognostic Output data stream.
2493    \[
2494    {\bf UAVE} = u(\lambda, \phi, level , t)
2495    \]
2496    \\
2497    Note, {\bf UAVE} is computed and stored on the staggered C-grid.
2498    \\
2499    
2500    \noindent
2501    { \underline {VAVE} Time-Averaged Meridional V-Wind ($m/sec$) }
2502    
2503    \noindent
2504    The diagnostic {\bf VAVE} is simply the time-averaged Meridional V-Wind over
2505    the {\bf NVAVE} output frequency.  This is contrasted to the instantaneous
2506    Meridional V-Wind which is archived on the Prognostic Output data stream.
2507    \[
2508    {\bf VAVE} = v(\lambda, \phi, level , t)
2509    \]
2510    \\
2511    Note, {\bf VAVE} is computed and stored on the staggered C-grid.
2512    \\
2513    
2514    \noindent
2515    { \underline {TAVE} Time-Averaged Temperature ($Kelvin$) }
2516    
2517    \noindent
2518    The diagnostic {\bf TAVE} is simply the time-averaged Temperature over
2519    the {\bf NTAVE} output frequency.  This is contrasted to the instantaneous
2520    Temperature which is archived on the Prognostic Output data stream.
2521    \[
2522    {\bf TAVE} = T(\lambda, \phi, level , t)
2523    \]
2524    \\
2525    
2526    \noindent
2527    { \underline {QAVE} Time-Averaged Specific Humidity ($g/kg$) }
2528    
2529    \noindent
2530    The diagnostic {\bf QAVE} is simply the time-averaged Specific Humidity over
2531    the {\bf NQAVE} output frequency.  This is contrasted to the instantaneous
2532    Specific Humidity which is archived on the Prognostic Output data stream.
2533    \[
2534    {\bf QAVE} = q(\lambda, \phi, level , t)
2535    \]
2536    \\
2537    
2538    \noindent
2539    { \underline {PAVE} Time-Averaged Surface Pressure - PTOP ($mb$) }
2540    
2541    \noindent
2542    The diagnostic {\bf PAVE} is simply the time-averaged Surface Pressure - PTOP over
2543    the {\bf NPAVE} output frequency.  This is contrasted to the instantaneous
2544    Surface Pressure - PTOP which is archived on the Prognostic Output data stream.
2545    \begin{eqnarray*}
2546    {\bf PAVE} & =  & \pi(\lambda, \phi, level , t) \\
2547               & =  & p_s(\lambda, \phi, level , t) - p_T
2548    \end{eqnarray*}
2549    \\
2550    
2551    
2552    \noindent
2553    { \underline {QQAVE} Time-Averaged Turbulent Kinetic Energy $(m/sec)^2$ }
2554    
2555    \noindent
2556    The diagnostic {\bf QQAVE} is simply the time-averaged prognostic Turbulent Kinetic Energy
2557    produced by the GCM Turbulence parameterization over
2558    the {\bf NQQAVE} output frequency.  This is contrasted to the instantaneous
2559    Turbulent Kinetic Energy which is archived on the Prognostic Output data stream.
2560    \[
2561    {\bf QQAVE} = qq(\lambda, \phi, level , t)
2562    \]
2563    \\
2564    Note, {\bf QQAVE} is computed and stored at the ``mass-point'' locations on the staggered C-grid.
2565    \\
2566    
2567    \noindent
2568    { \underline {SWGCLR} Net downward clearsky Shortwave flux at the surface ($Watts/m^2$) }
2569    
2570    \noindent
2571    \begin{eqnarray*}
2572    {\bf SWGCLR} & =  & F(clearsky)_{SW,Nrphys+1}^{Net} \\
2573                 & =  & F(clearsky)_{SW,Nrphys+1}^\downarrow - F(clearsky)_{SW,Nrphys+1}^\uparrow
2574    \end{eqnarray*}
2575    \noindent
2576    \\
2577    where Nrphys+1 indicates the lowest model edge-level, or $p = p_{surf}$.
2578    $F(clearsky){SW}^\downarrow$ is
2579    the downward clearsky Shortwave flux and $F(clearsky)_{SW}^\uparrow$ is
2580    the upward clearsky Shortwave flux.
2581    \\
2582    
2583    \noindent
2584    { \underline {DIABU} Total Diabatic Zonal U-Wind Tendency  ($m/sec/day$) }
2585    
2586    \noindent
2587    {\bf DIABU} is the total time-tendency of the Zonal U-Wind due to Diabatic processes
2588    and the Analysis forcing.
2589    \[
2590    {\bf DIABU} = \pp{u}{t}_{Moist} + \pp{u}{t}_{Turbulence} + \pp{u}{t}_{Analysis}
2591    \]
2592    \\
2593    
2594    \noindent
2595    { \underline {DIABV} Total Diabatic Meridional V-Wind Tendency  ($m/sec/day$) }
2596    
2597    \noindent
2598    {\bf DIABV} is the total time-tendency of the Meridional V-Wind due to Diabatic processes
2599    and the Analysis forcing.
2600    \[
2601    {\bf DIABV} = \pp{v}{t}_{Moist} + \pp{v}{t}_{Turbulence} + \pp{v}{t}_{Analysis}
2602    \]
2603    \\
2604    
2605    \noindent
2606    { \underline {DIABT} Total Diabatic Temperature Tendency  ($deg/day$) }
2607    
2608    \noindent
2609    {\bf DIABT} is the total time-tendency of Temperature due to Diabatic processes
2610    and the Analysis forcing.
2611    \begin{eqnarray*}
2612    {\bf DIABT} & = & \pp{T}{t}_{Moist Processes} + \pp{T}{t}_{Shortwave Radiation} \\
2613               & + & \pp{T}{t}_{Longwave Radiation} + \pp{T}{t}_{Turbulence} + \pp{T}{t}_{Analysis}
2614    \end{eqnarray*}
2615    \\
2616    If we define the time-tendency of Temperature due to Diabatic processes as
2617    \begin{eqnarray*}
2618    \pp{T}{t}_{Diabatic} & = & \pp{T}{t}_{Moist Processes} + \pp{T}{t}_{Shortwave Radiation} \\
2619                         & + & \pp{T}{t}_{Longwave Radiation} + \pp{T}{t}_{Turbulence}
2620    \end{eqnarray*}
2621    then, since there are no surface pressure changes due to Diabatic processes, we may write
2622    \[
2623    \pp{T}{t}_{Diabatic} = {p^\kappa \over \pi }\pp{\pi \theta}{t}_{Diabatic}
2624    \]
2625    where $\theta = T/p^\kappa$.  Thus, {\bf DIABT} may be written as
2626    \[
2627    {\bf DIABT} = {p^\kappa \over \pi } \left( \pp{\pi \theta}{t}_{Diabatic} + \pp{\pi \theta}{t}_{Analysis} \right)
2628    \]
2629    \\
2630    
2631    \noindent
2632    { \underline {DIABQ} Total Diabatic Specific Humidity Tendency  ($g/kg/day$) }
2633    
2634    \noindent
2635    {\bf DIABQ} is the total time-tendency of Specific Humidity due to Diabatic processes
2636    and the Analysis forcing.
2637    \[
2638    {\bf DIABQ} = \pp{q}{t}_{Moist Processes} + \pp{q}{t}_{Turbulence} + \pp{q}{t}_{Analysis}
2639    \]
2640    If we define the time-tendency of Specific Humidity due to Diabatic processes as
2641    \[
2642    \pp{q}{t}_{Diabatic} = \pp{q}{t}_{Moist Processes} + \pp{q}{t}_{Turbulence}
2643    \]
2644    then, since there are no surface pressure changes due to Diabatic processes, we may write
2645    \[
2646    \pp{q}{t}_{Diabatic} = {1 \over \pi }\pp{\pi q}{t}_{Diabatic}
2647    \]
2648    Thus, {\bf DIABQ} may be written as
2649    \[
2650    {\bf DIABQ} = {1 \over \pi } \left( \pp{\pi q}{t}_{Diabatic} + \pp{\pi q}{t}_{Analysis} \right)
2651    \]
2652    \\
2653    
2654    \noindent
2655    { \underline {VINTUQ} Vertically Integrated Moisture Flux ($m/sec \cdot g/kg$) }
2656    
2657    \noindent
2658    The vertically integrated moisture flux due to the zonal u-wind is obtained by integrating
2659    $u q$ over the depth of the atmosphere at each model timestep,
2660    and dividing by the total mass of the column.
2661    \[
2662    {\bf VINTUQ} = \frac{ \int_{surf}^{top} u q \rho dz  } { \int_{surf}^{top} \rho dz  }
2663    \]
2664    Using $\rho \delta z = -{\delta p \over g} = - {1 \over g} \delta p$, we have
2665    \[
2666    {\bf VINTUQ} = { \int_0^1 u q dp  }
2667    \]
2668    \\
2669    
2670    
2671    \noindent
2672    { \underline {VINTVQ} Vertically Integrated Moisture Flux ($m/sec \cdot g/kg$) }
2673    
2674    \noindent
2675    The vertically integrated moisture flux due to the meridional v-wind is obtained by integrating
2676    $v q$ over the depth of the atmosphere at each model timestep,
2677    and dividing by the total mass of the column.
2678    \[
2679    {\bf VINTVQ} = \frac{ \int_{surf}^{top} v q \rho dz  } { \int_{surf}^{top} \rho dz  }
2680    \]
2681    Using $\rho \delta z = -{\delta p \over g} = - {1 \over g} \delta p$, we have
2682    \[
2683    {\bf VINTVQ} = { \int_0^1 v q dp  }
2684    \]
2685    \\
2686    
2687    
2688    \noindent
2689    { \underline {VINTUT} Vertically Integrated Heat Flux ($m/sec \cdot deg$) }
2690    
2691    \noindent
2692    The vertically integrated heat flux due to the zonal u-wind is obtained by integrating
2693    $u T$ over the depth of the atmosphere at each model timestep,
2694    and dividing by the total mass of the column.
2695    \[
2696    {\bf VINTUT} = \frac{ \int_{surf}^{top} u T \rho dz  } { \int_{surf}^{top} \rho dz  }
2697    \]
2698    Or,
2699    \[
2700    {\bf VINTUT} = { \int_0^1 u T dp  }
2701    \]
2702    \\
2703    
2704    \noindent
2705    { \underline {VINTVT} Vertically Integrated Heat Flux ($m/sec \cdot deg$) }
2706    
2707    \noindent
2708    The vertically integrated heat flux due to the meridional v-wind is obtained by integrating
2709    $v T$ over the depth of the atmosphere at each model timestep,
2710    and dividing by the total mass of the column.
2711    \[
2712    {\bf VINTVT} = \frac{ \int_{surf}^{top} v T \rho dz  } { \int_{surf}^{top} \rho dz  }
2713    \]
2714    Using $\rho \delta z = -{\delta p \over g} $, we have
2715    \[
2716    {\bf VINTVT} = { \int_0^1 v T dp  }
2717    \]
2718    \\
2719    
2720    \noindent
2721    { \underline {CLDFRC} Total 2-Dimensional Cloud Fracton ($0-1$) }
2722    
2723    If we define the
2724    time-averaged random and maximum overlapped cloudiness as CLRO and
2725    CLMO respectively, then the probability of clear sky associated
2726    with random overlapped clouds at any level is (1-CLRO) while the probability of
2727    clear sky associated with maximum overlapped clouds at any level is (1-CLMO).
2728    The total clear sky probability is given by (1-CLRO)*(1-CLMO), thus
2729    the total cloud fraction at each  level may be obtained by
2730    1-(1-CLRO)*(1-CLMO).
2731    
2732    At any given level, we may define the clear line-of-site probability by
2733    appropriately accounting for the maximum and random overlap
2734    cloudiness.  The clear line-of-site probability is defined to be
2735    equal to the product of the clear line-of-site probabilities
2736    associated with random and maximum overlap cloudiness.  The clear
2737    line-of-site probability $C(p,p^{\prime})$ associated with maximum overlap clouds,
2738    from the current pressure $p$
2739    to the model top pressure, $p^{\prime} = p_{top}$, or the model surface pressure, $p^{\prime} = p_{surf}$,
2740    is simply 1.0 minus the largest maximum overlap cloud value along  the
2741    line-of-site, ie.
2742    
2743    $$1-MAX_p^{p^{\prime}} \left( CLMO_p \right)$$
2744    
2745    Thus, even in the time-averaged sense it is assumed that the
2746    maximum overlap clouds are correlated in the vertical.  The clear
2747    line-of-site probability associated with random overlap clouds is
2748    defined to be the product of the clear sky probabilities at each
2749    level along the line-of-site, ie.
2750    
2751    $$\prod_{p}^{p^{\prime}} \left( 1-CLRO_p \right)$$
2752    
2753    The total cloud fraction at a given level associated with a line-
2754    of-site calculation is given by
2755    
2756    $$1-\left( 1-MAX_p^{p^{\prime}} \left[ CLMO_p \right] \right)
2757        \prod_p^{p^{\prime}} \left( 1-CLRO_p \right)$$
2758    
2759    
2760    \noindent
2761    The 2-dimensional net cloud fraction as seen from the top of the
2762    atmosphere is given by
2763    \[
2764    {\bf CLDFRC} = 1-\left( 1-MAX_{l=l_1}^{Nrphys} \left[ CLMO_l \right] \right)
2765        \prod_{l=l_1}^{Nrphys} \left( 1-CLRO_l \right)
2766    \]
2767    \\
2768    For a complete description of cloud/radiative interactions, see Section \ref{sec:fizhi:radcloud}.
2769    
2770    
2771    \noindent
2772    { \underline {QINT} Total Precipitable Water ($gm/cm^2$) }
2773    
2774    \noindent
2775    The Total Precipitable Water is defined as the vertical integral of the specific humidity,
2776    given by:
2777    \begin{eqnarray*}
2778    {\bf QINT} & = & \int_{surf}^{top} \rho q dz \\
2779               & = & {\pi \over g} \int_0^1 q dp
2780    \end{eqnarray*}
2781    where we have used the hydrostatic relation
2782    $\rho \delta z = -{\delta p \over g} $.
2783    \\
2784    
2785    
2786    \noindent
2787    { \underline {U2M}  Zonal U-Wind at 2 Meter Depth ($m/sec$) }
2788    
2789    \noindent
2790    The u-wind at the 2-meter depth is determined from the similarity theory:
2791    \[
2792    {\bf U2M} = {u_* \over k} \psi_{m_{2m}} {u_{sl} \over {W_s}} =
2793    { \psi_{m_{2m}} \over {\psi_{m_{sl}} }}u_{sl}
2794    \]
2795    
2796    \noindent
2797    where $\psi_m(2m)$ is the non-dimensional wind shear at two meters, and the subscript
2798    $sl$ refers to the height of the top of the surface layer. If the roughness height
2799    is above two meters, ${\bf U2M}$ is undefined.
2800    \\
2801    
2802    \noindent
2803    { \underline {V2M}  Meridional V-Wind at 2 Meter Depth ($m/sec$) }
2804    
2805    \noindent
2806    The v-wind at the 2-meter depth is a determined from the similarity theory:
2807    \[
2808    {\bf V2M} = {u_* \over k} \psi_{m_{2m}} {v_{sl} \over {W_s}} =
2809    { \psi_{m_{2m}} \over {\psi_{m_{sl}} }}v_{sl}
2810    \]
2811    
2812    \noindent
2813    where $\psi_m(2m)$ is the non-dimensional wind shear at two meters, and the subscript
2814    $sl$ refers to the height of the top of the surface layer. If the roughness height
2815    is above two meters, ${\bf V2M}$ is undefined.
2816    \\
2817    
2818    \noindent
2819    { \underline {T2M}  Temperature at 2 Meter Depth ($deg \hspace{.1cm} K$) }
2820    
2821    \noindent
2822    The temperature at the 2-meter depth is a determined from the similarity theory:
2823    \[
2824    {\bf T2M} = P^{\kappa} ({\theta* \over k} ({\psi_{h_{2m}}+\psi_g}) + \theta_{surf} ) =
2825    P^{\kappa}(\theta_{surf} + { {\psi_{h_{2m}}+\psi_g} \over {{\psi_{h_{sl}}+\psi_g}} }
2826    (\theta_{sl} - \theta_{surf}))
2827    \]
2828    where:
2829    \[
2830    \theta_* = - { (\overline{w^{\prime}\theta^{\prime}}) \over {u_*} }
2831    \]
2832    
2833    \noindent
2834    where $\psi_h(2m)$ is the non-dimensional temperature gradient at two meters, $\psi_g$ is
2835    the non-dimensional temperature gradient in the viscous sublayer, and the subscript
2836    $sl$ refers to the height of the top of the surface layer. If the roughness height
2837    is above two meters, ${\bf T2M}$ is undefined.
2838    \\
2839    
2840    \noindent
2841    { \underline {Q2M}  Specific Humidity at 2 Meter Depth ($g/kg$) }
2842    
2843    \noindent
2844    The specific humidity at the 2-meter depth is determined from the similarity theory:
2845    \[
2846    {\bf Q2M} = P^{\kappa} ({q_* \over k} ({\psi_{h_{2m}}+\psi_g}) + q_{surf} ) =
2847    P^{\kappa}(q_{surf} + { {\psi_{h_{2m}}+\psi_g} \over {{\psi_{h_{sl}}+\psi_g}} }
2848    (q_{sl} - q_{surf}))
2849    \]
2850    where:
2851    \[
2852    q_* = - { (\overline{w^{\prime}q^{\prime}}) \over {u_*} }
2853    \]
2854    
2855    \noindent
2856    where $\psi_h(2m)$ is the non-dimensional temperature gradient at two meters, $\psi_g$ is
2857    the non-dimensional temperature gradient in the viscous sublayer, and the subscript
2858    $sl$ refers to the height of the top of the surface layer. If the roughness height
2859    is above two meters, ${\bf Q2M}$ is undefined.
2860    \\
2861    
2862    \noindent
2863    { \underline {U10M}  Zonal U-Wind at 10 Meter Depth ($m/sec$) }
2864    
2865    \noindent
2866    The u-wind at the 10-meter depth is an interpolation between the surface wind
2867    and the model lowest level wind using the ratio of the non-dimensional wind shear
2868    at the two levels:
2869    \[
2870    {\bf U10M} = {u_* \over k} \psi_{m_{10m}} {u_{sl} \over {W_s}} =
2871    { \psi_{m_{10m}} \over {\psi_{m_{sl}} }}u_{sl}
2872    \]
2873    
2874    \noindent
2875    where $\psi_m(10m)$ is the non-dimensional wind shear at ten meters, and the subscript
2876    $sl$ refers to the height of the top of the surface layer.
2877    \\
2878    
2879    \noindent
2880    { \underline {V10M}  Meridional V-Wind at 10 Meter Depth ($m/sec$) }
2881    
2882    \noindent
2883    The v-wind at the 10-meter depth is an interpolation between the surface wind
2884    and the model lowest level wind using the ratio of the non-dimensional wind shear
2885    at the two levels:
2886    \[
2887    {\bf V10M} = {u_* \over k} \psi_{m_{10m}} {v_{sl} \over {W_s}} =
2888    { \psi_{m_{10m}} \over {\psi_{m_{sl}} }}v_{sl}
2889    \]
2890    
2891    \noindent
2892    where $\psi_m(10m)$ is the non-dimensional wind shear at ten meters, and the subscript
2893    $sl$ refers to the height of the top of the surface layer.
2894    \\
2895    
2896    \noindent
2897    { \underline {T10M}  Temperature at 10 Meter Depth ($deg \hspace{.1cm} K$) }
2898    
2899    \noindent
2900    The temperature at the 10-meter depth is an interpolation between the surface potential
2901    temperature and the model lowest level potential temperature using the ratio of the
2902    non-dimensional temperature gradient at the two levels:
2903    \[
2904    {\bf T10M} = P^{\kappa} ({\theta* \over k} ({\psi_{h_{10m}}+\psi_g}) + \theta_{surf} ) =
2905    P^{\kappa}(\theta_{surf} + { {\psi_{h_{10m}}+\psi_g} \over {{\psi_{h_{sl}}+\psi_g}} }
2906    (\theta_{sl} - \theta_{surf}))
2907    \]
2908    where:
2909    \[
2910    \theta_* = - { (\overline{w^{\prime}\theta^{\prime}}) \over {u_*} }
2911    \]
2912    
2913    \noindent
2914    where $\psi_h(10m)$ is the non-dimensional temperature gradient at two meters, $\psi_g$ is
2915    the non-dimensional temperature gradient in the viscous sublayer, and the subscript
2916    $sl$ refers to the height of the top of the surface layer.
2917    \\
2918    
2919    \noindent
2920    { \underline {Q10M}  Specific Humidity at 10 Meter Depth ($g/kg$) }
2921    
2922    \noindent
2923    The specific humidity at the 10-meter depth is an interpolation between the surface specific
2924    humidity and the model lowest level specific humidity using the ratio of the
2925    non-dimensional temperature gradient at the two levels:
2926    \[
2927    {\bf Q10M} = P^{\kappa} ({q_* \over k} ({\psi_{h_{10m}}+\psi_g}) + q_{surf} ) =
2928    P^{\kappa}(q_{surf} + { {\psi_{h_{10m}}+\psi_g} \over {{\psi_{h_{sl}}+\psi_g}} }
2929    (q_{sl} - q_{surf}))
2930    \]
2931    where:
2932    \[
2933    q_* =  - { (\overline{w^{\prime}q^{\prime}}) \over {u_*} }
2934    \]
2935    
2936    \noindent
2937    where $\psi_h(10m)$ is the non-dimensional temperature gradient at two meters, $\psi_g$ is
2938    the non-dimensional temperature gradient in the viscous sublayer, and the subscript
2939    $sl$ refers to the height of the top of the surface layer.
2940    \\
2941    
2942    \noindent
2943    { \underline {DTRAIN} Cloud Detrainment Mass Flux ($kg/m^2$) }
2944    
2945    The amount of cloud mass moved per RAS timestep at the cloud detrainment level is written:
2946    \[
2947    {\bf DTRAIN} = \eta_{r_D}m_B
2948    \]
2949    \noindent
2950    where $r_D$ is the detrainment level,
2951    $m_B$ is the cloud base mass flux, and $\eta$
2952    is the entrainment, defined in Section \ref{sec:fizhi:mc}.
2953    \\
2954    
2955    \noindent
2956    { \underline {QFILL}  Filling of negative Specific Humidity ($g/kg/day$) }
2957    
2958    \noindent
2959    Due to computational errors associated with the numerical scheme used for
2960    the advection of moisture, negative values of specific humidity may be generated.  The
2961    specific humidity is checked for negative values after every dynamics timestep.  If negative
2962    values have been produced, a filling algorithm is invoked which redistributes moisture from
2963    below.  Diagnostic {\bf QFILL} is equal to the net filling needed
2964    to eliminate negative specific humidity, scaled to a per-day rate:
2965    \[
2966    {\bf QFILL} = q^{n+1}_{final} - q^{n+1}_{initial}
2967    \]
2968    where
2969    \[
2970    q^{n+1} = (\pi q)^{n+1} / \pi^{n+1}
2971    \]
2972    
2973    
2974    \subsubsection{Key subroutines, parameters and files}
2975    
2976    \subsubsection{Dos and donts}
2977    
2978    \subsubsection{Fizhi Reference}

Legend:
Removed from v.1.3  
changed lines
  Added in v.1.13

  ViewVC Help
Powered by ViewVC 1.1.22