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revision 1.2 by molod, Wed Jan 28 18:21:33 2004 UTC revision 1.18 by jmc, Fri Aug 27 13:15:37 2010 UTC
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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}
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 38  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 96  $\alpha$ 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 119  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 161  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{s_phys_pkgs/figs/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 181  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 216  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 300  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 352  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 382  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 423  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 453  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 487  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  \[  \[
492  K_h  K_h
# Line 563  where $\psi_h$ is the surface layer non- Line 561  where $\psi_h$ is the surface layer non-
561  \]  \]
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  \[  \[
571  \psi_{g} = { 0.55 (Pr^{2/3} - 0.2) \over \nu^{1/2} }  \psi_{g} = { 0.55 (Pr^{2/3} - 0.2) \over \nu^{1/2} }
572  (h_{0}u_{*} - h_{0_{ref}}u_{*_{ref}})^{1/2}  (h_{0}u_{*} - h_{0_{ref}}u_{*_{ref}})^{1/2}
# Line 582  The surface roughness length over oceans Line 580  The surface roughness length over oceans
580  {z_0} = c_1u^3_* + c_2u^2_* + c_3u_* + c_4 + {c_5 \over {u_*}}  {z_0} = c_1u^3_* + c_2u^2_* + c_3u_* + c_4 + {c_5 \over {u_*}}
581  \]  \]
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 597  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 612  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 655  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 667  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 707  Type & Vegetation Designation \\ \hline Line 705  Type & Vegetation Designation \\ \hline
705  100 & Ocean \\ \hline  100 & Ocean \\ \hline
706  \end{tabular}  \end{tabular}
707  \end{center}  \end{center}
708  \caption{Surface type designations used to compute surface roughness (over land)  \caption{Surface type designations.}
 and surface albedo.}  
709  \label{tab:fizhi:surftype}  \label{tab:fizhi:surftype}
710  \end{table}  \end{table}
711    
   
712  \begin{figure*}[htbp]  \begin{figure*}[htbp]
713    \centerline{  \epsfysize=7in  \epsfbox{surftypes.ps}}    \centerline{  \epsfysize=4.0in  \epsfbox{s_phys_pkgs/figs/surftype.eps}}
714    \vspace{0.3in}    \vspace{0.2in}
715    \caption  {Surface Type Compinations at \txt resolution.}    \caption  {Surface Type Combinations.}
716    \label{fig:fizhi:surftype}    \label{fig:fizhi:surftype}
717  \end{figure*}  \end{figure*}
718    
719  \begin{figure*}[htbp]  % \rotatebox{270}{\centerline{  \epsfysize=4in  \epsfbox{s_phys_pkgs/figs/surftypes.eps}}}
720    \centerline{  \epsfysize=7in  \epsfbox{surftypes.descrip.ps}}  % \rotatebox{270}{\centerline{  \epsfysize=4in  \epsfbox{s_phys_pkgs/figs/surftypes.descrip.eps}}}
721    \vspace{0.3in}  %\begin{figure*}[htbp]
722    \caption  {Surface Type Descriptions.}  %  \centerline{  \epsfysize=4in  \epsfbox{s_phys_pkgs/figs/surftypes.descrip.ps}}
723    \label{fig:fizhi:surftype.desc}  %  \vspace{0.3in}
724  \end{figure*}  %  \caption  {Surface Type Descriptions.}
725    %  \label{fig:fizhi:surftype.desc}
726    %\end{figure*}
727    
728    
729  \subsubsection{Surface Roughness}  \paragraph{Surface Roughness}
730  The surface roughness length over oceans is computed iteratively with the wind  The surface roughness length over oceans is computed iteratively with the wind
731  stress by the surface layer parameterization (Helfand and Schubert, 1991).  stress by the surface layer parameterization (\cite{helfschu:95}).
732  It employs an interpolation between the functions of Large and Pond (1981)  It employs an interpolation between the functions of \cite{larpond:81}
733  for high winds and of Kondo (1975) for weak winds.  for high winds and of \cite{kondo:75} for weak winds.
734    
735    
736  \subsubsection{Albedo}  \paragraph{Albedo}
737  The surface albedo computation, described in Koster and Suarez (1991),  The surface albedo computation, described in \cite{ks:91},
738  employs the ``two stream'' approximation used in Sellers' (1987) Simple Biosphere (SiB)  employs the ``two stream'' approximation used in Sellers' (1987) Simple Biosphere (SiB)
739  Model which distinguishes between the direct and diffuse albedos in the visible  Model which distinguishes between the direct and diffuse albedos in the visible
740  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 745  sun), the greenness fraction, the vegeta Line 743  sun), the greenness fraction, the vegeta
743  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
744  to the height of the vegetation elements.  to the height of the vegetation elements.
745    
746  \subsubsection{Gravity Wave Drag}  \paragraph{Gravity Wave Drag}
747  The fizhi package employs the gravity wave drag scheme of Zhou et al. (1996).  
748    The fizhi package employs the gravity wave drag scheme of \cite{zhouetal:95}).
749  This scheme is a modified version of Vernekar et al. (1992),  This scheme is a modified version of Vernekar et al. (1992),
750  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).  
751  In this version, the gravity wave stress at the surface is  In this version, the gravity wave stress at the surface is
# Line 763  A modification introduced by Zhou et al. Line 762  A modification introduced by Zhou et al.
762  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.  
763  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.
764    
765  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}.
766  Experiments using the gravity wave drag parameterization yielded significant and  Experiments using the gravity wave drag parameterization yielded significant and
767  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
768  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 779  of mountain torque (through a redistribu Line 778  of mountain torque (through a redistribu
778  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).  
779    
780    
781  \subsubsection{Boundary Conditions and other Input Data}  Boundary Conditions and other Input Data:
782    
783  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
784  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 787  fields include:  sea surface temperature Line 786  fields include:  sea surface temperature
786  vegetation index, and the radiation-related background levels of: ozone, carbon dioxide,  vegetation index, and the radiation-related background levels of: ozone, carbon dioxide,
787  and stratospheric moisture.  and stratospheric moisture.
788    
789  Boundary condition data sets are available at the model's \fxf and \txt  Boundary condition data sets are available at the model's
790  resolutions for either climatological or yearly varying conditions.  resolutions for either climatological or yearly varying conditions.
791  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;
792  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}\@.
793  The time mean values are interpolated during each model timestep to the  The time mean values are interpolated during each model timestep to the
794  current time. Future model versions will incorporate boundary conditions at  current time.
 higher spatial \mbox{($1^\circ$ x $1^\circ$)} resolutions.  
795    
796  \begin{table}[htb]  \begin{table}[htb]
797  \begin{center}  \begin{center}
# Line 815  current years and frequencies available. Line 813  current years and frequencies available.
813  \end{table}  \end{table}
814    
815    
816  \subsubsection{Topography and Topography Variance}  \paragraph{Topography and Topography Variance}
817    
818  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
819  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
820  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
821  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.  
   
 \begin{figure*}[htbp]  
   \centerline{  \epsfysize=7.0in  \epsfbox{lanczos.ps}}  
   \caption{ \label{fig:fizhi:lanczos} Comparison between the Lanczos and $mth$-order Shapiro filter  
   response functions for $m$ = 2, 4, and 8. }  
 \end{figure*}  
822    
823  The standard deviation of the subgrid-scale topography  The standard deviation of the subgrid-scale topography is computed by interpolating the 10 minute
824  is computed from a modified version of the the Navy 10 minute by 10 minute dataset.  data to the model's resolution and re-interpolating back to the 10 minute by 10 minute resolution.
 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.  
825  The sub-grid scale variance is constructed based on this smoothed dataset.  The sub-grid scale variance is constructed based on this smoothed dataset.
826    
827    
828  \subsubsection{Upper Level Moisture}  \paragraph{Upper Level Moisture}
829  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
830  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
831  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
832  model's grid location and current time, and blended with the GCM's moisture data.  Below 300 mb,  model's grid location and current time, and blended with the GCM's moisture data.  Below 300 mb,
833  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,
834  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.
835    
836    
837    \subsubsection{Fizhi Diagnostics}
838    
839    Fizhi Diagnostic Menu:
840    \label{sec:pkg:fizhi:diagnostics}
841    
842    \begin{tabular}{llll}
843    \hline\hline
844     NAME & UNITS & LEVELS & DESCRIPTION \\
845    \hline
846    
847    &\\
848     UFLUX    &   $Newton/m^2$  &    1  
849             &\begin{minipage}[t]{3in}
850              {Surface U-Wind Stress on the atmosphere}
851             \end{minipage}\\
852     VFLUX    &   $Newton/m^2$  &    1  
853             &\begin{minipage}[t]{3in}
854              {Surface V-Wind Stress on the atmosphere}
855             \end{minipage}\\
856     HFLUX    &   $Watts/m^2$  &    1  
857             &\begin{minipage}[t]{3in}
858              {Surface Flux of Sensible Heat}
859             \end{minipage}\\
860     EFLUX    &   $Watts/m^2$  &    1  
861             &\begin{minipage}[t]{3in}
862              {Surface Flux of Latent Heat}
863             \end{minipage}\\
864     QICE     &   $Watts/m^2$  &    1  
865             &\begin{minipage}[t]{3in}
866              {Heat Conduction through Sea-Ice}
867             \end{minipage}\\
868     RADLWG   &   $Watts/m^2$ &    1  
869             &\begin{minipage}[t]{3in}
870              {Net upward LW flux at the ground}
871             \end{minipage}\\
872     RADSWG   &   $Watts/m^2$  &    1
873             &\begin{minipage}[t]{3in}
874              {Net downward SW flux at the ground}
875             \end{minipage}\\
876     RI       &  $dimensionless$ &  Nrphys
877             &\begin{minipage}[t]{3in}
878              {Richardson Number}
879             \end{minipage}\\
880     CT       &  $dimensionless$ &  1
881             &\begin{minipage}[t]{3in}
882              {Surface Drag coefficient for T and Q}
883             \end{minipage}\\
884     CU       & $dimensionless$ &  1
885         &\begin{minipage}[t]{3in}
886          {Surface Drag coefficient for U and V}
887         \end{minipage}\\
888     ET       &  $m^2/sec$ &  Nrphys
889         &\begin{minipage}[t]{3in}
890          {Diffusivity coefficient for T and Q}
891         \end{minipage}\\
892     EU       &  $m^2/sec$ &  Nrphys
893         &\begin{minipage}[t]{3in}
894          {Diffusivity coefficient for U and V}
895         \end{minipage}\\
896     TURBU    &  $m/sec/day$ &  Nrphys
897         &\begin{minipage}[t]{3in}
898          {U-Momentum Changes due to Turbulence}
899         \end{minipage}\\
900     TURBV    &  $m/sec/day$ &  Nrphys
901         &\begin{minipage}[t]{3in}
902          {V-Momentum Changes due to Turbulence}
903         \end{minipage}\\
904     TURBT    &  $deg/day$ &  Nrphys
905         &\begin{minipage}[t]{3in}
906          {Temperature Changes due to Turbulence}
907         \end{minipage}\\
908     TURBQ    &  $g/kg/day$ &  Nrphys
909         &\begin{minipage}[t]{3in}
910          {Specific Humidity Changes due to Turbulence}
911         \end{minipage}\\
912     MOISTT   &   $deg/day$ &  Nrphys
913         &\begin{minipage}[t]{3in}
914          {Temperature Changes due to Moist Processes}
915         \end{minipage}\\
916     MOISTQ   &  $g/kg/day$ &  Nrphys
917         &\begin{minipage}[t]{3in}
918          {Specific Humidity Changes due to Moist Processes}
919         \end{minipage}\\
920     RADLW    &  $deg/day$ &  Nrphys
921         &\begin{minipage}[t]{3in}
922          {Net Longwave heating rate for each level}
923         \end{minipage}\\
924     RADSW    &  $deg/day$ &  Nrphys
925         &\begin{minipage}[t]{3in}
926          {Net Shortwave heating rate for each level}
927         \end{minipage}\\
928     PREACC   &  $mm/day$ &  1
929         &\begin{minipage}[t]{3in}
930          {Total Precipitation}
931         \end{minipage}\\
932     PRECON   &  $mm/day$ &  1
933         &\begin{minipage}[t]{3in}
934          {Convective Precipitation}
935         \end{minipage}\\
936     TUFLUX   &  $Newton/m^2$ &  Nrphys
937         &\begin{minipage}[t]{3in}
938          {Turbulent Flux of U-Momentum}
939         \end{minipage}\\
940     TVFLUX   &  $Newton/m^2$ &  Nrphys
941         &\begin{minipage}[t]{3in}
942          {Turbulent Flux of V-Momentum}
943         \end{minipage}\\
944     TTFLUX   &  $Watts/m^2$ &  Nrphys
945         &\begin{minipage}[t]{3in}
946          {Turbulent Flux of Sensible Heat}
947         \end{minipage}\\
948    \end{tabular}
949    
950    \newpage
951    \vspace*{\fill}
952    \begin{tabular}{llll}
953    \hline\hline
954     NAME & UNITS & LEVELS & DESCRIPTION \\
955    \hline
956    
957    &\\
958     TQFLUX   &  $Watts/m^2$ &  Nrphys
959         &\begin{minipage}[t]{3in}
960          {Turbulent Flux of Latent Heat}
961         \end{minipage}\\
962     CN       &  $dimensionless$ &  1
963         &\begin{minipage}[t]{3in}
964          {Neutral Drag Coefficient}
965         \end{minipage}\\
966     WINDS     &  $m/sec$ &  1
967         &\begin{minipage}[t]{3in}
968          {Surface Wind Speed}
969         \end{minipage}\\
970     DTSRF     &  $deg$ &  1
971         &\begin{minipage}[t]{3in}
972          {Air/Surface virtual temperature difference}
973         \end{minipage}\\
974     TG        &  $deg$ &  1
975         &\begin{minipage}[t]{3in}
976          {Ground temperature}
977         \end{minipage}\\
978     TS        &  $deg$ &  1
979         &\begin{minipage}[t]{3in}
980          {Surface air temperature (Adiabatic from lowest model layer)}
981         \end{minipage}\\
982     DTG       &  $deg$ &  1
983         &\begin{minipage}[t]{3in}
984          {Ground temperature adjustment}
985         \end{minipage}\\
986    
987     QG        &  $g/kg$ &  1
988         &\begin{minipage}[t]{3in}
989          {Ground specific humidity}
990         \end{minipage}\\
991     QS        &  $g/kg$ &  1
992         &\begin{minipage}[t]{3in}
993          {Saturation surface specific humidity}
994         \end{minipage}\\
995     TGRLW    &    $deg$   &    1  
996         &\begin{minipage}[t]{3in}
997          {Instantaneous ground temperature used as input to the
998           Longwave radiation subroutine}
999         \end{minipage}\\
1000     ST4      &   $Watts/m^2$  &    1  
1001         &\begin{minipage}[t]{3in}
1002          {Upward Longwave flux at the ground ($\sigma T^4$)}
1003         \end{minipage}\\
1004     OLR      &   $Watts/m^2$  &    1  
1005         &\begin{minipage}[t]{3in}
1006          {Net upward Longwave flux at the top of the model}
1007         \end{minipage}\\
1008     OLRCLR   &   $Watts/m^2$  &    1  
1009         &\begin{minipage}[t]{3in}
1010          {Net upward clearsky Longwave flux at the top of the model}
1011         \end{minipage}\\
1012     LWGCLR   &   $Watts/m^2$  &    1  
1013         &\begin{minipage}[t]{3in}
1014          {Net upward clearsky Longwave flux at the ground}
1015         \end{minipage}\\
1016     LWCLR    &  $deg/day$ &  Nrphys
1017         &\begin{minipage}[t]{3in}
1018          {Net clearsky Longwave heating rate for each level}
1019         \end{minipage}\\
1020     TLW      &    $deg$   &  Nrphys
1021         &\begin{minipage}[t]{3in}
1022          {Instantaneous temperature used as input to the Longwave radiation
1023          subroutine}
1024         \end{minipage}\\
1025     SHLW     &    $g/g$   &  Nrphys
1026         &\begin{minipage}[t]{3in}
1027          {Instantaneous specific humidity used as input to the Longwave radiation
1028          subroutine}
1029         \end{minipage}\\
1030     OZLW     &    $g/g$   &  Nrphys
1031         &\begin{minipage}[t]{3in}
1032          {Instantaneous ozone used as input to the Longwave radiation
1033          subroutine}
1034         \end{minipage}\\
1035     CLMOLW   &    $0-1$   &  Nrphys
1036         &\begin{minipage}[t]{3in}
1037          {Maximum overlap cloud fraction used in the Longwave radiation
1038          subroutine}
1039         \end{minipage}\\
1040     CLDTOT   &    $0-1$   &  Nrphys
1041         &\begin{minipage}[t]{3in}
1042          {Total cloud fraction used in the Longwave and Shortwave radiation
1043          subroutines}
1044         \end{minipage}\\
1045     LWGDOWN  &    $Watts/m^2$   &  1
1046         &\begin{minipage}[t]{3in}
1047          {Downwelling Longwave radiation at the ground}
1048         \end{minipage}\\
1049     GWDT     &    $deg/day$ &  Nrphys
1050         &\begin{minipage}[t]{3in}
1051          {Temperature tendency due to Gravity Wave Drag}
1052         \end{minipage}\\
1053     RADSWT   &    $Watts/m^2$   &  1
1054         &\begin{minipage}[t]{3in}
1055          {Incident Shortwave radiation at the top of the atmosphere}
1056         \end{minipage}\\
1057     TAUCLD   &    $per 100 mb$   &  Nrphys
1058         &\begin{minipage}[t]{3in}
1059          {Counted Cloud Optical Depth (non-dimensional) per 100 mb}
1060         \end{minipage}\\
1061     TAUCLDC  &    $Number$   &  Nrphys
1062         &\begin{minipage}[t]{3in}
1063          {Cloud Optical Depth Counter}
1064         \end{minipage}\\
1065    \end{tabular}
1066    \vfill
1067    
1068    \newpage
1069    \vspace*{\fill}
1070    \begin{tabular}{llll}
1071    \hline\hline
1072     NAME & UNITS & LEVELS & DESCRIPTION \\
1073    \hline
1074    
1075    &\\
1076     CLDLOW   &    $0-1$   &  Nrphys
1077         &\begin{minipage}[t]{3in}
1078          {Low-Level ( 1000-700 hPa) Cloud Fraction  (0-1)}
1079         \end{minipage}\\
1080     EVAP     &    $mm/day$   &  1
1081         &\begin{minipage}[t]{3in}
1082          {Surface evaporation}
1083         \end{minipage}\\
1084     DPDT     &    $hPa/day$ &  1
1085         &\begin{minipage}[t]{3in}
1086          {Surface Pressure tendency}
1087         \end{minipage}\\
1088     UAVE     &    $m/sec$ &  Nrphys
1089         &\begin{minipage}[t]{3in}
1090          {Average U-Wind}
1091         \end{minipage}\\
1092     VAVE     &    $m/sec$ &  Nrphys
1093         &\begin{minipage}[t]{3in}
1094          {Average V-Wind}
1095         \end{minipage}\\
1096     TAVE     &    $deg$ &  Nrphys
1097         &\begin{minipage}[t]{3in}
1098          {Average Temperature}
1099         \end{minipage}\\
1100     QAVE     &    $g/kg$ &  Nrphys
1101         &\begin{minipage}[t]{3in}
1102          {Average Specific Humidity}
1103         \end{minipage}\\
1104     OMEGA    &    $hPa/day$ &  Nrphys
1105         &\begin{minipage}[t]{3in}
1106          {Vertical Velocity}
1107         \end{minipage}\\
1108     DUDT     &    $m/sec/day$ &  Nrphys
1109         &\begin{minipage}[t]{3in}
1110          {Total U-Wind tendency}
1111         \end{minipage}\\
1112     DVDT     &    $m/sec/day$ &  Nrphys
1113         &\begin{minipage}[t]{3in}
1114          {Total V-Wind tendency}
1115         \end{minipage}\\
1116     DTDT     &    $deg/day$ &  Nrphys
1117         &\begin{minipage}[t]{3in}
1118          {Total Temperature tendency}
1119         \end{minipage}\\
1120     DQDT     &    $g/kg/day$ &  Nrphys
1121         &\begin{minipage}[t]{3in}
1122          {Total Specific Humidity tendency}
1123         \end{minipage}\\
1124     VORT     &    $10^{-4}/sec$ &  Nrphys
1125         &\begin{minipage}[t]{3in}
1126          {Relative Vorticity}
1127         \end{minipage}\\
1128     DTLS     &    $deg/day$ &  Nrphys
1129         &\begin{minipage}[t]{3in}
1130          {Temperature tendency due to Stratiform Cloud Formation}
1131         \end{minipage}\\
1132     DQLS     &    $g/kg/day$ &  Nrphys
1133         &\begin{minipage}[t]{3in}
1134          {Specific Humidity tendency due to Stratiform Cloud Formation}
1135         \end{minipage}\\
1136     USTAR    &    $m/sec$ &  1
1137         &\begin{minipage}[t]{3in}
1138          {Surface USTAR wind}
1139         \end{minipage}\\
1140     Z0       &    $m$ &  1
1141         &\begin{minipage}[t]{3in}
1142          {Surface roughness}
1143         \end{minipage}\\
1144     FRQTRB   &    $0-1$ &  Nrphys-1
1145         &\begin{minipage}[t]{3in}
1146          {Frequency of Turbulence}
1147         \end{minipage}\\
1148     PBL      &    $mb$ &  1
1149         &\begin{minipage}[t]{3in}
1150          {Planetary Boundary Layer depth}
1151         \end{minipage}\\
1152     SWCLR    &  $deg/day$ &  Nrphys
1153         &\begin{minipage}[t]{3in}
1154          {Net clearsky Shortwave heating rate for each level}
1155         \end{minipage}\\
1156     OSR      &   $Watts/m^2$  &    1
1157         &\begin{minipage}[t]{3in}
1158          {Net downward Shortwave flux at the top of the model}
1159         \end{minipage}\\
1160     OSRCLR   &   $Watts/m^2$  &    1  
1161         &\begin{minipage}[t]{3in}
1162          {Net downward clearsky Shortwave flux at the top of the model}
1163         \end{minipage}\\
1164     CLDMAS   &   $kg / m^2$  &    Nrphys
1165         &\begin{minipage}[t]{3in}
1166          {Convective cloud mass flux}
1167         \end{minipage}\\
1168     UAVE     &   $m/sec$  &    Nrphys
1169         &\begin{minipage}[t]{3in}
1170          {Time-averaged $u-Wind$}
1171         \end{minipage}\\
1172    \end{tabular}
1173    \vfill
1174    
1175    \newpage
1176    \vspace*{\fill}
1177    \begin{tabular}{llll}
1178    \hline\hline
1179     NAME & UNITS & LEVELS & DESCRIPTION \\
1180    \hline
1181    
1182    &\\
1183     VAVE     &   $m/sec$  &    Nrphys
1184         &\begin{minipage}[t]{3in}
1185          {Time-averaged $v-Wind$}
1186         \end{minipage}\\
1187     TAVE     &   $deg$  &    Nrphys
1188         &\begin{minipage}[t]{3in}
1189          {Time-averaged $Temperature$}
1190         \end{minipage}\\
1191     QAVE     &   $g/g$  &    Nrphys
1192         &\begin{minipage}[t]{3in}
1193          {Time-averaged $Specific \, \, Humidity$}
1194         \end{minipage}\\
1195     RFT      &    $deg/day$ &  Nrphys
1196         &\begin{minipage}[t]{3in}
1197          {Temperature tendency due Rayleigh Friction}
1198         \end{minipage}\\
1199     PS       &   $mb$  &    1
1200         &\begin{minipage}[t]{3in}
1201          {Surface Pressure}
1202         \end{minipage}\\
1203     QQAVE    &   $(m/sec)^2$  &    Nrphys
1204         &\begin{minipage}[t]{3in}
1205          {Time-averaged $Turbulent Kinetic Energy$}
1206         \end{minipage}\\
1207     SWGCLR   &   $Watts/m^2$  &    1  
1208         &\begin{minipage}[t]{3in}
1209          {Net downward clearsky Shortwave flux at the ground}
1210         \end{minipage}\\
1211     PAVE     &   $mb$  &    1
1212         &\begin{minipage}[t]{3in}
1213          {Time-averaged Surface Pressure}
1214         \end{minipage}\\
1215     DIABU    & $m/sec/day$ &    Nrphys
1216         &\begin{minipage}[t]{3in}
1217          {Total Diabatic forcing on $u-Wind$}
1218         \end{minipage}\\
1219     DIABV    & $m/sec/day$ &    Nrphys
1220         &\begin{minipage}[t]{3in}
1221          {Total Diabatic forcing on $v-Wind$}
1222         \end{minipage}\\
1223     DIABT    & $deg/day$ &    Nrphys
1224         &\begin{minipage}[t]{3in}
1225          {Total Diabatic forcing on $Temperature$}
1226         \end{minipage}\\
1227     DIABQ    & $g/kg/day$ &    Nrphys
1228         &\begin{minipage}[t]{3in}
1229          {Total Diabatic forcing on $Specific \, \, Humidity$}
1230         \end{minipage}\\
1231     RFU      &    $m/sec/day$ &  Nrphys
1232         &\begin{minipage}[t]{3in}
1233          {U-Wind tendency due to Rayleigh Friction}
1234         \end{minipage}\\
1235     RFV      &    $m/sec/day$ &  Nrphys
1236         &\begin{minipage}[t]{3in}
1237          {V-Wind tendency due to Rayleigh Friction}
1238         \end{minipage}\\
1239     GWDU     &    $m/sec/day$ &  Nrphys
1240         &\begin{minipage}[t]{3in}
1241          {U-Wind tendency due to Gravity Wave Drag}
1242         \end{minipage}\\
1243     GWDU     &    $m/sec/day$ &  Nrphys
1244         &\begin{minipage}[t]{3in}
1245          {V-Wind tendency due to Gravity Wave Drag}
1246         \end{minipage}\\
1247     GWDUS    &    $N/m^2$ &  1
1248         &\begin{minipage}[t]{3in}
1249          {U-Wind Gravity Wave Drag Stress at Surface}
1250         \end{minipage}\\
1251     GWDVS    &    $N/m^2$ &  1
1252         &\begin{minipage}[t]{3in}
1253          {V-Wind Gravity Wave Drag Stress at Surface}
1254         \end{minipage}\\
1255     GWDUT    &    $N/m^2$ &  1
1256         &\begin{minipage}[t]{3in}
1257          {U-Wind Gravity Wave Drag Stress at Top}
1258         \end{minipage}\\
1259     GWDVT    &    $N/m^2$ &  1
1260         &\begin{minipage}[t]{3in}
1261          {V-Wind Gravity Wave Drag Stress at Top}
1262         \end{minipage}\\
1263     LZRAD    &    $mg/kg$ &  Nrphys
1264             &\begin{minipage}[t]{3in}
1265              {Estimated Cloud Liquid Water used in Radiation}
1266             \end{minipage}\\
1267    \end{tabular}
1268    \vfill
1269    
1270    \newpage
1271    \vspace*{\fill}
1272    \begin{tabular}{llll}
1273    \hline\hline
1274     NAME & UNITS & LEVELS & DESCRIPTION \\
1275    \hline
1276    
1277    &\\
1278     SLP      &   $mb$  &    1
1279             &\begin{minipage}[t]{3in}
1280              {Time-averaged Sea-level Pressure}
1281             \end{minipage}\\
1282     CLDFRC  & $0-1$ &    1
1283             &\begin{minipage}[t]{3in}
1284              {Total Cloud Fraction}
1285             \end{minipage}\\
1286     TPW     & $gm/cm^2$ &    1
1287             &\begin{minipage}[t]{3in}
1288              {Precipitable water}
1289             \end{minipage}\\
1290     U2M     & $m/sec$ &    1
1291             &\begin{minipage}[t]{3in}
1292              {U-Wind at 2 meters}
1293             \end{minipage}\\
1294     V2M     & $m/sec$ &    1
1295             &\begin{minipage}[t]{3in}
1296              {V-Wind at 2 meters}
1297             \end{minipage}\\
1298     T2M     & $deg$ &    1
1299             &\begin{minipage}[t]{3in}
1300              {Temperature at 2 meters}
1301             \end{minipage}\\
1302     Q2M     & $g/kg$ &    1
1303             &\begin{minipage}[t]{3in}
1304              {Specific Humidity at 2 meters}
1305             \end{minipage}\\
1306     U10M    & $m/sec$ &    1
1307             &\begin{minipage}[t]{3in}
1308              {U-Wind at 10 meters}
1309             \end{minipage}\\
1310     V10M    & $m/sec$ &    1
1311             &\begin{minipage}[t]{3in}
1312              {V-Wind at 10 meters}
1313             \end{minipage}\\
1314     T10M    & $deg$ &    1
1315             &\begin{minipage}[t]{3in}
1316              {Temperature at 10 meters}
1317             \end{minipage}\\
1318     Q10M    & $g/kg$ &    1
1319             &\begin{minipage}[t]{3in}
1320              {Specific Humidity at 10 meters}
1321             \end{minipage}\\
1322     DTRAIN  & $kg/m^2$ &    Nrphys
1323             &\begin{minipage}[t]{3in}
1324              {Detrainment Cloud Mass Flux}
1325             \end{minipage}\\
1326     QFILL   & $g/kg/day$ &    Nrphys
1327             &\begin{minipage}[t]{3in}
1328              {Filling of negative specific humidity}
1329             \end{minipage}\\
1330    \end{tabular}
1331    \vspace{1.5in}
1332    \vfill
1333    
1334    \newpage
1335    \vspace*{\fill}
1336    \begin{tabular}{llll}
1337    \hline\hline
1338     NAME & UNITS & LEVELS & DESCRIPTION \\
1339    \hline
1340    
1341    &\\
1342     DTCONV   & $deg/sec$ & Nr
1343             &\begin{minipage}[t]{3in}
1344              {Temp Change due to Convection}
1345             \end{minipage}\\
1346     DQCONV   & $g/kg/sec$ & Nr
1347             &\begin{minipage}[t]{3in}
1348              {Specific Humidity Change due to Convection}
1349             \end{minipage}\\
1350     RELHUM   & $percent$ & Nr
1351             &\begin{minipage}[t]{3in}
1352              {Relative Humidity}
1353             \end{minipage}\\
1354     PRECLS   & $g/m^2/sec$ & 1
1355             &\begin{minipage}[t]{3in}
1356              {Large Scale Precipitation}
1357             \end{minipage}\\
1358     ENPREC   & $J/g$ & 1
1359             &\begin{minipage}[t]{3in}
1360              {Energy of Precipitation (snow, rain Temp)}
1361             \end{minipage}\\
1362    \end{tabular}
1363    \vspace{1.5in}
1364    \vfill
1365    
1366    \newpage
1367    
1368    Fizhi Diagnostic Description:
1369    
1370    In this section we list and describe the diagnostic quantities available within the
1371    GCM.  The diagnostics are listed in the order that they appear in the
1372    Diagnostic Menu, Section \ref{sec:pkg:fizhi:diagnostics}.
1373    In all cases, each diagnostic as currently archived on the output datasets
1374    is time-averaged over its diagnostic output frequency:
1375    
1376    \[
1377    {\bf DIAGNOSTIC} = {1 \over TTOT} \sum_{t=1}^{t=TTOT} diag(t)
1378    \]
1379    where $TTOT = {{\bf NQDIAG} \over \Delta t}$, {\bf NQDIAG} is the
1380    output frequency of the diagnostic, and $\Delta t$ is
1381    the timestep over which the diagnostic is updated.  
1382    
1383    { \underline {UFLUX} Surface Zonal Wind Stress on the Atmosphere ($Newton/m^2$) }
1384    
1385    The zonal wind stress is the turbulent flux of zonal momentum from
1386    the surface.
1387    \[
1388    {\bf UFLUX} =  - \rho C_D W_s u \hspace{1cm}where: \hspace{.2cm}C_D = C^2_u
1389    \]
1390    where $\rho$ = the atmospheric density at the surface, $C_{D}$ is the surface
1391    drag coefficient, $C_u$ is the dimensionless surface exchange coefficient for momentum
1392    (see diagnostic number 10), $W_s$ is the magnitude of the surface layer wind, and $u$ is
1393    the zonal wind in the lowest model layer.
1394    \\
1395    
1396    
1397    { \underline {VFLUX} Surface Meridional Wind Stress on the Atmosphere ($Newton/m^2$) }
1398    
1399    The meridional wind stress is the turbulent flux of meridional momentum from
1400    the surface.
1401    \[
1402    {\bf VFLUX} =  - \rho C_D W_s v \hspace{1cm}where: \hspace{.2cm}C_D = C^2_u
1403    \]
1404    where $\rho$ = the atmospheric density at the surface, $C_{D}$ is the surface
1405    drag coefficient, $C_u$ is the dimensionless surface exchange coefficient for momentum
1406    (see diagnostic number 10), $W_s$ is the magnitude of the surface layer wind, and $v$ is
1407    the meridional wind in the lowest model layer.
1408    \\
1409    
1410    { \underline {HFLUX} Surface Flux of Sensible Heat ($Watts/m^2$) }
1411    
1412    The turbulent flux of sensible heat from the surface to the atmosphere is a function of the
1413    gradient of virtual potential temperature and the eddy exchange coefficient:
1414    \[
1415    {\bf HFLUX} =  P^{\kappa}\rho c_{p} C_{H} W_s (\theta_{surface} - \theta_{Nrphys})
1416    \hspace{1cm}where: \hspace{.2cm}C_H = C_u C_t
1417    \]
1418    where $\rho$ = the atmospheric density at the surface, $c_{p}$ is the specific
1419    heat of air, $C_{H}$ is the dimensionless surface heat transfer coefficient, $W_s$ is the
1420    magnitude of the surface layer wind, $C_u$ is the dimensionless surface exchange coefficient
1421    for momentum (see diagnostic number 10), $C_t$ is the dimensionless surface exchange coefficient
1422    for heat and moisture (see diagnostic number 9), and $\theta$ is the potential temperature
1423    at the surface and at the bottom model level.
1424    \\
1425    
1426    
1427    { \underline {EFLUX} Surface Flux of Latent Heat ($Watts/m^2$) }
1428    
1429    The turbulent flux of latent heat from the surface to the atmosphere is a function of the
1430    gradient of moisture, the potential evapotranspiration fraction and the eddy exchange coefficient:
1431    \[
1432    {\bf EFLUX} =  \rho \beta L C_{H} W_s (q_{surface} - q_{Nrphys})
1433    \hspace{1cm}where: \hspace{.2cm}C_H = C_u C_t
1434    \]
1435    where $\rho$ = the atmospheric density at the surface, $\beta$ is the fraction of
1436    the potential evapotranspiration actually evaporated, L is the latent
1437    heat of evaporation, $C_{H}$ is the dimensionless surface heat transfer coefficient, $W_s$ is the
1438    magnitude of the surface layer wind, $C_u$ is the dimensionless surface exchange coefficient
1439    for momentum (see diagnostic number 10), $C_t$ is the dimensionless surface exchange coefficient
1440    for heat and moisture (see diagnostic number 9), and $q_{surface}$ and $q_{Nrphys}$ are the specific
1441    humidity at the surface and at the bottom model level, respectively.
1442    \\
1443    
1444    { \underline {QICE} Heat Conduction Through Sea Ice ($Watts/m^2$) }
1445    
1446    Over sea ice there is an additional source of energy at the surface due to the heat
1447    conduction from the relatively warm ocean through the sea ice. The heat conduction
1448    through sea ice represents an additional energy source term for the ground temperature equation.
1449    
1450    \[
1451    {\bf QICE} = {C_{ti} \over {H_i}} (T_i-T_g)
1452    \]
1453    
1454    where $C_{ti}$ is the thermal conductivity of ice, $H_i$ is the ice thickness, assumed to
1455    be $3 \hspace{.1cm} m$ where sea ice is present, $T_i$ is 273 degrees Kelvin, and
1456    $T_g$ is the temperature of the sea ice.
1457    
1458    NOTE: QICE is not available through model version 5.3, but is available in subsequent versions.
1459    \\
1460    
1461    
1462    { \underline {RADLWG} Net upward Longwave Flux at the surface ($Watts/m^2$)}
1463    
1464    \begin{eqnarray*}
1465    {\bf RADLWG} & =  & F_{LW,Nrphys+1}^{Net} \\
1466                 & =  & F_{LW,Nrphys+1}^\uparrow - F_{LW,Nrphys+1}^\downarrow
1467    \end{eqnarray*}
1468    \\
1469    where Nrphys+1 indicates the lowest model edge-level, or $p = p_{surf}$.
1470    $F_{LW}^\uparrow$ is
1471    the upward Longwave flux and $F_{LW}^\downarrow$ is the downward Longwave flux.
1472    \\
1473    
1474    { \underline {RADSWG} Net downard shortwave Flux at the surface ($Watts/m^2$)}
1475    
1476    \begin{eqnarray*}
1477    {\bf RADSWG} & =  & F_{SW,Nrphys+1}^{Net} \\
1478                 & =  & F_{SW,Nrphys+1}^\downarrow - F_{SW,Nrphys+1}^\uparrow
1479    \end{eqnarray*}
1480    \\
1481    where Nrphys+1 indicates the lowest model edge-level, or $p = p_{surf}$.
1482    $F_{SW}^\downarrow$ is
1483    the downward Shortwave flux and $F_{SW}^\uparrow$ is the upward Shortwave flux.
1484    \\
1485    
1486    
1487    \noindent
1488    { \underline {RI} Richardson Number} ($dimensionless$)
1489    
1490    \noindent
1491    The non-dimensional stability indicator is the ratio of the buoyancy to the shear:
1492    \[
1493    {\bf RI} = { { {g \over \theta_v} \pp {\theta_v}{z} } \over { (\pp{u}{z})^2 + (\pp{v}{z})^2 } }
1494     =  {  {c_p \pp{\theta_v}{z} \pp{P^ \kappa}{z} } \over { (\pp{u}{z})^2 + (\pp{v}{z})^2 } }
1495    \]
1496    \\
1497    where we used the hydrostatic equation:
1498    \[
1499    {\pp{\Phi}{P^ \kappa}} = c_p \theta_v
1500    \]
1501    Negative values indicate unstable buoyancy {\bf{AND}} shear, small positive values ($<0.4$)
1502    indicate dominantly unstable shear, and large positive values indicate dominantly stable
1503    stratification.
1504    \\
1505    
1506    \noindent
1507    { \underline {CT}  Surface Exchange Coefficient for Temperature and Moisture ($dimensionless$) }
1508    
1509    \noindent
1510    The surface exchange coefficient is obtained from the similarity functions for the stability
1511     dependant flux profile relationships:
1512    \[
1513    {\bf CT} = -{( {\overline{w^{\prime}\theta^{\prime}}}) \over {u_* \Delta \theta }} =
1514    -{( {\overline{w^{\prime}q^{\prime}}}) \over {u_* \Delta q }} =
1515    { k \over { (\psi_{h} + \psi_{g}) } }
1516    \]
1517    where $\psi_h$ is the surface layer non-dimensional temperature change and $\psi_g$ is the
1518    viscous sublayer non-dimensional temperature or moisture change:
1519    \[
1520    \psi_{h} = {\int_{\zeta_{0}}^{\zeta} {\phi_{h} \over \zeta} d \zeta} \hspace{1cm} and
1521    \hspace{1cm} \psi_{g} = { 0.55 (Pr^{2/3} - 0.2) \over \nu^{1/2} }
1522    (h_{0}u_{*} - h_{0_{ref}}u_{*_{ref}})^{1/2}
1523    \]
1524    and:
1525    $h_{0} = 30z_{0}$ with a maximum value over land of 0.01
1526    
1527    \noindent
1528    $\phi_h$ is the similarity function of $\zeta$, which expresses the stability dependance of
1529    the temperature and moisture gradients, specified differently for stable and unstable
1530    layers according to \cite{helfschu:95}. k is the Von Karman constant, $\zeta$ is the
1531    non-dimensional stability parameter, Pr is the Prandtl number for air, $\nu$ is the molecular
1532    viscosity, $z_{0}$ is the surface roughness length, $u_*$ is the surface stress velocity
1533    (see diagnostic number 67), and the subscript ref refers to a reference value.
1534    \\
1535    
1536    \noindent
1537    { \underline {CU}  Surface Exchange Coefficient for Momentum ($dimensionless$) }
1538    
1539    \noindent
1540    The surface exchange coefficient is obtained from the similarity functions for the stability
1541     dependant flux profile relationships:
1542    \[
1543    {\bf CU} = {u_* \over W_s} = { k \over \psi_{m} }
1544    \]
1545    where $\psi_m$ is the surface layer non-dimensional wind shear:
1546    \[
1547    \psi_{m} = {\int_{\zeta_{0}}^{\zeta} {\phi_{m} \over \zeta} d \zeta}
1548    \]
1549    \noindent
1550    $\phi_m$ is the similarity function of $\zeta$, which expresses the stability dependance of
1551    the temperature and moisture gradients, specified differently for stable and unstable layers
1552    according to \cite{helfschu:95}. k is the Von Karman constant, $\zeta$ is the
1553    non-dimensional stability parameter, $u_*$ is the surface stress velocity
1554    (see diagnostic number 67), and $W_s$ is the magnitude of the surface layer wind.
1555    \\
1556    
1557    \noindent
1558    { \underline {ET}  Diffusivity Coefficient for Temperature and Moisture ($m^2/sec$) }
1559    
1560    \noindent
1561    In the level 2.5 version of the Mellor-Yamada (1974) hierarchy, the turbulent heat or
1562    moisture flux for the atmosphere above the surface layer can be expressed as a turbulent
1563    diffusion coefficient $K_h$ times the negative of the gradient of potential temperature
1564    or moisture. In the \cite{helflab:88} adaptation of this closure, $K_h$
1565    takes the form:
1566    \[
1567    {\bf ET} = K_h = -{( {\overline{w^{\prime}\theta_v^{\prime}}}) \over {\pp{\theta_v}{z}} }
1568     = \left\{ \begin{array}{l@{\quad\mbox{for}\quad}l} q \, \ell \, S_H(G_M,G_H) & \mbox{decaying turbulence}
1569    \\ { q^2 \over {q_e} } \, \ell \, S_{H}(G_{M_e},G_{H_e}) & \mbox{growing turbulence} \end{array} \right.
1570    \]
1571    where $q$ is the turbulent velocity, or $\sqrt{2*turbulent \hspace{.2cm} kinetic \hspace{.2cm}
1572    energy}$, $q_e$ is the turbulence velocity derived from the more simple level 2.0 model,
1573    which describes equilibrium turbulence, $\ell$ is the master length scale related to the layer
1574    depth,
1575    $S_H$ is a function of $G_H$ and $G_M$, the dimensionless buoyancy and
1576    wind shear parameters, respectively, or a function of $G_{H_e}$ and $G_{M_e}$, the equilibrium
1577    dimensionless buoyancy and wind shear
1578    parameters.   Both $G_H$ and $G_M$, and their equilibrium values $G_{H_e}$ and $G_{M_e}$,
1579    are functions of the Richardson number.
1580    
1581    \noindent
1582    For the detailed equations and derivations of the modified level 2.5 closure scheme,
1583    see \cite{helflab:88}.
1584    
1585    \noindent
1586    In the surface layer, ${\bf {ET}}$ is the exchange coefficient for heat and moisture,
1587    in units of $m/sec$, given by:
1588    \[
1589    {\bf ET_{Nrphys}} =  C_t * u_* = C_H W_s
1590    \]
1591    \noindent
1592    where $C_t$ is the dimensionless exchange coefficient for heat and moisture from the
1593    surface layer similarity functions (see diagnostic number 9), $u_*$ is the surface
1594    friction velocity (see diagnostic number 67), $C_H$ is the heat transfer coefficient,
1595    and $W_s$ is the magnitude of the surface layer wind.
1596    \\
1597    
1598    \noindent
1599    { \underline {EU}  Diffusivity Coefficient for Momentum ($m^2/sec$) }
1600    
1601    \noindent  
1602    In the level 2.5 version of the Mellor-Yamada (1974) hierarchy, the turbulent heat
1603    momentum flux for the atmosphere above the surface layer can be expressed as a turbulent
1604    diffusion coefficient $K_m$ times the negative of the gradient of the u-wind.
1605    In the \cite{helflab:88} adaptation of this closure, $K_m$
1606    takes the form:
1607    \[
1608    {\bf EU} = K_m = -{( {\overline{u^{\prime}w^{\prime}}}) \over {\pp{U}{z}} }
1609     = \left\{ \begin{array}{l@{\quad\mbox{for}\quad}l} q \, \ell \, S_M(G_M,G_H) & \mbox{decaying turbulence}
1610    \\ { q^2 \over {q_e} } \, \ell \, S_{M}(G_{M_e},G_{H_e}) & \mbox{growing turbulence} \end{array} \right.
1611    \]
1612    \noindent
1613    where $q$ is the turbulent velocity, or $\sqrt{2*turbulent \hspace{.2cm} kinetic \hspace{.2cm}
1614    energy}$, $q_e$ is the turbulence velocity derived from the more simple level 2.0 model,
1615    which describes equilibrium turbulence, $\ell$ is the master length scale related to the layer
1616    depth,
1617    $S_M$ is a function of $G_H$ and $G_M$, the dimensionless buoyancy and
1618    wind shear parameters, respectively, or a function of $G_{H_e}$ and $G_{M_e}$, the equilibrium
1619    dimensionless buoyancy and wind shear
1620    parameters.   Both $G_H$ and $G_M$, and their equilibrium values $G_{H_e}$ and $G_{M_e}$,
1621    are functions of the Richardson number.
1622    
1623    \noindent
1624    For the detailed equations and derivations of the modified level 2.5 closure scheme,
1625    see \cite{helflab:88}.
1626    
1627    \noindent
1628    In the surface layer, ${\bf {EU}}$ is the exchange coefficient for momentum,
1629    in units of $m/sec$, given by:
1630    \[
1631    {\bf EU_{Nrphys}} = C_u * u_* = C_D W_s
1632    \]
1633    \noindent
1634    where $C_u$ is the dimensionless exchange coefficient for momentum from the surface layer
1635    similarity functions (see diagnostic number 10), $u_*$ is the surface friction velocity
1636    (see diagnostic number 67), $C_D$ is the surface drag coefficient, and $W_s$ is the
1637    magnitude of the surface layer wind.
1638    \\
1639    
1640    \noindent
1641    { \underline {TURBU}  Zonal U-Momentum changes due to Turbulence ($m/sec/day$) }
1642    
1643    \noindent
1644    The tendency of U-Momentum due to turbulence is written:
1645    \[
1646    {\bf TURBU} = {\pp{u}{t}}_{turb} = {\pp{}{z} }{(- \overline{u^{\prime}w^{\prime}})}
1647     = {\pp{}{z} }{(K_m \pp{u}{z})}
1648    \]
1649    
1650    \noindent
1651    The Helfand and Labraga level 2.5 scheme models the turbulent
1652    flux of u-momentum in terms of $K_m$, and the equation has the form of a diffusion
1653    equation.
1654    
1655    \noindent
1656    { \underline {TURBV}  Meridional V-Momentum changes due to Turbulence ($m/sec/day$) }
1657    
1658    \noindent
1659    The tendency of V-Momentum due to turbulence is written:
1660    \[
1661    {\bf TURBV} = {\pp{v}{t}}_{turb} = {\pp{}{z} }{(- \overline{v^{\prime}w^{\prime}})}
1662     = {\pp{}{z} }{(K_m \pp{v}{z})}
1663    \]
1664    
1665    \noindent
1666    The Helfand and Labraga level 2.5 scheme models the turbulent
1667    flux of v-momentum in terms of $K_m$, and the equation has the form of a diffusion
1668    equation.
1669    \\
1670    
1671    \noindent
1672    { \underline {TURBT}  Temperature changes due to Turbulence ($deg/day$) }
1673    
1674    \noindent
1675    The tendency of temperature due to turbulence is written:
1676    \[
1677    {\bf TURBT} = {\pp{T}{t}} = P^{\kappa}{\pp{\theta}{t}}_{turb} =
1678    P^{\kappa}{\pp{}{z} }{(- \overline{w^{\prime}\theta^{\prime}})}
1679     = P^{\kappa}{\pp{}{z} }{(K_h \pp{\theta_v}{z})}
1680    \]
1681    
1682    \noindent
1683    The Helfand and Labraga level 2.5 scheme models the turbulent
1684    flux of temperature in terms of $K_h$, and the equation has the form of a diffusion
1685    equation.
1686    \\
1687    
1688    \noindent
1689    { \underline {TURBQ}  Specific Humidity changes due to Turbulence ($g/kg/day$) }
1690    
1691    \noindent
1692    The tendency of specific humidity due to turbulence is written:
1693    \[
1694    {\bf TURBQ} = {\pp{q}{t}}_{turb} = {\pp{}{z} }{(- \overline{w^{\prime}q^{\prime}})}
1695     = {\pp{}{z} }{(K_h \pp{q}{z})}
1696    \]
1697    
1698    \noindent
1699    The Helfand and Labraga level 2.5 scheme models the turbulent
1700    flux of temperature in terms of $K_h$, and the equation has the form of a diffusion
1701    equation.
1702    \\
1703    
1704    \noindent
1705    { \underline {MOISTT} Temperature Changes Due to Moist Processes ($deg/day$) }
1706    
1707    \noindent
1708    \[
1709    {\bf MOISTT} = \left. {\pp{T}{t}}\right|_{c} + \left. {\pp{T}{t}} \right|_{ls}
1710    \]
1711    where:
1712    \[
1713    \left.{\pp{T}{t}}\right|_{c} = R \sum_i \left( \alpha { m_B \over c_p} \Gamma_s \right)_i
1714    \hspace{.4cm} and
1715    \hspace{.4cm} \left.{\pp{T}{t}}\right|_{ls} = {L \over c_p } (q^*-q)
1716    \]
1717    and
1718    \[
1719    \Gamma_s = g \eta \pp{s}{p}
1720    \]
1721    
1722    \noindent
1723    The subscript $c$ refers to convective processes, while the subscript $ls$ refers to large scale
1724    precipitation processes, or supersaturation rain.
1725    The summation refers to contributions from each cloud type called by RAS.  
1726    The dry static energy is given
1727    as $s$, the convective cloud base mass flux is given as $m_B$, and the cloud entrainment is
1728    given as $\eta$, which are explicitly defined in Section \ref{sec:fizhi:mc},
1729    the description of the convective parameterization.  The fractional adjustment, or relaxation
1730    parameter, for each cloud type is given as $\alpha$, while
1731    $R$ is the rain re-evaporation adjustment.
1732    \\
1733    
1734    \noindent
1735    { \underline {MOISTQ} Specific Humidity Changes Due to Moist Processes ($g/kg/day$) }
1736    
1737    \noindent
1738    \[
1739    {\bf MOISTQ} = \left. {\pp{q}{t}}\right|_{c} + \left. {\pp{q}{t}} \right|_{ls}
1740    \]
1741    where:
1742    \[
1743    \left.{\pp{q}{t}}\right|_{c} = R \sum_i \left( \alpha { m_B \over {L}}(\Gamma_h-\Gamma_s) \right)_i
1744    \hspace{.4cm} and
1745    \hspace{.4cm} \left.{\pp{q}{t}}\right|_{ls} = (q^*-q)
1746    \]
1747    and
1748    \[
1749    \Gamma_s = g \eta \pp{s}{p}\hspace{.4cm} and \hspace{.4cm}\Gamma_h = g \eta \pp{h}{p}
1750    \]
1751    \noindent
1752    The subscript $c$ refers to convective processes, while the subscript $ls$ refers to large scale
1753    precipitation processes, or supersaturation rain.
1754    The summation refers to contributions from each cloud type called by RAS.  
1755    The dry static energy is given as $s$,
1756    the moist static energy is given as $h$,
1757    the convective cloud base mass flux is given as $m_B$, and the cloud entrainment is
1758    given as $\eta$, which are explicitly defined in Section \ref{sec:fizhi:mc},
1759    the description of the convective parameterization.  The fractional adjustment, or relaxation
1760    parameter, for each cloud type is given as $\alpha$, while
1761    $R$ is the rain re-evaporation adjustment.
1762    \\
1763    
1764    \noindent
1765    { \underline {RADLW} Heating Rate due to Longwave Radiation ($deg/day$) }
1766    
1767    \noindent
1768    The net longwave heating rate is calculated as the vertical divergence of the
1769    net terrestrial radiative fluxes.
1770    Both the clear-sky and cloudy-sky longwave fluxes are computed within the
1771    longwave routine.
1772    The subroutine calculates the clear-sky flux, $F^{clearsky}_{LW}$, first.
1773    For a given cloud fraction,
1774    the clear line-of-sight probability $C(p,p^{\prime})$ is computed from the current level pressure $p$
1775    to the model top pressure, $p^{\prime} = p_{top}$, and the model surface pressure, $p^{\prime} = p_{surf}$,
1776    for the upward and downward radiative fluxes.
1777    (see Section \ref{sec:fizhi:radcloud}).
1778    The cloudy-sky flux is then obtained as:
1779      
1780    \noindent
1781    \[
1782    F_{LW} = C(p,p') \cdot F^{clearsky}_{LW},
1783    \]
1784    
1785    \noindent
1786    Finally, the net longwave heating rate is calculated as the vertical divergence of the
1787    net terrestrial radiative fluxes:
1788    \[
1789    \pp{\rho c_p T}{t} = - {\partial \over \partial z} F_{LW}^{NET} ,
1790    \]
1791    or
1792    \[
1793    {\bf RADLW} = \frac{g}{c_p \pi} {\partial \over \partial \sigma} F_{LW}^{NET} .
1794    \]
1795    
1796    \noindent
1797    where $g$ is the accelation due to gravity,
1798    $c_p$ is the heat capacity of air at constant pressure,
1799    and
1800    \[
1801    F_{LW}^{NET} = F_{LW}^\uparrow - F_{LW}^\downarrow
1802    \]
1803    \\
1804    
1805    
1806    \noindent
1807    { \underline {RADSW} Heating Rate due to Shortwave Radiation ($deg/day$) }
1808    
1809    \noindent
1810    The net Shortwave heating rate is calculated as the vertical divergence of the
1811    net solar radiative fluxes.
1812    The clear-sky and cloudy-sky shortwave fluxes are calculated separately.
1813    For the clear-sky case, the shortwave fluxes and heating rates are computed with
1814    both CLMO (maximum overlap cloud fraction) and
1815    CLRO (random overlap cloud fraction) set to zero (see Section \ref{sec:fizhi:radcloud}).
1816    The shortwave routine is then called a second time, for the cloudy-sky case, with the
1817    true time-averaged cloud fractions CLMO
1818    and CLRO being used.  In all cases, a normalized incident shortwave flux is used as
1819    input at the top of the atmosphere.
1820    
1821    \noindent
1822    The heating rate due to Shortwave Radiation under cloudy skies is defined as:
1823    \[
1824    \pp{\rho c_p T}{t} = - {\partial \over \partial z} F(cloudy)_{SW}^{NET} \cdot {\rm RADSWT},
1825    \]
1826    or
1827    \[
1828    {\bf RADSW} = \frac{g}{c_p \pi} {\partial \over \partial \sigma} F(cloudy)_{SW}^{NET}\cdot {\rm RADSWT} .
1829    \]
1830    
1831    \noindent
1832    where $g$ is the accelation due to gravity,
1833    $c_p$ is the heat capacity of air at constant pressure, RADSWT is the true incident
1834    shortwave radiation at the top of the atmosphere (See Diagnostic \#48), and
1835    \[
1836    F(cloudy)_{SW}^{Net} = F(cloudy)_{SW}^\uparrow - F(cloudy)_{SW}^\downarrow
1837    \]
1838    \\
1839    
1840    \noindent
1841    { \underline {PREACC} Total (Large-scale + Convective) Accumulated Precipition ($mm/day$) }
1842    
1843    \noindent
1844    For a change in specific humidity due to moist processes, $\Delta q_{moist}$,
1845    the vertical integral or total precipitable amount is given by:  
1846    \[
1847    {\bf PREACC} = \int_{surf}^{top} \rho \Delta q_{moist} dz = - \int_{surf}^{top} \Delta  q_{moist}
1848    {dp \over g} = {1 \over g} \int_0^1 \Delta q_{moist} dp
1849    \]
1850    \\
1851    
1852    \noindent
1853    A precipitation rate is defined as the vertically integrated moisture adjustment per Moist Processes
1854    time step, scaled to $mm/day$.
1855    \\
1856    
1857    \noindent
1858    { \underline {PRECON} Convective Precipition ($mm/day$) }
1859    
1860    \noindent
1861    For a change in specific humidity due to sub-grid scale cumulus convective processes, $\Delta q_{cum}$,
1862    the vertical integral or total precipitable amount is given by:  
1863    \[
1864    {\bf PRECON} = \int_{surf}^{top} \rho \Delta q_{cum} dz = - \int_{surf}^{top} \Delta  q_{cum}
1865    {dp \over g} = {1 \over g} \int_0^1 \Delta q_{cum} dp
1866    \]
1867    \\
1868    
1869    \noindent
1870    A precipitation rate is defined as the vertically integrated moisture adjustment per Moist Processes
1871    time step, scaled to $mm/day$.
1872    \\
1873    
1874    \noindent
1875    { \underline {TUFLUX}  Turbulent Flux of U-Momentum ($Newton/m^2$) }
1876    
1877    \noindent
1878    The turbulent flux of u-momentum is calculated for $diagnostic \hspace{.2cm} purposes
1879     \hspace{.2cm} only$ from the eddy coefficient for momentum:
1880    
1881    \[
1882    {\bf TUFLUX} =  {\rho } {(\overline{u^{\prime}w^{\prime}})} =  
1883    {\rho } {(- K_m \pp{U}{z})}
1884    \]
1885    
1886    \noindent
1887    where $\rho$ is the air density, and $K_m$ is the eddy coefficient.
1888    \\
1889    
1890    \noindent
1891    { \underline {TVFLUX}  Turbulent Flux of V-Momentum ($Newton/m^2$) }
1892    
1893    \noindent
1894    The turbulent flux of v-momentum is calculated for $diagnostic \hspace{.2cm} purposes
1895    \hspace{.2cm} only$ from the eddy coefficient for momentum:
1896    
1897    \[
1898    {\bf TVFLUX} =  {\rho } {(\overline{v^{\prime}w^{\prime}})} =
1899     {\rho } {(- K_m \pp{V}{z})}
1900    \]
1901    
1902    \noindent
1903    where $\rho$ is the air density, and $K_m$ is the eddy coefficient.
1904    \\
1905    
1906    
1907    \noindent
1908    { \underline {TTFLUX}  Turbulent Flux of Sensible Heat ($Watts/m^2$) }
1909    
1910    \noindent
1911    The turbulent flux of sensible heat is calculated for $diagnostic \hspace{.2cm} purposes
1912    \hspace{.2cm} only$ from the eddy coefficient for heat and moisture:
1913    
1914    \noindent
1915    \[
1916    {\bf TTFLUX} = c_p {\rho }  
1917    P^{\kappa}{(\overline{w^{\prime}\theta^{\prime}})}
1918     = c_p  {\rho } P^{\kappa}{(- K_h \pp{\theta_v}{z})}
1919    \]
1920    
1921    \noindent
1922    where $\rho$ is the air density, and $K_h$ is the eddy coefficient.
1923    \\
1924    
1925    
1926    \noindent
1927    { \underline {TQFLUX}  Turbulent Flux of Latent Heat ($Watts/m^2$) }
1928    
1929    \noindent
1930    The turbulent flux of latent heat is calculated for $diagnostic \hspace{.2cm} purposes
1931    \hspace{.2cm} only$ from the eddy coefficient for heat and moisture:
1932    
1933    \noindent
1934    \[
1935    {\bf TQFLUX} = {L {\rho } (\overline{w^{\prime}q^{\prime}})} =
1936    {L {\rho }(- K_h \pp{q}{z})}
1937    \]
1938    
1939    \noindent
1940    where $\rho$ is the air density, and $K_h$ is the eddy coefficient.
1941    \\
1942    
1943    
1944    \noindent
1945    { \underline {CN}  Neutral Drag Coefficient ($dimensionless$) }
1946    
1947    \noindent
1948    The drag coefficient for momentum obtained by assuming a neutrally stable surface layer:
1949    \[
1950    {\bf CN} = { k \over { \ln({h \over {z_0}})} }
1951    \]
1952    
1953    \noindent
1954    where $k$ is the Von Karman constant, $h$ is the height of the surface layer, and
1955    $z_0$ is the surface roughness.
1956    
1957    \noindent
1958    NOTE: CN is not available through model version 5.3, but is available in subsequent
1959    versions.
1960    \\
1961    
1962    \noindent
1963    { \underline {WINDS}  Surface Wind Speed ($meter/sec$) }
1964    
1965    \noindent
1966    The surface wind speed is calculated for the last internal turbulence time step:
1967    \[
1968    {\bf WINDS} = \sqrt{u_{Nrphys}^2 + v_{Nrphys}^2}
1969    \]
1970    
1971    \noindent
1972    where the subscript $Nrphys$ refers to the lowest model level.
1973    \\
1974    
1975    \noindent
1976    { \underline {DTSRF}  Air/Surface Virtual Temperature Difference ($deg \hspace{.1cm} K$) }
1977    
1978    \noindent
1979    The air/surface virtual temperature difference measures the stability of the surface layer:
1980    \[
1981    {\bf DTSRF} = (\theta_{v{Nrphys+1}} - \theta{v_{Nrphys}}) P^{\kappa}_{surf}
1982    \]
1983    \noindent
1984    where
1985    \[
1986    \theta_{v{Nrphys+1}} = { T_g \over {P^{\kappa}_{surf}} } (1 + .609 q_{Nrphys+1}) \hspace{1cm}
1987    and \hspace{1cm} q_{Nrphys+1} = q_{Nrphys} + \beta(q^*(T_g,P_s) - q_{Nrphys})
1988    \]
1989    
1990    \noindent
1991    $\beta$ is the surface potential evapotranspiration coefficient ($\beta=1$ over oceans),
1992    $q^*(T_g,P_s)$ is the saturation specific humidity at the ground temperature
1993    and surface pressure, level $Nrphys$ refers to the lowest model level and level $Nrphys+1$
1994    refers to the surface.
1995    \\
1996    
1997    
1998    \noindent
1999    { \underline {TG}  Ground Temperature ($deg \hspace{.1cm} K$) }
2000    
2001    \noindent
2002    The ground temperature equation is solved as part of the turbulence package
2003    using a backward implicit time differencing scheme:
2004    \[
2005    {\bf TG} \hspace{.1cm} is \hspace{.1cm} obtained \hspace{.1cm} from: \hspace{.1cm}
2006    C_g\pp{T_g}{t} = R_{sw} - R_{lw} + Q_{ice} - H - LE
2007    \]
2008    
2009    \noindent
2010    where $R_{sw}$ is the net surface downward shortwave radiative flux, $R_{lw}$ is the
2011    net surface upward longwave radiative flux, $Q_{ice}$ is the heat conduction through
2012    sea ice, $H$ is the upward sensible heat flux, $LE$ is the upward latent heat
2013    flux, and $C_g$ is the total heat capacity of the ground.
2014    $C_g$ is obtained by solving a heat diffusion equation
2015    for the penetration of the diurnal cycle into the ground (\cite{black:77}), and is given by:
2016    \[
2017    C_g = \sqrt{ {\lambda C_s \over {2 \omega} } } = \sqrt{(0.386 + 0.536W + 0.15W^2)2x10^{-3}
2018    { 86400. \over {2 \pi} } } \, \, .
2019    \]
2020    \noindent
2021    Here, the thermal conductivity, $\lambda$, is equal to $2x10^{-3}$ ${ly\over{ sec}}
2022    {cm \over {^oK}}$,
2023    the angular velocity of the earth, $\omega$, is written as $86400$ $sec/day$ divided
2024    by $2 \pi$ $radians/
2025    day$, and the expression for $C_s$, the heat capacity per unit volume at the surface,
2026    is a function of the ground wetness, $W$.
2027    \\
2028    
2029    \noindent
2030    { \underline {TS}  Surface Temperature ($deg \hspace{.1cm} K$) }
2031    
2032    \noindent
2033    The surface temperature estimate is made by assuming that the model's lowest
2034    layer is well-mixed, and therefore that $\theta$ is constant in that layer.
2035    The surface temperature is therefore:
2036    \[
2037    {\bf TS} = \theta_{Nrphys} P^{\kappa}_{surf}
2038    \]
2039    \\
2040    
2041    \noindent
2042    { \underline {DTG}  Surface Temperature Adjustment ($deg \hspace{.1cm} K$) }
2043    
2044    \noindent
2045    The change in surface temperature from one turbulence time step to the next, solved
2046    using the Ground Temperature Equation (see diagnostic number 30) is calculated:
2047    \[
2048    {\bf DTG} = {T_g}^{n} - {T_g}^{n-1}
2049    \]
2050    
2051    \noindent
2052    where superscript $n$ refers to the new, updated time level, and the superscript $n-1$
2053    refers to the value at the previous turbulence time level.
2054    \\
2055    
2056    \noindent
2057    { \underline {QG}  Ground Specific Humidity ($g/kg$) }
2058    
2059    \noindent
2060    The ground specific humidity is obtained by interpolating between the specific
2061    humidity at the lowest model level and the specific humidity of a saturated ground.
2062    The interpolation is performed using the potential evapotranspiration function:
2063    \[
2064    {\bf QG} = q_{Nrphys+1} = q_{Nrphys} + \beta(q^*(T_g,P_s) - q_{Nrphys})
2065    \]
2066    
2067    \noindent
2068    where $\beta$ is the surface potential evapotranspiration coefficient ($\beta=1$ over oceans),
2069    and $q^*(T_g,P_s)$ is the saturation specific humidity at the ground temperature and surface
2070    pressure.
2071    \\
2072    
2073    \noindent
2074    { \underline {QS}  Saturation Surface Specific Humidity ($g/kg$) }
2075    
2076    \noindent
2077    The surface saturation specific humidity is the saturation specific humidity at
2078    the ground temprature and surface pressure:
2079    \[
2080    {\bf QS} = q^*(T_g,P_s)
2081    \]
2082    \\
2083    
2084    \noindent
2085    { \underline {TGRLW} Instantaneous ground temperature used as input to the Longwave
2086     radiation subroutine (deg)}
2087    \[
2088    {\bf TGRLW}  = T_g(\lambda , \phi ,n)
2089    \]
2090    \noindent
2091    where $T_g$ is the model ground temperature at the current time step $n$.
2092    \\
2093    
2094    
2095    \noindent
2096    { \underline {ST4} Upward Longwave flux at the surface ($Watts/m^2$) }
2097    \[
2098    {\bf ST4} = \sigma T^4
2099    \]
2100    \noindent
2101    where $\sigma$ is the Stefan-Boltzmann constant and T is the temperature.
2102    \\
2103    
2104    \noindent
2105    { \underline {OLR} Net upward Longwave flux at $p=p_{top}$ ($Watts/m^2$) }
2106    \[
2107    {\bf OLR}  =  F_{LW,top}^{NET}
2108    \]
2109    \noindent
2110    where top indicates the top of the first model layer.
2111    In the GCM, $p_{top}$ = 0.0 mb.
2112    \\
2113    
2114    
2115    \noindent
2116    { \underline {OLRCLR} Net upward clearsky Longwave flux at $p=p_{top}$ ($Watts/m^2$) }
2117    \[
2118    {\bf OLRCLR}  =  F(clearsky)_{LW,top}^{NET}
2119    \]
2120    \noindent
2121    where top indicates the top of the first model layer.
2122    In the GCM, $p_{top}$ = 0.0 mb.
2123    \\
2124    
2125    \noindent
2126    { \underline {LWGCLR} Net upward clearsky Longwave flux at the surface ($Watts/m^2$) }
2127    
2128    \noindent
2129    \begin{eqnarray*}
2130    {\bf LWGCLR} & =  & F(clearsky)_{LW,Nrphys+1}^{Net} \\
2131                 & =  & F(clearsky)_{LW,Nrphys+1}^\uparrow - F(clearsky)_{LW,Nrphys+1}^\downarrow
2132    \end{eqnarray*}
2133    where Nrphys+1 indicates the lowest model edge-level, or $p = p_{surf}$.
2134    $F(clearsky)_{LW}^\uparrow$ is
2135    the upward clearsky Longwave flux and the $F(clearsky)_{LW}^\downarrow$ is the downward clearsky Longwave flux.
2136    \\
2137    
2138    \noindent
2139    { \underline {LWCLR} Heating Rate due to Clearsky Longwave Radiation ($deg/day$) }
2140    
2141    \noindent
2142    The net longwave heating rate is calculated as the vertical divergence of the
2143    net terrestrial radiative fluxes.
2144    Both the clear-sky and cloudy-sky longwave fluxes are computed within the
2145    longwave routine.
2146    The subroutine calculates the clear-sky flux, $F^{clearsky}_{LW}$, first.
2147    For a given cloud fraction,
2148    the clear line-of-sight probability $C(p,p^{\prime})$ is computed from the current level pressure $p$
2149    to the model top pressure, $p^{\prime} = p_{top}$, and the model surface pressure, $p^{\prime} = p_{surf}$,
2150    for the upward and downward radiative fluxes.
2151    (see Section \ref{sec:fizhi:radcloud}).
2152    The cloudy-sky flux is then obtained as:
2153      
2154    \noindent
2155    \[
2156    F_{LW} = C(p,p') \cdot F^{clearsky}_{LW},
2157    \]
2158    
2159    \noindent
2160    Thus, {\bf LWCLR} is defined as the net longwave heating rate due to the
2161    vertical divergence of the
2162    clear-sky longwave radiative flux:
2163    \[
2164    \pp{\rho c_p T}{t}_{clearsky} = - {\partial \over \partial z} F(clearsky)_{LW}^{NET} ,
2165    \]
2166    or
2167    \[
2168    {\bf LWCLR} = \frac{g}{c_p \pi} {\partial \over \partial \sigma} F(clearsky)_{LW}^{NET} .
2169    \]
2170    
2171    \noindent
2172    where $g$ is the accelation due to gravity,
2173    $c_p$ is the heat capacity of air at constant pressure,
2174    and
2175    \[
2176    F(clearsky)_{LW}^{Net} = F(clearsky)_{LW}^\uparrow - F(clearsky)_{LW}^\downarrow
2177    \]
2178    \\
2179    
2180    
2181    \noindent
2182    { \underline {TLW} Instantaneous temperature used as input to the Longwave
2183     radiation subroutine (deg)}
2184    \[
2185    {\bf TLW}  = T(\lambda , \phi ,level, n)
2186    \]
2187    \noindent
2188    where $T$ is the model temperature at the current time step $n$.
2189    \\
2190    
2191    
2192    \noindent
2193    { \underline {SHLW} Instantaneous specific humidity used as input to
2194     the Longwave radiation subroutine (kg/kg)}
2195    \[
2196    {\bf SHLW}  = q(\lambda , \phi , level , n)
2197    \]
2198    \noindent
2199    where $q$ is the model specific humidity at the current time step $n$.
2200    \\
2201    
2202    
2203    \noindent
2204    { \underline {OZLW} Instantaneous ozone used as input to
2205     the Longwave radiation subroutine (kg/kg)}
2206    \[
2207    {\bf OZLW}  = {\rm OZ}(\lambda , \phi , level , n)
2208    \]
2209    \noindent
2210    where $\rm OZ$ is the interpolated ozone data set from the climatological monthly
2211    mean zonally averaged ozone data set.
2212    \\
2213    
2214    
2215    \noindent
2216    { \underline {CLMOLW} Maximum Overlap cloud fraction used in LW Radiation ($0-1$) }
2217    
2218    \noindent
2219    {\bf CLMOLW} is the time-averaged maximum overlap cloud fraction that has been filled by the Relaxed
2220    Arakawa/Schubert Convection scheme and will be used in the Longwave Radiation algorithm.  These are
2221    convective clouds whose radiative characteristics are assumed to be correlated in the vertical.
2222    For a complete description of cloud/radiative interactions, see Section \ref{sec:fizhi:radcloud}.
2223    \[
2224    {\bf CLMOLW} = CLMO_{RAS,LW}(\lambda, \phi,  level )
2225    \]
2226    \\
2227    
2228    
2229    { \underline {CLDTOT} Total cloud fraction used in LW and SW Radiation ($0-1$) }
2230    
2231    {\bf CLDTOT} is the time-averaged total cloud fraction that has been filled by the Relaxed
2232    Arakawa/Schubert and Large-scale Convection schemes and will be used in the Longwave and Shortwave
2233    Radiation packages.
2234    For a complete description of cloud/radiative interactions, see Section \ref{sec:fizhi:radcloud}.
2235    \[
2236    {\bf CLDTOT} = F_{RAS} + F_{LS}
2237    \]
2238    \\
2239    where $F_{RAS}$ is the time-averaged cloud fraction due to sub-grid scale convection, and $F_{LS}$ is the
2240    time-averaged cloud fraction due to precipitating and non-precipitating large-scale moist processes.
2241    \\
2242    
2243    
2244    \noindent
2245    { \underline {CLMOSW} Maximum Overlap cloud fraction used in SW Radiation ($0-1$) }
2246    
2247    \noindent
2248    {\bf CLMOSW} is the time-averaged maximum overlap cloud fraction that has been filled by the Relaxed
2249    Arakawa/Schubert Convection scheme and will be used in the Shortwave Radiation algorithm.  These are
2250    convective clouds whose radiative characteristics are assumed to be correlated in the vertical.
2251    For a complete description of cloud/radiative interactions, see Section \ref{sec:fizhi:radcloud}.
2252    \[
2253    {\bf CLMOSW} = CLMO_{RAS,SW}(\lambda, \phi,  level )
2254    \]
2255    \\
2256    
2257    \noindent
2258    { \underline {CLROSW} Random Overlap cloud fraction used in SW Radiation ($0-1$) }
2259    
2260    \noindent
2261    {\bf CLROSW} is the time-averaged random overlap cloud fraction that has been filled by the Relaxed
2262    Arakawa/Schubert and Large-scale Convection schemes and will be used in the Shortwave
2263    Radiation algorithm.  These are
2264    convective and large-scale clouds whose radiative characteristics are not
2265    assumed to be correlated in the vertical.
2266    For a complete description of cloud/radiative interactions, see Section \ref{sec:fizhi:radcloud}.
2267    \[
2268    {\bf CLROSW} = CLRO_{RAS,Large Scale,SW}(\lambda, \phi,  level )
2269    \]
2270    \\
2271    
2272    \noindent
2273    { \underline {RADSWT} Incident Shortwave radiation at the top of the atmosphere ($Watts/m^2$) }
2274    \[
2275    {\bf RADSWT} = {\frac{S_0}{R_a^2}} \cdot cos \phi_z
2276    \]
2277    \noindent
2278    where $S_0$, is the extra-terrestial solar contant,
2279    $R_a$ is the earth-sun distance in Astronomical Units,
2280    and $cos \phi_z$ is the cosine of the zenith angle.
2281    It should be noted that {\bf RADSWT}, as well as
2282    {\bf OSR} and {\bf OSRCLR},
2283    are calculated at the top of the atmosphere (p=0 mb).  However, the
2284    {\bf OLR} and {\bf OLRCLR} diagnostics are currently
2285    calculated at $p= p_{top}$ (0.0 mb for the GCM).
2286    \\
2287      
2288    \noindent
2289    { \underline {EVAP}  Surface Evaporation ($mm/day$) }
2290    
2291    \noindent
2292    The surface evaporation is a function of the gradient of moisture, the potential
2293    evapotranspiration fraction and the eddy exchange coefficient:
2294    \[
2295    {\bf EVAP} =  \rho \beta K_{h} (q_{surface} - q_{Nrphys})
2296    \]
2297    where $\rho$ = the atmospheric density at the surface, $\beta$ is the fraction of
2298    the potential evapotranspiration actually evaporated ($\beta=1$ over oceans), $K_{h}$ is the
2299    turbulent eddy exchange coefficient for heat and moisture at the surface in $m/sec$ and
2300    $q{surface}$ and $q_{Nrphys}$ are the specific humidity at the surface (see diagnostic
2301    number 34) and at the bottom model level, respectively.
2302    \\
2303    
2304    \noindent
2305    { \underline {DUDT} Total Zonal U-Wind Tendency  ($m/sec/day$) }
2306    
2307    \noindent
2308    {\bf DUDT} is the total time-tendency of the Zonal U-Wind due to Hydrodynamic, Diabatic,
2309    and Analysis forcing.
2310    \[
2311    {\bf DUDT} = \pp{u}{t}_{Dynamics} + \pp{u}{t}_{Moist} + \pp{u}{t}_{Turbulence} + \pp{u}{t}_{Analysis}
2312    \]
2313    \\
2314    
2315    \noindent
2316    { \underline {DVDT} Total Zonal V-Wind Tendency  ($m/sec/day$) }
2317    
2318    \noindent
2319    {\bf DVDT} is the total time-tendency of the Meridional V-Wind due to Hydrodynamic, Diabatic,
2320    and Analysis forcing.
2321    \[
2322    {\bf DVDT} = \pp{v}{t}_{Dynamics} + \pp{v}{t}_{Moist} + \pp{v}{t}_{Turbulence} + \pp{v}{t}_{Analysis}
2323    \]
2324    \\
2325    
2326    \noindent
2327    { \underline {DTDT} Total Temperature Tendency  ($deg/day$) }
2328    
2329    \noindent
2330    {\bf DTDT} is the total time-tendency of Temperature due to Hydrodynamic, Diabatic,
2331    and Analysis forcing.
2332    \begin{eqnarray*}
2333    {\bf DTDT} & = & \pp{T}{t}_{Dynamics} + \pp{T}{t}_{Moist Processes} + \pp{T}{t}_{Shortwave Radiation} \\
2334               & + & \pp{T}{t}_{Longwave Radiation} + \pp{T}{t}_{Turbulence} + \pp{T}{t}_{Analysis}
2335    \end{eqnarray*}
2336    \\
2337    
2338    \noindent
2339    { \underline {DQDT} Total Specific Humidity Tendency  ($g/kg/day$) }
2340    
2341    \noindent
2342    {\bf DQDT} is the total time-tendency of Specific Humidity due to Hydrodynamic, Diabatic,
2343    and Analysis forcing.
2344    \[
2345    {\bf DQDT} = \pp{q}{t}_{Dynamics} + \pp{q}{t}_{Moist Processes}
2346    + \pp{q}{t}_{Turbulence} + \pp{q}{t}_{Analysis}
2347    \]
2348    \\
2349      
2350    \noindent
2351    { \underline {USTAR}  Surface-Stress Velocity ($m/sec$) }
2352    
2353    \noindent
2354    The surface stress velocity, or the friction velocity, is the wind speed at
2355    the surface layer top impeded by the surface drag:
2356    \[
2357    {\bf USTAR} = C_uW_s \hspace{1cm}where: \hspace{.2cm}
2358    C_u = {k \over {\psi_m} }
2359    \]
2360    
2361    \noindent
2362    $C_u$ is the non-dimensional surface drag coefficient (see diagnostic
2363    number 10), and $W_s$ is the surface wind speed (see diagnostic number 28).
2364    
2365    \noindent
2366    { \underline {Z0}  Surface Roughness Length ($m$) }
2367    
2368    \noindent
2369    Over the land surface, the surface roughness length is interpolated to the local
2370    time from the monthly mean data of \cite{dorsell:89}. Over the ocean,
2371    the roughness length is a function of the surface-stress velocity, $u_*$.
2372    \[
2373    {\bf Z0} = c_1u^3_* + c_2u^2_* + c_3u_* + c_4 + {c_5 \over {u_*}}
2374    \]
2375    
2376    \noindent
2377    where the constants are chosen to interpolate between the reciprocal relation of
2378    \cite{kondo:75} for weak winds, and the piecewise linear relation of \cite{larpond:81}
2379    for moderate to large winds.
2380    \\
2381    
2382    \noindent
2383    { \underline {FRQTRB}  Frequency of Turbulence ($0-1$) }
2384    
2385    \noindent
2386    The fraction of time when turbulence is present is defined as the fraction of
2387    time when the turbulent kinetic energy exceeds some minimum value, defined here
2388    to be $0.005 \hspace{.1cm}m^2/sec^2$. When this criterion is met, a counter is
2389    incremented. The fraction over the averaging interval is reported.
2390    \\
2391    
2392    \noindent
2393    { \underline {PBL}  Planetary Boundary Layer Depth ($mb$) }
2394    
2395    \noindent
2396    The depth of the PBL is defined by the turbulence parameterization to be the
2397    depth at which the turbulent kinetic energy reduces to ten percent of its surface
2398    value.
2399    
2400    \[
2401    {\bf PBL} = P_{PBL} - P_{surface}
2402    \]
2403    
2404    \noindent
2405    where $P_{PBL}$ is the pressure in $mb$ at which the turbulent kinetic energy
2406    reaches one tenth of its surface value, and $P_s$ is the surface pressure.
2407    \\
2408    
2409    \noindent
2410    { \underline {SWCLR} Clear sky Heating Rate due to Shortwave Radiation ($deg/day$) }
2411    
2412    \noindent
2413    The net Shortwave heating rate is calculated as the vertical divergence of the
2414    net solar radiative fluxes.
2415    The clear-sky and cloudy-sky shortwave fluxes are calculated separately.
2416    For the clear-sky case, the shortwave fluxes and heating rates are computed with
2417    both CLMO (maximum overlap cloud fraction) and
2418    CLRO (random overlap cloud fraction) set to zero (see Section \ref{sec:fizhi:radcloud}).
2419    The shortwave routine is then called a second time, for the cloudy-sky case, with the
2420    true time-averaged cloud fractions CLMO
2421    and CLRO being used.  In all cases, a normalized incident shortwave flux is used as
2422    input at the top of the atmosphere.
2423    
2424    \noindent
2425    The heating rate due to Shortwave Radiation under clear skies is defined as:
2426    \[
2427    \pp{\rho c_p T}{t} = - {\partial \over \partial z} F(clear)_{SW}^{NET} \cdot {\rm RADSWT},
2428    \]
2429    or
2430    \[
2431    {\bf SWCLR} = \frac{g}{c_p } {\partial \over \partial p} F(clear)_{SW}^{NET}\cdot {\rm RADSWT} .
2432    \]
2433    
2434    \noindent
2435    where $g$ is the accelation due to gravity,
2436    $c_p$ is the heat capacity of air at constant pressure, RADSWT is the true incident
2437    shortwave radiation at the top of the atmosphere (See Diagnostic \#48), and
2438    \[
2439    F(clear)_{SW}^{Net} = F(clear)_{SW}^\uparrow - F(clear)_{SW}^\downarrow
2440    \]
2441    \\
2442    
2443    \noindent
2444    { \underline {OSR} Net upward Shortwave flux at the top of the model ($Watts/m^2$) }
2445    \[
2446    {\bf OSR}  =  F_{SW,top}^{NET}
2447    \]                                                                                      
2448    \noindent
2449    where top indicates the top of the first model layer used in the shortwave radiation
2450    routine.
2451    In the GCM, $p_{SW_{top}}$ = 0 mb.
2452    \\
2453    
2454    \noindent
2455    { \underline {OSRCLR} Net upward clearsky Shortwave flux at the top of the model ($Watts/m^2$) }
2456    \[
2457    {\bf OSRCLR}  =  F(clearsky)_{SW,top}^{NET}
2458    \]
2459    \noindent
2460    where top indicates the top of the first model layer used in the shortwave radiation
2461    routine.
2462    In the GCM, $p_{SW_{top}}$ = 0 mb.
2463    \\
2464    
2465    
2466    \noindent
2467    { \underline {CLDMAS} Convective Cloud Mass Flux ($kg/m^2$) }
2468    
2469    \noindent
2470    The amount of cloud mass moved per RAS timestep from all convective clouds is written:
2471    \[
2472    {\bf CLDMAS} = \eta m_B
2473    \]
2474    where $\eta$ is the entrainment, normalized by the cloud base mass flux, and $m_B$ is
2475    the cloud base mass flux. $m_B$ and $\eta$ are defined explicitly in Section \ref{sec:fizhi:mc}, the
2476    description of the convective parameterization.
2477    \\
2478    
2479    
2480    
2481    \noindent
2482    { \underline {UAVE} Time-Averaged Zonal U-Wind ($m/sec$) }
2483    
2484    \noindent
2485    The diagnostic {\bf UAVE} is simply the time-averaged Zonal U-Wind over
2486    the {\bf NUAVE} output frequency.  This is contrasted to the instantaneous
2487    Zonal U-Wind which is archived on the Prognostic Output data stream.
2488    \[
2489    {\bf UAVE} = u(\lambda, \phi, level , t)
2490    \]
2491    \\
2492    Note, {\bf UAVE} is computed and stored on the staggered C-grid.
2493    \\
2494    
2495    \noindent
2496    { \underline {VAVE} Time-Averaged Meridional V-Wind ($m/sec$) }
2497    
2498    \noindent
2499    The diagnostic {\bf VAVE} is simply the time-averaged Meridional V-Wind over
2500    the {\bf NVAVE} output frequency.  This is contrasted to the instantaneous
2501    Meridional V-Wind which is archived on the Prognostic Output data stream.
2502    \[
2503    {\bf VAVE} = v(\lambda, \phi, level , t)
2504    \]
2505    \\
2506    Note, {\bf VAVE} is computed and stored on the staggered C-grid.
2507    \\
2508    
2509    \noindent
2510    { \underline {TAVE} Time-Averaged Temperature ($Kelvin$) }
2511    
2512    \noindent
2513    The diagnostic {\bf TAVE} is simply the time-averaged Temperature over
2514    the {\bf NTAVE} output frequency.  This is contrasted to the instantaneous
2515    Temperature which is archived on the Prognostic Output data stream.
2516    \[
2517    {\bf TAVE} = T(\lambda, \phi, level , t)
2518    \]
2519    \\
2520    
2521    \noindent
2522    { \underline {QAVE} Time-Averaged Specific Humidity ($g/kg$) }
2523    
2524    \noindent
2525    The diagnostic {\bf QAVE} is simply the time-averaged Specific Humidity over
2526    the {\bf NQAVE} output frequency.  This is contrasted to the instantaneous
2527    Specific Humidity which is archived on the Prognostic Output data stream.
2528    \[
2529    {\bf QAVE} = q(\lambda, \phi, level , t)
2530    \]
2531    \\
2532    
2533    \noindent
2534    { \underline {PAVE} Time-Averaged Surface Pressure - PTOP ($mb$) }
2535    
2536    \noindent
2537    The diagnostic {\bf PAVE} is simply the time-averaged Surface Pressure - PTOP over
2538    the {\bf NPAVE} output frequency.  This is contrasted to the instantaneous
2539    Surface Pressure - PTOP which is archived on the Prognostic Output data stream.
2540    \begin{eqnarray*}
2541    {\bf PAVE} & =  & \pi(\lambda, \phi, level , t) \\
2542               & =  & p_s(\lambda, \phi, level , t) - p_T
2543    \end{eqnarray*}
2544    \\
2545    
2546    
2547    \noindent
2548    { \underline {QQAVE} Time-Averaged Turbulent Kinetic Energy $(m/sec)^2$ }
2549    
2550    \noindent
2551    The diagnostic {\bf QQAVE} is simply the time-averaged prognostic Turbulent Kinetic Energy
2552    produced by the GCM Turbulence parameterization over
2553    the {\bf NQQAVE} output frequency.  This is contrasted to the instantaneous
2554    Turbulent Kinetic Energy which is archived on the Prognostic Output data stream.
2555    \[
2556    {\bf QQAVE} = qq(\lambda, \phi, level , t)
2557    \]
2558    \\
2559    Note, {\bf QQAVE} is computed and stored at the ``mass-point'' locations on the staggered C-grid.
2560    \\
2561    
2562    \noindent
2563    { \underline {SWGCLR} Net downward clearsky Shortwave flux at the surface ($Watts/m^2$) }
2564    
2565    \noindent
2566    \begin{eqnarray*}
2567    {\bf SWGCLR} & =  & F(clearsky)_{SW,Nrphys+1}^{Net} \\
2568                 & =  & F(clearsky)_{SW,Nrphys+1}^\downarrow - F(clearsky)_{SW,Nrphys+1}^\uparrow
2569    \end{eqnarray*}
2570    \noindent
2571    \\
2572    where Nrphys+1 indicates the lowest model edge-level, or $p = p_{surf}$.
2573    $F(clearsky){SW}^\downarrow$ is
2574    the downward clearsky Shortwave flux and $F(clearsky)_{SW}^\uparrow$ is
2575    the upward clearsky Shortwave flux.
2576    \\
2577    
2578    \noindent
2579    { \underline {DIABU} Total Diabatic Zonal U-Wind Tendency  ($m/sec/day$) }
2580    
2581    \noindent
2582    {\bf DIABU} is the total time-tendency of the Zonal U-Wind due to Diabatic processes
2583    and the Analysis forcing.
2584    \[
2585    {\bf DIABU} = \pp{u}{t}_{Moist} + \pp{u}{t}_{Turbulence} + \pp{u}{t}_{Analysis}
2586    \]
2587    \\
2588    
2589    \noindent
2590    { \underline {DIABV} Total Diabatic Meridional V-Wind Tendency  ($m/sec/day$) }
2591    
2592    \noindent
2593    {\bf DIABV} is the total time-tendency of the Meridional V-Wind due to Diabatic processes
2594    and the Analysis forcing.
2595    \[
2596    {\bf DIABV} = \pp{v}{t}_{Moist} + \pp{v}{t}_{Turbulence} + \pp{v}{t}_{Analysis}
2597    \]
2598    \\
2599    
2600    \noindent
2601    { \underline {DIABT} Total Diabatic Temperature Tendency  ($deg/day$) }
2602    
2603    \noindent
2604    {\bf DIABT} is the total time-tendency of Temperature due to Diabatic processes
2605    and the Analysis forcing.
2606    \begin{eqnarray*}
2607    {\bf DIABT} & = & \pp{T}{t}_{Moist Processes} + \pp{T}{t}_{Shortwave Radiation} \\
2608               & + & \pp{T}{t}_{Longwave Radiation} + \pp{T}{t}_{Turbulence} + \pp{T}{t}_{Analysis}
2609    \end{eqnarray*}
2610    \\
2611    If we define the time-tendency of Temperature due to Diabatic processes as
2612    \begin{eqnarray*}
2613    \pp{T}{t}_{Diabatic} & = & \pp{T}{t}_{Moist Processes} + \pp{T}{t}_{Shortwave Radiation} \\
2614                         & + & \pp{T}{t}_{Longwave Radiation} + \pp{T}{t}_{Turbulence}
2615    \end{eqnarray*}
2616    then, since there are no surface pressure changes due to Diabatic processes, we may write
2617    \[
2618    \pp{T}{t}_{Diabatic} = {p^\kappa \over \pi }\pp{\pi \theta}{t}_{Diabatic}
2619    \]
2620    where $\theta = T/p^\kappa$.  Thus, {\bf DIABT} may be written as
2621    \[
2622    {\bf DIABT} = {p^\kappa \over \pi } \left( \pp{\pi \theta}{t}_{Diabatic} + \pp{\pi \theta}{t}_{Analysis} \right)
2623    \]
2624    \\
2625    
2626    \noindent
2627    { \underline {DIABQ} Total Diabatic Specific Humidity Tendency  ($g/kg/day$) }
2628    
2629    \noindent
2630    {\bf DIABQ} is the total time-tendency of Specific Humidity due to Diabatic processes
2631    and the Analysis forcing.
2632    \[
2633    {\bf DIABQ} = \pp{q}{t}_{Moist Processes} + \pp{q}{t}_{Turbulence} + \pp{q}{t}_{Analysis}
2634    \]
2635    If we define the time-tendency of Specific Humidity due to Diabatic processes as
2636    \[
2637    \pp{q}{t}_{Diabatic} = \pp{q}{t}_{Moist Processes} + \pp{q}{t}_{Turbulence}
2638    \]
2639    then, since there are no surface pressure changes due to Diabatic processes, we may write
2640    \[
2641    \pp{q}{t}_{Diabatic} = {1 \over \pi }\pp{\pi q}{t}_{Diabatic}
2642    \]
2643    Thus, {\bf DIABQ} may be written as
2644    \[
2645    {\bf DIABQ} = {1 \over \pi } \left( \pp{\pi q}{t}_{Diabatic} + \pp{\pi q}{t}_{Analysis} \right)
2646    \]
2647    \\
2648    
2649    \noindent
2650    { \underline {VINTUQ} Vertically Integrated Moisture Flux ($m/sec \cdot g/kg$) }
2651    
2652    \noindent
2653    The vertically integrated moisture flux due to the zonal u-wind is obtained by integrating
2654    $u q$ over the depth of the atmosphere at each model timestep,
2655    and dividing by the total mass of the column.
2656    \[
2657    {\bf VINTUQ} = \frac{ \int_{surf}^{top} u q \rho dz  } { \int_{surf}^{top} \rho dz  }
2658    \]
2659    Using $\rho \delta z = -{\delta p \over g} = - {1 \over g} \delta p$, we have
2660    \[
2661    {\bf VINTUQ} = { \int_0^1 u q dp  }
2662    \]
2663    \\
2664    
2665    
2666    \noindent
2667    { \underline {VINTVQ} Vertically Integrated Moisture Flux ($m/sec \cdot g/kg$) }
2668    
2669    \noindent
2670    The vertically integrated moisture flux due to the meridional v-wind is obtained by integrating
2671    $v q$ over the depth of the atmosphere at each model timestep,
2672    and dividing by the total mass of the column.
2673    \[
2674    {\bf VINTVQ} = \frac{ \int_{surf}^{top} v q \rho dz  } { \int_{surf}^{top} \rho dz  }
2675    \]
2676    Using $\rho \delta z = -{\delta p \over g} = - {1 \over g} \delta p$, we have
2677    \[
2678    {\bf VINTVQ} = { \int_0^1 v q dp  }
2679    \]
2680    \\
2681    
2682    
2683    \noindent
2684    { \underline {VINTUT} Vertically Integrated Heat Flux ($m/sec \cdot deg$) }
2685    
2686    \noindent
2687    The vertically integrated heat flux due to the zonal u-wind is obtained by integrating
2688    $u T$ over the depth of the atmosphere at each model timestep,
2689    and dividing by the total mass of the column.
2690    \[
2691    {\bf VINTUT} = \frac{ \int_{surf}^{top} u T \rho dz  } { \int_{surf}^{top} \rho dz  }
2692    \]
2693    Or,
2694    \[
2695    {\bf VINTUT} = { \int_0^1 u T dp  }
2696    \]
2697    \\
2698    
2699    \noindent
2700    { \underline {VINTVT} Vertically Integrated Heat Flux ($m/sec \cdot deg$) }
2701    
2702    \noindent
2703    The vertically integrated heat flux due to the meridional v-wind is obtained by integrating
2704    $v T$ over the depth of the atmosphere at each model timestep,
2705    and dividing by the total mass of the column.
2706    \[
2707    {\bf VINTVT} = \frac{ \int_{surf}^{top} v T \rho dz  } { \int_{surf}^{top} \rho dz  }
2708    \]
2709    Using $\rho \delta z = -{\delta p \over g} $, we have
2710    \[
2711    {\bf VINTVT} = { \int_0^1 v T dp  }
2712    \]
2713    \\
2714    
2715    \noindent
2716    { \underline {CLDFRC} Total 2-Dimensional Cloud Fracton ($0-1$) }
2717    
2718    If we define the
2719    time-averaged random and maximum overlapped cloudiness as CLRO and
2720    CLMO respectively, then the probability of clear sky associated
2721    with random overlapped clouds at any level is (1-CLRO) while the probability of
2722    clear sky associated with maximum overlapped clouds at any level is (1-CLMO).
2723    The total clear sky probability is given by (1-CLRO)*(1-CLMO), thus
2724    the total cloud fraction at each  level may be obtained by
2725    1-(1-CLRO)*(1-CLMO).
2726    
2727    At any given level, we may define the clear line-of-site probability by
2728    appropriately accounting for the maximum and random overlap
2729    cloudiness.  The clear line-of-site probability is defined to be
2730    equal to the product of the clear line-of-site probabilities
2731    associated with random and maximum overlap cloudiness.  The clear
2732    line-of-site probability $C(p,p^{\prime})$ associated with maximum overlap clouds,
2733    from the current pressure $p$
2734    to the model top pressure, $p^{\prime} = p_{top}$, or the model surface pressure, $p^{\prime} = p_{surf}$,
2735    is simply 1.0 minus the largest maximum overlap cloud value along  the
2736    line-of-site, ie.
2737    
2738    $$1-MAX_p^{p^{\prime}} \left( CLMO_p \right)$$
2739    
2740    Thus, even in the time-averaged sense it is assumed that the
2741    maximum overlap clouds are correlated in the vertical.  The clear
2742    line-of-site probability associated with random overlap clouds is
2743    defined to be the product of the clear sky probabilities at each
2744    level along the line-of-site, ie.
2745    
2746    $$\prod_{p}^{p^{\prime}} \left( 1-CLRO_p \right)$$
2747    
2748    The total cloud fraction at a given level associated with a line-
2749    of-site calculation is given by
2750    
2751    $$1-\left( 1-MAX_p^{p^{\prime}} \left[ CLMO_p \right] \right)
2752        \prod_p^{p^{\prime}} \left( 1-CLRO_p \right)$$
2753    
2754    
2755    \noindent
2756    The 2-dimensional net cloud fraction as seen from the top of the
2757    atmosphere is given by
2758    \[
2759    {\bf CLDFRC} = 1-\left( 1-MAX_{l=l_1}^{Nrphys} \left[ CLMO_l \right] \right)
2760        \prod_{l=l_1}^{Nrphys} \left( 1-CLRO_l \right)
2761    \]
2762    \\
2763    For a complete description of cloud/radiative interactions, see Section \ref{sec:fizhi:radcloud}.
2764    
2765    
2766    \noindent
2767    { \underline {QINT} Total Precipitable Water ($gm/cm^2$) }
2768    
2769    \noindent
2770    The Total Precipitable Water is defined as the vertical integral of the specific humidity,
2771    given by:
2772    \begin{eqnarray*}
2773    {\bf QINT} & = & \int_{surf}^{top} \rho q dz \\
2774               & = & {\pi \over g} \int_0^1 q dp
2775    \end{eqnarray*}
2776    where we have used the hydrostatic relation
2777    $\rho \delta z = -{\delta p \over g} $.
2778    \\
2779    
2780    
2781    \noindent
2782    { \underline {U2M}  Zonal U-Wind at 2 Meter Depth ($m/sec$) }
2783    
2784    \noindent
2785    The u-wind at the 2-meter depth is determined from the similarity theory:
2786    \[
2787    {\bf U2M} = {u_* \over k} \psi_{m_{2m}} {u_{sl} \over {W_s}} =
2788    { \psi_{m_{2m}} \over {\psi_{m_{sl}} }}u_{sl}
2789    \]
2790    
2791    \noindent
2792    where $\psi_m(2m)$ is the non-dimensional wind shear at two meters, and the subscript
2793    $sl$ refers to the height of the top of the surface layer. If the roughness height
2794    is above two meters, ${\bf U2M}$ is undefined.
2795    \\
2796    
2797    \noindent
2798    { \underline {V2M}  Meridional V-Wind at 2 Meter Depth ($m/sec$) }
2799    
2800    \noindent
2801    The v-wind at the 2-meter depth is a determined from the similarity theory:
2802    \[
2803    {\bf V2M} = {u_* \over k} \psi_{m_{2m}} {v_{sl} \over {W_s}} =
2804    { \psi_{m_{2m}} \over {\psi_{m_{sl}} }}v_{sl}
2805    \]
2806    
2807    \noindent
2808    where $\psi_m(2m)$ is the non-dimensional wind shear at two meters, and the subscript
2809    $sl$ refers to the height of the top of the surface layer. If the roughness height
2810    is above two meters, ${\bf V2M}$ is undefined.
2811    \\
2812    
2813    \noindent
2814    { \underline {T2M}  Temperature at 2 Meter Depth ($deg \hspace{.1cm} K$) }
2815    
2816    \noindent
2817    The temperature at the 2-meter depth is a determined from the similarity theory:
2818    \[
2819    {\bf T2M} = P^{\kappa} ({\theta* \over k} ({\psi_{h_{2m}}+\psi_g}) + \theta_{surf} ) =
2820    P^{\kappa}(\theta_{surf} + { {\psi_{h_{2m}}+\psi_g} \over {{\psi_{h_{sl}}+\psi_g}} }
2821    (\theta_{sl} - \theta_{surf}))
2822    \]
2823    where:
2824    \[
2825    \theta_* = - { (\overline{w^{\prime}\theta^{\prime}}) \over {u_*} }
2826    \]
2827    
2828    \noindent
2829    where $\psi_h(2m)$ is the non-dimensional temperature gradient at two meters, $\psi_g$ is
2830    the non-dimensional temperature gradient in the viscous sublayer, and the subscript
2831    $sl$ refers to the height of the top of the surface layer. If the roughness height
2832    is above two meters, ${\bf T2M}$ is undefined.
2833    \\
2834    
2835    \noindent
2836    { \underline {Q2M}  Specific Humidity at 2 Meter Depth ($g/kg$) }
2837    
2838    \noindent
2839    The specific humidity at the 2-meter depth is determined from the similarity theory:
2840    \[
2841    {\bf Q2M} = P^{\kappa} ({q_* \over k} ({\psi_{h_{2m}}+\psi_g}) + q_{surf} ) =
2842    P^{\kappa}(q_{surf} + { {\psi_{h_{2m}}+\psi_g} \over {{\psi_{h_{sl}}+\psi_g}} }
2843    (q_{sl} - q_{surf}))
2844    \]
2845    where:
2846    \[
2847    q_* = - { (\overline{w^{\prime}q^{\prime}}) \over {u_*} }
2848    \]
2849    
2850    \noindent
2851    where $\psi_h(2m)$ is the non-dimensional temperature gradient at two meters, $\psi_g$ is
2852    the non-dimensional temperature gradient in the viscous sublayer, and the subscript
2853    $sl$ refers to the height of the top of the surface layer. If the roughness height
2854    is above two meters, ${\bf Q2M}$ is undefined.
2855    \\
2856    
2857    \noindent
2858    { \underline {U10M}  Zonal U-Wind at 10 Meter Depth ($m/sec$) }
2859    
2860    \noindent
2861    The u-wind at the 10-meter depth is an interpolation between the surface wind
2862    and the model lowest level wind using the ratio of the non-dimensional wind shear
2863    at the two levels:
2864    \[
2865    {\bf U10M} = {u_* \over k} \psi_{m_{10m}} {u_{sl} \over {W_s}} =
2866    { \psi_{m_{10m}} \over {\psi_{m_{sl}} }}u_{sl}
2867    \]
2868    
2869    \noindent
2870    where $\psi_m(10m)$ is the non-dimensional wind shear at ten meters, and the subscript
2871    $sl$ refers to the height of the top of the surface layer.
2872    \\
2873    
2874    \noindent
2875    { \underline {V10M}  Meridional V-Wind at 10 Meter Depth ($m/sec$) }
2876    
2877    \noindent
2878    The v-wind at the 10-meter depth is an interpolation between the surface wind
2879    and the model lowest level wind using the ratio of the non-dimensional wind shear
2880    at the two levels:
2881    \[
2882    {\bf V10M} = {u_* \over k} \psi_{m_{10m}} {v_{sl} \over {W_s}} =
2883    { \psi_{m_{10m}} \over {\psi_{m_{sl}} }}v_{sl}
2884    \]
2885    
2886    \noindent
2887    where $\psi_m(10m)$ is the non-dimensional wind shear at ten meters, and the subscript
2888    $sl$ refers to the height of the top of the surface layer.
2889    \\
2890    
2891    \noindent
2892    { \underline {T10M}  Temperature at 10 Meter Depth ($deg \hspace{.1cm} K$) }
2893    
2894    \noindent
2895    The temperature at the 10-meter depth is an interpolation between the surface potential
2896    temperature and the model lowest level potential temperature using the ratio of the
2897    non-dimensional temperature gradient at the two levels:
2898    \[
2899    {\bf T10M} = P^{\kappa} ({\theta* \over k} ({\psi_{h_{10m}}+\psi_g}) + \theta_{surf} ) =
2900    P^{\kappa}(\theta_{surf} + { {\psi_{h_{10m}}+\psi_g} \over {{\psi_{h_{sl}}+\psi_g}} }
2901    (\theta_{sl} - \theta_{surf}))
2902    \]
2903    where:
2904    \[
2905    \theta_* = - { (\overline{w^{\prime}\theta^{\prime}}) \over {u_*} }
2906    \]
2907    
2908    \noindent
2909    where $\psi_h(10m)$ is the non-dimensional temperature gradient at two meters, $\psi_g$ is
2910    the non-dimensional temperature gradient in the viscous sublayer, and the subscript
2911    $sl$ refers to the height of the top of the surface layer.
2912    \\
2913    
2914    \noindent
2915    { \underline {Q10M}  Specific Humidity at 10 Meter Depth ($g/kg$) }
2916    
2917    \noindent
2918    The specific humidity at the 10-meter depth is an interpolation between the surface specific
2919    humidity and the model lowest level specific humidity using the ratio of the
2920    non-dimensional temperature gradient at the two levels:
2921    \[
2922    {\bf Q10M} = P^{\kappa} ({q_* \over k} ({\psi_{h_{10m}}+\psi_g}) + q_{surf} ) =
2923    P^{\kappa}(q_{surf} + { {\psi_{h_{10m}}+\psi_g} \over {{\psi_{h_{sl}}+\psi_g}} }
2924    (q_{sl} - q_{surf}))
2925    \]
2926    where:
2927    \[
2928    q_* =  - { (\overline{w^{\prime}q^{\prime}}) \over {u_*} }
2929    \]
2930    
2931    \noindent
2932    where $\psi_h(10m)$ is the non-dimensional temperature gradient at two meters, $\psi_g$ is
2933    the non-dimensional temperature gradient in the viscous sublayer, and the subscript
2934    $sl$ refers to the height of the top of the surface layer.
2935    \\
2936    
2937    \noindent
2938    { \underline {DTRAIN} Cloud Detrainment Mass Flux ($kg/m^2$) }
2939    
2940    The amount of cloud mass moved per RAS timestep at the cloud detrainment level is written:
2941    \[
2942    {\bf DTRAIN} = \eta_{r_D}m_B
2943    \]
2944    \noindent
2945    where $r_D$ is the detrainment level,
2946    $m_B$ is the cloud base mass flux, and $\eta$
2947    is the entrainment, defined in Section \ref{sec:fizhi:mc}.
2948    \\
2949    
2950    \noindent
2951    { \underline {QFILL}  Filling of negative Specific Humidity ($g/kg/day$) }
2952    
2953    \noindent
2954    Due to computational errors associated with the numerical scheme used for
2955    the advection of moisture, negative values of specific humidity may be generated.  The
2956    specific humidity is checked for negative values after every dynamics timestep.  If negative
2957    values have been produced, a filling algorithm is invoked which redistributes moisture from
2958    below.  Diagnostic {\bf QFILL} is equal to the net filling needed
2959    to eliminate negative specific humidity, scaled to a per-day rate:
2960    \[
2961    {\bf QFILL} = q^{n+1}_{final} - q^{n+1}_{initial}
2962    \]
2963    where
2964    \[
2965    q^{n+1} = (\pi q)^{n+1} / \pi^{n+1}
2966    \]
2967    
2968    
2969    \subsubsection{Key subroutines, parameters and files}
2970    
2971    \subsubsection{Dos and donts}
2972    
2973    \subsubsection{Fizhi Reference}
2974    
2975    \subsubsection{Experiments and tutorials that use fizhi}
2976    \label{sec:pkg:fizhi:experiments}
2977    
2978    \begin{itemize}
2979    \item{Global atmosphere experiment with realistic SST and topography in fizhi-cs-32x32x10 verification directory. }
2980    \item{Global atmosphere aqua planet experiment in fizhi-cs-aqualev20 verification directory. }
2981    \end{itemize}
2982    

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