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revision 1.7 by edhill, Tue Oct 12 18:16:03 2004 UTC revision 1.12 by molod, Tue Aug 2 21:17:38 2005 UTC
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1  \section{Fizhi: High-end Atmospheric Physics}  \subsection{Fizhi: High-end Atmospheric Physics}
2  \label{sec:pkg:fizhi}  \label{sec:pkg:fizhi}
3  \begin{rawhtml}  \begin{rawhtml}
4  <!-- CMIREDIR:package_fizhi: -->  <!-- CMIREDIR:package_fizhi: -->
5  \end{rawhtml}  \end{rawhtml}
6  \input{texinputs/epsf.tex}  \input{texinputs/epsf.tex}
7    
8  \subsection{Introduction}  \subsubsection{Introduction}
9  The fizhi (high-end atmospheric physics) package includes a collection of state-of-the-art  The fizhi (high-end atmospheric physics) package includes a collection of state-of-the-art
10  physical parameterizations for atmospheric radiation, cumulus convection, atmospheric  physical parameterizations for atmospheric radiation, cumulus convection, atmospheric
11  boundary layer turbulence, and land surface processes.  boundary layer turbulence, and land surface processes. The collection of atmospheric
12    physics parameterizations were originally used together as part of the GEOS-3
13    (Goddard Earth Observing System-3) GCM developed at the NASA/Goddard Global Modelling
14    and Assimilation Office (GMAO).
15    
16  % *************************************************************************  % *************************************************************************
17  % *************************************************************************  % *************************************************************************
18    
19  \subsection{Equations}  \subsubsection{Equations}
20    
21  \subsubsection{Moist Convective Processes}  Moist Convective Processes:
22    
23  \paragraph{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 43  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 101  $\alpha$ 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 186  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 221  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  \paragraph{Shortwave Radiation}  \paragraph{Shortwave Radiation}
# Line 231  heating due to the absoption by water va Line 234  heating due to the absoption by water va
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 321  low/middle/high classification, and appr Line 324  low/middle/high classification, and appr
324    
325  \paragraph{Longwave Radiation}  \paragraph{Longwave Radiation}
326    
327  The longwave radiation package used in the fizhi package is thoroughly described by Chou and Suarez (1994).  The longwave radiation package used in the fizhi package is thoroughly described by \cite{chsz:94}.
328  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
329  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,
330  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 357  Band & Spectral Range (cm$^{-1}$) & Abso Line 360  Band & Spectral Range (cm$^{-1}$) & Abso
360  \end{tabular}  \end{tabular}
361  \end{center}  \end{center}
362  \vspace{0.1in}  \vspace{0.1in}
363  \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})}
364  \label{tab:fizhi:longwave}  \label{tab:fizhi:longwave}
365  \end{table}  \end{table}
366    
# Line 428  The cloud fraction values are time-avera Line 431  The cloud fraction values are time-avera
431  hours).  Therefore, in a time-averaged sense, both convective and large-scale  hours).  Therefore, in a time-averaged sense, both convective and large-scale
432  cloudiness can exist in a given grid-box.    cloudiness can exist in a given grid-box.  
433    
434  \subsubsection{Turbulence}  \paragraph{Turbulence}:
435    
436  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
437  vertical exchange of heat, moisture, and momentum.    vertical exchange of heat, moisture, and momentum.  
438  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 458  Within the atmosphere, the time evolutio Line 462  Within the atmosphere, the time evolutio
462  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
463  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.
464  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
465  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
466  kinetic energy (TKE),  kinetic energy (TKE),
467    
468  \[ {\h}{q^2}={\overline{{u^{\prime}}^2}}+{\overline{{v^{\prime}}^2}}+{\overline{{w^{\prime}}^2}}, \]  \[ {\h}{q^2}={\overline{{u^{\prime}}^2}}+{\overline{{v^{\prime}}^2}}+{\overline{{w^{\prime}}^2}}, \]
# Line 492  of TKE. Line 496  of TKE.
496    
497  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
498  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
499  $K_m$, 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
500  and Labraga (1988), these diffusion coefficients are expressed as  \cite{helflab:88}, these diffusion coefficients are expressed as
501    
502  \[  \[
503  K_h  K_h
# Line 568  where $\psi_h$ is the surface layer non- Line 572  where $\psi_h$ is the surface layer non-
572  \]  \]
573  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
574  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
575  layers according to Helfand and Schubert, 1995.  layers according to \cite{helfschu:95}.
576    
577  $\psi_g$ 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,
578  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
579  elements, in which temperature and moisture gradients can be quite large.  elements, in which temperature and moisture gradients can be quite large.
580  Based on Yaglom and Kader (1974):  Based on \cite{yagkad:74}:
581  \[  \[
582  \psi_{g} = { 0.55 (Pr^{2/3} - 0.2) \over \nu^{1/2} }  \psi_{g} = { 0.55 (Pr^{2/3} - 0.2) \over \nu^{1/2} }
583  (h_{0}u_{*} - h_{0_{ref}}u_{*_{ref}})^{1/2}  (h_{0}u_{*} - h_{0_{ref}}u_{*_{ref}})^{1/2}
# Line 587  The surface roughness length over oceans Line 591  The surface roughness length over oceans
591  {z_0} = c_1u^3_* + c_2u^2_* + c_3u_* + c_4 + {c_5 \over {u_*}}  {z_0} = c_1u^3_* + c_2u^2_* + c_3u_* + c_4 + {c_5 \over {u_*}}
592  \]  \]
593  where the constants are chosen to interpolate between the reciprocal relation of  where the constants are chosen to interpolate between the reciprocal relation of
594  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}
595  for moderate to large winds.  Roughness lengths over land are specified  for moderate to large winds.  Roughness lengths over land are specified
596  from the climatology of Dorman and Sellers (1989).  from the climatology of \cite{dorsell:89}.
597    
598  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
599  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
600  (Panofsky, 1973) for momentum, and its generalization for heat and moisture:    (\cite{pano:73}) for momentum, and its generalization for heat and moisture:  
601  \[  \[
602  {\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}
603  {\phi_h}^2 - 18 \zeta {\phi_h}^3 = 1 \hspace{1cm} .  {\phi_h}^2 - 18 \zeta {\phi_h}^3 = 1 \hspace{1cm} .
# Line 602  The function for heat and moisture assur Line 606  The function for heat and moisture assur
606  speed approaches zero.  speed approaches zero.
607    
608  For a stable surface layer, the stability functions are the observationally  For a stable surface layer, the stability functions are the observationally
609  based functions of Clarke (1970),  slightly modified for  based functions of \cite{clarke:70},  slightly modified for
610  the momemtum flux:    the momemtum flux:  
611  \[  \[
612  {\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 660  be $3 \hspace{.1cm} m$ where sea ice is Line 664  be $3 \hspace{.1cm} m$ where sea ice is
664  surface temperature of the ice.  surface temperature of the ice.
665    
666  $C_g$ 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
667  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:
668  \[  \[
669  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}
670  {86400 \over 2 \pi} } \, \, .  {86400 \over 2 \pi} } \, \, .
# Line 672  by $2 \pi$ $radians/ Line 676  by $2 \pi$ $radians/
676  day$, 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,
677  is a function of the ground wetness, $W$.  is a function of the ground wetness, $W$.
678    
679  \subsubsection{Land Surface Processes}  Land Surface Processes:
680    
681  \paragraph{Surface Type}  \paragraph{Surface Type}
682  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})
683  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
684  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
685  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
686  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
687  Defries and Townshend (1994), and information about the location of permanent  \cite{deftow:94}, and information about the location of permanent
688  ice was obtained from the classifications of Dorman and Sellers (1989).  ice was obtained from the classifications of \cite{dorsell:89}.
689  The surface type for the \txt GCM grid is shown in Figure \ref{fig:fizhi:surftype}.  The surface type for the \txt GCM grid is shown in Figure \ref{fig:fizhi:surftype}.
690  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
691  10 minute by 10 minute Navy topography  10 minute by 10 minute Navy topography
# Line 735  and surface albedo.} Line 739  and surface albedo.}
739    
740  \paragraph{Surface Roughness}  \paragraph{Surface Roughness}
741  The surface roughness length over oceans is computed iteratively with the wind  The surface roughness length over oceans is computed iteratively with the wind
742  stress by the surface layer parameterization (Helfand and Schubert, 1991).  stress by the surface layer parameterization (\cite{helfschu:95}).
743  It employs an interpolation between the functions of Large and Pond (1981)  It employs an interpolation between the functions of \cite{larpond:81}
744  for high winds and of Kondo (1975) for weak winds.  for high winds and of \cite{kondo:75} for weak winds.
745    
746    
747  \paragraph{Albedo}  \paragraph{Albedo}
748  The surface albedo computation, described in Koster and Suarez (1991),  The surface albedo computation, described in \cite{ks:91},
749  employs the ``two stream'' approximation used in Sellers' (1987) Simple Biosphere (SiB)  employs the ``two stream'' approximation used in Sellers' (1987) Simple Biosphere (SiB)
750  Model which distinguishes between the direct and diffuse albedos in the visible  Model which distinguishes between the direct and diffuse albedos in the visible
751  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 750  sun), the greenness fraction, the vegeta Line 754  sun), the greenness fraction, the vegeta
754  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
755  to the height of the vegetation elements.  to the height of the vegetation elements.
756    
757  \subsubsection{Gravity Wave Drag}  \paragraph{Gravity Wave Drag}:
758  The fizhi package employs the gravity wave drag scheme of Zhou et al. (1996).  
759    The fizhi package employs the gravity wave drag scheme of \cite{zhouetal:95}).
760  This scheme is a modified version of Vernekar et al. (1992),  This scheme is a modified version of Vernekar et al. (1992),
761  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).  
762  In this version, the gravity wave stress at the surface is  In this version, the gravity wave stress at the surface is
# Line 768  A modification introduced by Zhou et al. Line 773  A modification introduced by Zhou et al.
773  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.  
774  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.
775    
776  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}.
777  Experiments using the gravity wave drag parameterization yielded significant and  Experiments using the gravity wave drag parameterization yielded significant and
778  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
779  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 784  of mountain torque (through a redistribu Line 789  of mountain torque (through a redistribu
789  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).  
790    
791    
792  \subsubsection{Boundary Conditions and other Input Data}  Boundary Conditions and other Input Data:
793    
794  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
795  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 825  current years and frequencies available. Line 830  current years and frequencies available.
830  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
831  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
832  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
833  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.  
834    
835  \begin{figure*}[htbp]  The standard deviation of the subgrid-scale topography is computed by interpolating the 10 minute
836    \centerline{  \epsfysize=7.0in  \epsfbox{part6/lanczos.ps}}  data to the model's resolution and re-interpolating back to the 10 minute by 10 minute resolution.
   \caption{ \label{fig:fizhi:lanczos} Comparison between the Lanczos and $mth$-order Shapiro filter  
   response functions for $m$ = 2, 4, and 8. }  
 \end{figure*}  
   
 The standard deviation of the subgrid-scale topography  
 is computed from a modified version of the the Navy 10 minute by 10 minute dataset.  
 The 10 minute by 10 minute topography is passed through a wavelet  
 filter in both dimensions which removes the scale smaller than 20 minutes.  
 The topography is then averaged to $1^\circ x 1^\circ$ grid resolution, and then  
 re-interpolated back to the 10 minute by 10 minute resolution.  
837  The sub-grid scale variance is constructed based on this smoothed dataset.  The sub-grid scale variance is constructed based on this smoothed dataset.
838    
839    
# Line 892  model's grid location and current time, Line 845  model's grid location and current time,
845  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,
846  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.
847    
 \subsection{Key subroutines, parameters and files}  
848    
849  \subsection{Dos and donts}  \subsubsection{Fizhi Diagnostics}
850    
851    Fizhi Diagnostic Menu:
852    \label{sec:fizhi-diagnostics:menu}
853    
854    \begin{tabular}{llll}
855    \hline\hline
856     NAME & UNITS & LEVELS & DESCRIPTION \\
857    \hline
858    
859    &\\
860     UFLUX    &   $Newton/m^2$  &    1  
861             &\begin{minipage}[t]{3in}
862              {Surface U-Wind Stress on the atmosphere}
863             \end{minipage}\\
864     VFLUX    &   $Newton/m^2$  &    1  
865             &\begin{minipage}[t]{3in}
866              {Surface V-Wind Stress on the atmosphere}
867             \end{minipage}\\
868     HFLUX    &   $Watts/m^2$  &    1  
869             &\begin{minipage}[t]{3in}
870              {Surface Flux of Sensible Heat}
871             \end{minipage}\\
872     EFLUX    &   $Watts/m^2$  &    1  
873             &\begin{minipage}[t]{3in}
874              {Surface Flux of Latent Heat}
875             \end{minipage}\\
876     QICE     &   $Watts/m^2$  &    1  
877             &\begin{minipage}[t]{3in}
878              {Heat Conduction through Sea-Ice}
879             \end{minipage}\\
880     RADLWG   &   $Watts/m^2$ &    1  
881             &\begin{minipage}[t]{3in}
882              {Net upward LW flux at the ground}
883             \end{minipage}\\
884     RADSWG   &   $Watts/m^2$  &    1
885             &\begin{minipage}[t]{3in}
886              {Net downward SW flux at the ground}
887             \end{minipage}\\
888     RI       &  $dimensionless$ &  Nrphys
889             &\begin{minipage}[t]{3in}
890              {Richardson Number}
891             \end{minipage}\\
892     CT       &  $dimensionless$ &  1
893             &\begin{minipage}[t]{3in}
894              {Surface Drag coefficient for T and Q}
895             \end{minipage}\\
896     CU       & $dimensionless$ &  1
897         &\begin{minipage}[t]{3in}
898          {Surface Drag coefficient for U and V}
899         \end{minipage}\\
900     ET       &  $m^2/sec$ &  Nrphys
901         &\begin{minipage}[t]{3in}
902          {Diffusivity coefficient for T and Q}
903         \end{minipage}\\
904     EU       &  $m^2/sec$ &  Nrphys
905         &\begin{minipage}[t]{3in}
906          {Diffusivity coefficient for U and V}
907         \end{minipage}\\
908     TURBU    &  $m/sec/day$ &  Nrphys
909         &\begin{minipage}[t]{3in}
910          {U-Momentum Changes due to Turbulence}
911         \end{minipage}\\
912     TURBV    &  $m/sec/day$ &  Nrphys
913         &\begin{minipage}[t]{3in}
914          {V-Momentum Changes due to Turbulence}
915         \end{minipage}\\
916     TURBT    &  $deg/day$ &  Nrphys
917         &\begin{minipage}[t]{3in}
918          {Temperature Changes due to Turbulence}
919         \end{minipage}\\
920     TURBQ    &  $g/kg/day$ &  Nrphys
921         &\begin{minipage}[t]{3in}
922          {Specific Humidity Changes due to Turbulence}
923         \end{minipage}\\
924     MOISTT   &   $deg/day$ &  Nrphys
925         &\begin{minipage}[t]{3in}
926          {Temperature Changes due to Moist Processes}
927         \end{minipage}\\
928     MOISTQ   &  $g/kg/day$ &  Nrphys
929         &\begin{minipage}[t]{3in}
930          {Specific Humidity Changes due to Moist Processes}
931         \end{minipage}\\
932     RADLW    &  $deg/day$ &  Nrphys
933         &\begin{minipage}[t]{3in}
934          {Net Longwave heating rate for each level}
935         \end{minipage}\\
936     RADSW    &  $deg/day$ &  Nrphys
937         &\begin{minipage}[t]{3in}
938          {Net Shortwave heating rate for each level}
939         \end{minipage}\\
940     PREACC   &  $mm/day$ &  1
941         &\begin{minipage}[t]{3in}
942          {Total Precipitation}
943         \end{minipage}\\
944     PRECON   &  $mm/day$ &  1
945         &\begin{minipage}[t]{3in}
946          {Convective Precipitation}
947         \end{minipage}\\
948     TUFLUX   &  $Newton/m^2$ &  Nrphys
949         &\begin{minipage}[t]{3in}
950          {Turbulent Flux of U-Momentum}
951         \end{minipage}\\
952     TVFLUX   &  $Newton/m^2$ &  Nrphys
953         &\begin{minipage}[t]{3in}
954          {Turbulent Flux of V-Momentum}
955         \end{minipage}\\
956     TTFLUX   &  $Watts/m^2$ &  Nrphys
957         &\begin{minipage}[t]{3in}
958          {Turbulent Flux of Sensible Heat}
959         \end{minipage}\\
960    \end{tabular}
961    
962    \newpage
963    \vspace*{\fill}
964    \begin{tabular}{llll}
965    \hline\hline
966     NAME & UNITS & LEVELS & DESCRIPTION \\
967    \hline
968    
969    &\\
970     TQFLUX   &  $Watts/m^2$ &  Nrphys
971         &\begin{minipage}[t]{3in}
972          {Turbulent Flux of Latent Heat}
973         \end{minipage}\\
974     CN       &  $dimensionless$ &  1
975         &\begin{minipage}[t]{3in}
976          {Neutral Drag Coefficient}
977         \end{minipage}\\
978     WINDS     &  $m/sec$ &  1
979         &\begin{minipage}[t]{3in}
980          {Surface Wind Speed}
981         \end{minipage}\\
982     DTSRF     &  $deg$ &  1
983         &\begin{minipage}[t]{3in}
984          {Air/Surface virtual temperature difference}
985         \end{minipage}\\
986     TG        &  $deg$ &  1
987         &\begin{minipage}[t]{3in}
988          {Ground temperature}
989         \end{minipage}\\
990     TS        &  $deg$ &  1
991         &\begin{minipage}[t]{3in}
992          {Surface air temperature (Adiabatic from lowest model layer)}
993         \end{minipage}\\
994     DTG       &  $deg$ &  1
995         &\begin{minipage}[t]{3in}
996          {Ground temperature adjustment}
997         \end{minipage}\\
998    
999     QG        &  $g/kg$ &  1
1000         &\begin{minipage}[t]{3in}
1001          {Ground specific humidity}
1002         \end{minipage}\\
1003     QS        &  $g/kg$ &  1
1004         &\begin{minipage}[t]{3in}
1005          {Saturation surface specific humidity}
1006         \end{minipage}\\
1007     TGRLW    &    $deg$   &    1  
1008         &\begin{minipage}[t]{3in}
1009          {Instantaneous ground temperature used as input to the
1010           Longwave radiation subroutine}
1011         \end{minipage}\\
1012     ST4      &   $Watts/m^2$  &    1  
1013         &\begin{minipage}[t]{3in}
1014          {Upward Longwave flux at the ground ($\sigma T^4$)}
1015         \end{minipage}\\
1016     OLR      &   $Watts/m^2$  &    1  
1017         &\begin{minipage}[t]{3in}
1018          {Net upward Longwave flux at the top of the model}
1019         \end{minipage}\\
1020     OLRCLR   &   $Watts/m^2$  &    1  
1021         &\begin{minipage}[t]{3in}
1022          {Net upward clearsky Longwave flux at the top of the model}
1023         \end{minipage}\\
1024     LWGCLR   &   $Watts/m^2$  &    1  
1025         &\begin{minipage}[t]{3in}
1026          {Net upward clearsky Longwave flux at the ground}
1027         \end{minipage}\\
1028     LWCLR    &  $deg/day$ &  Nrphys
1029         &\begin{minipage}[t]{3in}
1030          {Net clearsky Longwave heating rate for each level}
1031         \end{minipage}\\
1032     TLW      &    $deg$   &  Nrphys
1033         &\begin{minipage}[t]{3in}
1034          {Instantaneous temperature used as input to the Longwave radiation
1035          subroutine}
1036         \end{minipage}\\
1037     SHLW     &    $g/g$   &  Nrphys
1038         &\begin{minipage}[t]{3in}
1039          {Instantaneous specific humidity used as input to the Longwave radiation
1040          subroutine}
1041         \end{minipage}\\
1042     OZLW     &    $g/g$   &  Nrphys
1043         &\begin{minipage}[t]{3in}
1044          {Instantaneous ozone used as input to the Longwave radiation
1045          subroutine}
1046         \end{minipage}\\
1047     CLMOLW   &    $0-1$   &  Nrphys
1048         &\begin{minipage}[t]{3in}
1049          {Maximum overlap cloud fraction used in the Longwave radiation
1050          subroutine}
1051         \end{minipage}\\
1052     CLDTOT   &    $0-1$   &  Nrphys
1053         &\begin{minipage}[t]{3in}
1054          {Total cloud fraction used in the Longwave and Shortwave radiation
1055          subroutines}
1056         \end{minipage}\\
1057     LWGDOWN  &    $Watts/m^2$   &  1
1058         &\begin{minipage}[t]{3in}
1059          {Downwelling Longwave radiation at the ground}
1060         \end{minipage}\\
1061     GWDT     &    $deg/day$ &  Nrphys
1062         &\begin{minipage}[t]{3in}
1063          {Temperature tendency due to Gravity Wave Drag}
1064         \end{minipage}\\
1065     RADSWT   &    $Watts/m^2$   &  1
1066         &\begin{minipage}[t]{3in}
1067          {Incident Shortwave radiation at the top of the atmosphere}
1068         \end{minipage}\\
1069     TAUCLD   &    $per 100 mb$   &  Nrphys
1070         &\begin{minipage}[t]{3in}
1071          {Counted Cloud Optical Depth (non-dimensional) per 100 mb}
1072         \end{minipage}\\
1073     TAUCLDC  &    $Number$   &  Nrphys
1074         &\begin{minipage}[t]{3in}
1075          {Cloud Optical Depth Counter}
1076         \end{minipage}\\
1077    \end{tabular}
1078    \vfill
1079    
1080    \newpage
1081    \vspace*{\fill}
1082    \begin{tabular}{llll}
1083    \hline\hline
1084     NAME & UNITS & LEVELS & DESCRIPTION \\
1085    \hline
1086    
1087    &\\
1088     CLDLOW   &    $0-1$   &  Nrphys
1089         &\begin{minipage}[t]{3in}
1090          {Low-Level ( 1000-700 hPa) Cloud Fraction  (0-1)}
1091         \end{minipage}\\
1092     EVAP     &    $mm/day$   &  1
1093         &\begin{minipage}[t]{3in}
1094          {Surface evaporation}
1095         \end{minipage}\\
1096     DPDT     &    $hPa/day$ &  1
1097         &\begin{minipage}[t]{3in}
1098          {Surface Pressure tendency}
1099         \end{minipage}\\
1100     UAVE     &    $m/sec$ &  Nrphys
1101         &\begin{minipage}[t]{3in}
1102          {Average U-Wind}
1103         \end{minipage}\\
1104     VAVE     &    $m/sec$ &  Nrphys
1105         &\begin{minipage}[t]{3in}
1106          {Average V-Wind}
1107         \end{minipage}\\
1108     TAVE     &    $deg$ &  Nrphys
1109         &\begin{minipage}[t]{3in}
1110          {Average Temperature}
1111         \end{minipage}\\
1112     QAVE     &    $g/kg$ &  Nrphys
1113         &\begin{minipage}[t]{3in}
1114          {Average Specific Humidity}
1115         \end{minipage}\\
1116     OMEGA    &    $hPa/day$ &  Nrphys
1117         &\begin{minipage}[t]{3in}
1118          {Vertical Velocity}
1119         \end{minipage}\\
1120     DUDT     &    $m/sec/day$ &  Nrphys
1121         &\begin{minipage}[t]{3in}
1122          {Total U-Wind tendency}
1123         \end{minipage}\\
1124     DVDT     &    $m/sec/day$ &  Nrphys
1125         &\begin{minipage}[t]{3in}
1126          {Total V-Wind tendency}
1127         \end{minipage}\\
1128     DTDT     &    $deg/day$ &  Nrphys
1129         &\begin{minipage}[t]{3in}
1130          {Total Temperature tendency}
1131         \end{minipage}\\
1132     DQDT     &    $g/kg/day$ &  Nrphys
1133         &\begin{minipage}[t]{3in}
1134          {Total Specific Humidity tendency}
1135         \end{minipage}\\
1136     VORT     &    $10^{-4}/sec$ &  Nrphys
1137         &\begin{minipage}[t]{3in}
1138          {Relative Vorticity}
1139         \end{minipage}\\
1140     DTLS     &    $deg/day$ &  Nrphys
1141         &\begin{minipage}[t]{3in}
1142          {Temperature tendency due to Stratiform Cloud Formation}
1143         \end{minipage}\\
1144     DQLS     &    $g/kg/day$ &  Nrphys
1145         &\begin{minipage}[t]{3in}
1146          {Specific Humidity tendency due to Stratiform Cloud Formation}
1147         \end{minipage}\\
1148     USTAR    &    $m/sec$ &  1
1149         &\begin{minipage}[t]{3in}
1150          {Surface USTAR wind}
1151         \end{minipage}\\
1152     Z0       &    $m$ &  1
1153         &\begin{minipage}[t]{3in}
1154          {Surface roughness}
1155         \end{minipage}\\
1156     FRQTRB   &    $0-1$ &  Nrphys-1
1157         &\begin{minipage}[t]{3in}
1158          {Frequency of Turbulence}
1159         \end{minipage}\\
1160     PBL      &    $mb$ &  1
1161         &\begin{minipage}[t]{3in}
1162          {Planetary Boundary Layer depth}
1163         \end{minipage}\\
1164     SWCLR    &  $deg/day$ &  Nrphys
1165         &\begin{minipage}[t]{3in}
1166          {Net clearsky Shortwave heating rate for each level}
1167         \end{minipage}\\
1168     OSR      &   $Watts/m^2$  &    1
1169         &\begin{minipage}[t]{3in}
1170          {Net downward Shortwave flux at the top of the model}
1171         \end{minipage}\\
1172     OSRCLR   &   $Watts/m^2$  &    1  
1173         &\begin{minipage}[t]{3in}
1174          {Net downward clearsky Shortwave flux at the top of the model}
1175         \end{minipage}\\
1176     CLDMAS   &   $kg / m^2$  &    Nrphys
1177         &\begin{minipage}[t]{3in}
1178          {Convective cloud mass flux}
1179         \end{minipage}\\
1180     UAVE     &   $m/sec$  &    Nrphys
1181         &\begin{minipage}[t]{3in}
1182          {Time-averaged $u-Wind$}
1183         \end{minipage}\\
1184    \end{tabular}
1185    \vfill
1186    
1187    \newpage
1188    \vspace*{\fill}
1189    \begin{tabular}{llll}
1190    \hline\hline
1191     NAME & UNITS & LEVELS & DESCRIPTION \\
1192    \hline
1193    
1194    &\\
1195     VAVE     &   $m/sec$  &    Nrphys
1196         &\begin{minipage}[t]{3in}
1197          {Time-averaged $v-Wind$}
1198         \end{minipage}\\
1199     TAVE     &   $deg$  &    Nrphys
1200         &\begin{minipage}[t]{3in}
1201          {Time-averaged $Temperature$}
1202         \end{minipage}\\
1203     QAVE     &   $g/g$  &    Nrphys
1204         &\begin{minipage}[t]{3in}
1205          {Time-averaged $Specific \, \, Humidity$}
1206         \end{minipage}\\
1207     RFT      &    $deg/day$ &  Nrphys
1208         &\begin{minipage}[t]{3in}
1209          {Temperature tendency due Rayleigh Friction}
1210         \end{minipage}\\
1211     PS       &   $mb$  &    1
1212         &\begin{minipage}[t]{3in}
1213          {Surface Pressure}
1214         \end{minipage}\\
1215     QQAVE    &   $(m/sec)^2$  &    Nrphys
1216         &\begin{minipage}[t]{3in}
1217          {Time-averaged $Turbulent Kinetic Energy$}
1218         \end{minipage}\\
1219     SWGCLR   &   $Watts/m^2$  &    1  
1220         &\begin{minipage}[t]{3in}
1221          {Net downward clearsky Shortwave flux at the ground}
1222         \end{minipage}\\
1223     PAVE     &   $mb$  &    1
1224         &\begin{minipage}[t]{3in}
1225          {Time-averaged Surface Pressure}
1226         \end{minipage}\\
1227     DIABU    & $m/sec/day$ &    Nrphys
1228         &\begin{minipage}[t]{3in}
1229          {Total Diabatic forcing on $u-Wind$}
1230         \end{minipage}\\
1231     DIABV    & $m/sec/day$ &    Nrphys
1232         &\begin{minipage}[t]{3in}
1233          {Total Diabatic forcing on $v-Wind$}
1234         \end{minipage}\\
1235     DIABT    & $deg/day$ &    Nrphys
1236         &\begin{minipage}[t]{3in}
1237          {Total Diabatic forcing on $Temperature$}
1238         \end{minipage}\\
1239     DIABQ    & $g/kg/day$ &    Nrphys
1240         &\begin{minipage}[t]{3in}
1241          {Total Diabatic forcing on $Specific \, \, Humidity$}
1242         \end{minipage}\\
1243     RFU      &    $m/sec/day$ &  Nrphys
1244         &\begin{minipage}[t]{3in}
1245          {U-Wind tendency due to Rayleigh Friction}
1246         \end{minipage}\\
1247     RFV      &    $m/sec/day$ &  Nrphys
1248         &\begin{minipage}[t]{3in}
1249          {V-Wind tendency due to Rayleigh Friction}
1250         \end{minipage}\\
1251     GWDU     &    $m/sec/day$ &  Nrphys
1252         &\begin{minipage}[t]{3in}
1253          {U-Wind tendency due to Gravity Wave Drag}
1254         \end{minipage}\\
1255     GWDU     &    $m/sec/day$ &  Nrphys
1256         &\begin{minipage}[t]{3in}
1257          {V-Wind tendency due to Gravity Wave Drag}
1258         \end{minipage}\\
1259     GWDUS    &    $N/m^2$ &  1
1260         &\begin{minipage}[t]{3in}
1261          {U-Wind Gravity Wave Drag Stress at Surface}
1262         \end{minipage}\\
1263     GWDVS    &    $N/m^2$ &  1
1264         &\begin{minipage}[t]{3in}
1265          {V-Wind Gravity Wave Drag Stress at Surface}
1266         \end{minipage}\\
1267     GWDUT    &    $N/m^2$ &  1
1268         &\begin{minipage}[t]{3in}
1269          {U-Wind Gravity Wave Drag Stress at Top}
1270         \end{minipage}\\
1271     GWDVT    &    $N/m^2$ &  1
1272         &\begin{minipage}[t]{3in}
1273          {V-Wind Gravity Wave Drag Stress at Top}
1274         \end{minipage}\\
1275     LZRAD    &    $mg/kg$ &  Nrphys
1276             &\begin{minipage}[t]{3in}
1277              {Estimated Cloud Liquid Water used in Radiation}
1278             \end{minipage}\\
1279    \end{tabular}
1280    \vfill
1281    
1282    \newpage
1283    \vspace*{\fill}
1284    \begin{tabular}{llll}
1285    \hline\hline
1286     NAME & UNITS & LEVELS & DESCRIPTION \\
1287    \hline
1288    
1289    &\\
1290     SLP      &   $mb$  &    1
1291             &\begin{minipage}[t]{3in}
1292              {Time-averaged Sea-level Pressure}
1293             \end{minipage}\\
1294     CLDFRC  & $0-1$ &    1
1295             &\begin{minipage}[t]{3in}
1296              {Total Cloud Fraction}
1297             \end{minipage}\\
1298     TPW     & $gm/cm^2$ &    1
1299             &\begin{minipage}[t]{3in}
1300              {Precipitable water}
1301             \end{minipage}\\
1302     U2M     & $m/sec$ &    1
1303             &\begin{minipage}[t]{3in}
1304              {U-Wind at 2 meters}
1305             \end{minipage}\\
1306     V2M     & $m/sec$ &    1
1307             &\begin{minipage}[t]{3in}
1308              {V-Wind at 2 meters}
1309             \end{minipage}\\
1310     T2M     & $deg$ &    1
1311             &\begin{minipage}[t]{3in}
1312              {Temperature at 2 meters}
1313             \end{minipage}\\
1314     Q2M     & $g/kg$ &    1
1315             &\begin{minipage}[t]{3in}
1316              {Specific Humidity at 2 meters}
1317             \end{minipage}\\
1318     U10M    & $m/sec$ &    1
1319             &\begin{minipage}[t]{3in}
1320              {U-Wind at 10 meters}
1321             \end{minipage}\\
1322     V10M    & $m/sec$ &    1
1323             &\begin{minipage}[t]{3in}
1324              {V-Wind at 10 meters}
1325             \end{minipage}\\
1326     T10M    & $deg$ &    1
1327             &\begin{minipage}[t]{3in}
1328              {Temperature at 10 meters}
1329             \end{minipage}\\
1330     Q10M    & $g/kg$ &    1
1331             &\begin{minipage}[t]{3in}
1332              {Specific Humidity at 10 meters}
1333             \end{minipage}\\
1334     DTRAIN  & $kg/m^2$ &    Nrphys
1335             &\begin{minipage}[t]{3in}
1336              {Detrainment Cloud Mass Flux}
1337             \end{minipage}\\
1338     QFILL   & $g/kg/day$ &    Nrphys
1339             &\begin{minipage}[t]{3in}
1340              {Filling of negative specific humidity}
1341             \end{minipage}\\
1342    \end{tabular}
1343    \vspace{1.5in}
1344    \vfill
1345    
1346    \newpage
1347    \vspace*{\fill}
1348    \begin{tabular}{llll}
1349    \hline\hline
1350     NAME & UNITS & LEVELS & DESCRIPTION \\
1351    \hline
1352    
1353    &\\
1354     DTCONV   & $deg/sec$ & Nr
1355             &\begin{minipage}[t]{3in}
1356              {Temp Change due to Convection}
1357             \end{minipage}\\
1358     DQCONV   & $g/kg/sec$ & Nr
1359             &\begin{minipage}[t]{3in}
1360              {Specific Humidity Change due to Convection}
1361             \end{minipage}\\
1362     RELHUM   & $percent$ & Nr
1363             &\begin{minipage}[t]{3in}
1364              {Relative Humidity}
1365             \end{minipage}\\
1366     PRECLS   & $g/m^2/sec$ & 1
1367             &\begin{minipage}[t]{3in}
1368              {Large Scale Precipitation}
1369             \end{minipage}\\
1370     ENPREC   & $J/g$ & 1
1371             &\begin{minipage}[t]{3in}
1372              {Energy of Precipitation (snow, rain Temp)}
1373             \end{minipage}\\
1374    \end{tabular}
1375    \vspace{1.5in}
1376    \vfill
1377    
1378    \newpage
1379    
1380    Fizhi Diagnostic Description:
1381    
1382    In this section we list and describe the diagnostic quantities available within the
1383    GCM.  The diagnostics are listed in the order that they appear in the
1384    Diagnostic Menu, Section \ref{sec:fizhi-diagnostics:menu}.
1385    In all cases, each diagnostic as currently archived on the output datasets
1386    is time-averaged over its diagnostic output frequency:
1387    
1388    \[
1389    {\bf DIAGNOSTIC} = {1 \over TTOT} \sum_{t=1}^{t=TTOT} diag(t)
1390    \]
1391    where $TTOT = {{\bf NQDIAG} \over \Delta t}$, {\bf NQDIAG} is the
1392    output frequency of the diagnostic, and $\Delta t$ is
1393    the timestep over which the diagnostic is updated.  
1394    
1395    { \underline {UFLUX} Surface Zonal Wind Stress on the Atmosphere ($Newton/m^2$) }
1396    
1397    The zonal wind stress is the turbulent flux of zonal momentum from
1398    the surface.
1399    \[
1400    {\bf UFLUX} =  - \rho C_D W_s u \hspace{1cm}where: \hspace{.2cm}C_D = C^2_u
1401    \]
1402    where $\rho$ = the atmospheric density at the surface, $C_{D}$ is the surface
1403    drag coefficient, $C_u$ is the dimensionless surface exchange coefficient for momentum
1404    (see diagnostic number 10), $W_s$ is the magnitude of the surface layer wind, and $u$ is
1405    the zonal wind in the lowest model layer.
1406    \\
1407    
1408    
1409    { \underline {VFLUX} Surface Meridional Wind Stress on the Atmosphere ($Newton/m^2$) }
1410    
1411    The meridional wind stress is the turbulent flux of meridional momentum from
1412    the surface.
1413    \[
1414    {\bf VFLUX} =  - \rho C_D W_s v \hspace{1cm}where: \hspace{.2cm}C_D = C^2_u
1415    \]
1416    where $\rho$ = the atmospheric density at the surface, $C_{D}$ is the surface
1417    drag coefficient, $C_u$ is the dimensionless surface exchange coefficient for momentum
1418    (see diagnostic number 10), $W_s$ is the magnitude of the surface layer wind, and $v$ is
1419    the meridional wind in the lowest model layer.
1420    \\
1421    
1422    { \underline {HFLUX} Surface Flux of Sensible Heat ($Watts/m^2$) }
1423    
1424    The turbulent flux of sensible heat from the surface to the atmosphere is a function of the
1425    gradient of virtual potential temperature and the eddy exchange coefficient:
1426    \[
1427    {\bf HFLUX} =  P^{\kappa}\rho c_{p} C_{H} W_s (\theta_{surface} - \theta_{Nrphys})
1428    \hspace{1cm}where: \hspace{.2cm}C_H = C_u C_t
1429    \]
1430    where $\rho$ = the atmospheric density at the surface, $c_{p}$ is the specific
1431    heat of air, $C_{H}$ is the dimensionless surface heat transfer coefficient, $W_s$ is the
1432    magnitude of the surface layer wind, $C_u$ is the dimensionless surface exchange coefficient
1433    for momentum (see diagnostic number 10), $C_t$ is the dimensionless surface exchange coefficient
1434    for heat and moisture (see diagnostic number 9), and $\theta$ is the potential temperature
1435    at the surface and at the bottom model level.
1436    \\
1437    
1438    
1439    { \underline {EFLUX} Surface Flux of Latent Heat ($Watts/m^2$) }
1440    
1441    The turbulent flux of latent heat from the surface to the atmosphere is a function of the
1442    gradient of moisture, the potential evapotranspiration fraction and the eddy exchange coefficient:
1443    \[
1444    {\bf EFLUX} =  \rho \beta L C_{H} W_s (q_{surface} - q_{Nrphys})
1445    \hspace{1cm}where: \hspace{.2cm}C_H = C_u C_t
1446    \]
1447    where $\rho$ = the atmospheric density at the surface, $\beta$ is the fraction of
1448    the potential evapotranspiration actually evaporated, L is the latent
1449    heat of evaporation, $C_{H}$ is the dimensionless surface heat transfer coefficient, $W_s$ is the
1450    magnitude of the surface layer wind, $C_u$ is the dimensionless surface exchange coefficient
1451    for momentum (see diagnostic number 10), $C_t$ is the dimensionless surface exchange coefficient
1452    for heat and moisture (see diagnostic number 9), and $q_{surface}$ and $q_{Nrphys}$ are the specific
1453    humidity at the surface and at the bottom model level, respectively.
1454    \\
1455    
1456    { \underline {QICE} Heat Conduction Through Sea Ice ($Watts/m^2$) }
1457    
1458    Over sea ice there is an additional source of energy at the surface due to the heat
1459    conduction from the relatively warm ocean through the sea ice. The heat conduction
1460    through sea ice represents an additional energy source term for the ground temperature equation.
1461    
1462    \[
1463    {\bf QICE} = {C_{ti} \over {H_i}} (T_i-T_g)
1464    \]
1465    
1466    where $C_{ti}$ is the thermal conductivity of ice, $H_i$ is the ice thickness, assumed to
1467    be $3 \hspace{.1cm} m$ where sea ice is present, $T_i$ is 273 degrees Kelvin, and
1468    $T_g$ is the temperature of the sea ice.
1469    
1470    NOTE: QICE is not available through model version 5.3, but is available in subsequent versions.
1471    \\
1472    
1473    
1474    { \underline {RADLWG} Net upward Longwave Flux at the surface ($Watts/m^2$)}
1475    
1476    \begin{eqnarray*}
1477    {\bf RADLWG} & =  & F_{LW,Nrphys+1}^{Net} \\
1478                 & =  & F_{LW,Nrphys+1}^\uparrow - F_{LW,Nrphys+1}^\downarrow
1479    \end{eqnarray*}
1480    \\
1481    where Nrphys+1 indicates the lowest model edge-level, or $p = p_{surf}$.
1482    $F_{LW}^\uparrow$ is
1483    the upward Longwave flux and $F_{LW}^\downarrow$ is the downward Longwave flux.
1484    \\
1485    
1486    { \underline {RADSWG} Net downard shortwave Flux at the surface ($Watts/m^2$)}
1487    
1488    \begin{eqnarray*}
1489    {\bf RADSWG} & =  & F_{SW,Nrphys+1}^{Net} \\
1490                 & =  & F_{SW,Nrphys+1}^\downarrow - F_{SW,Nrphys+1}^\uparrow
1491    \end{eqnarray*}
1492    \\
1493    where Nrphys+1 indicates the lowest model edge-level, or $p = p_{surf}$.
1494    $F_{SW}^\downarrow$ is
1495    the downward Shortwave flux and $F_{SW}^\uparrow$ is the upward Shortwave flux.
1496    \\
1497    
1498    
1499    \noindent
1500    { \underline {RI} Richardson Number} ($dimensionless$)
1501    
1502    \noindent
1503    The non-dimensional stability indicator is the ratio of the buoyancy to the shear:
1504    \[
1505    {\bf RI} = { { {g \over \theta_v} \pp {\theta_v}{z} } \over { (\pp{u}{z})^2 + (\pp{v}{z})^2 } }
1506     =  {  {c_p \pp{\theta_v}{z} \pp{P^ \kappa}{z} } \over { (\pp{u}{z})^2 + (\pp{v}{z})^2 } }
1507    \]
1508    \\
1509    where we used the hydrostatic equation:
1510    \[
1511    {\pp{\Phi}{P^ \kappa}} = c_p \theta_v
1512    \]
1513    Negative values indicate unstable buoyancy {\bf{AND}} shear, small positive values ($<0.4$)
1514    indicate dominantly unstable shear, and large positive values indicate dominantly stable
1515    stratification.
1516    \\
1517    
1518    \noindent
1519    { \underline {CT}  Surface Exchange Coefficient for Temperature and Moisture ($dimensionless$) }
1520    
1521    \noindent
1522    The surface exchange coefficient is obtained from the similarity functions for the stability
1523     dependant flux profile relationships:
1524    \[
1525    {\bf CT} = -{( {\overline{w^{\prime}\theta^{\prime}}}) \over {u_* \Delta \theta }} =
1526    -{( {\overline{w^{\prime}q^{\prime}}}) \over {u_* \Delta q }} =
1527    { k \over { (\psi_{h} + \psi_{g}) } }
1528    \]
1529    where $\psi_h$ is the surface layer non-dimensional temperature change and $\psi_g$ is the
1530    viscous sublayer non-dimensional temperature or moisture change:
1531    \[
1532    \psi_{h} = {\int_{\zeta_{0}}^{\zeta} {\phi_{h} \over \zeta} d \zeta} \hspace{1cm} and
1533    \hspace{1cm} \psi_{g} = { 0.55 (Pr^{2/3} - 0.2) \over \nu^{1/2} }
1534    (h_{0}u_{*} - h_{0_{ref}}u_{*_{ref}})^{1/2}
1535    \]
1536    and:
1537    $h_{0} = 30z_{0}$ with a maximum value over land of 0.01
1538    
1539    \noindent
1540    $\phi_h$ is the similarity function of $\zeta$, which expresses the stability dependance of
1541    the temperature and moisture gradients, specified differently for stable and unstable
1542    layers according to \cite{helfschu:95}. k is the Von Karman constant, $\zeta$ is the
1543    non-dimensional stability parameter, Pr is the Prandtl number for air, $\nu$ is the molecular
1544    viscosity, $z_{0}$ is the surface roughness length, $u_*$ is the surface stress velocity
1545    (see diagnostic number 67), and the subscript ref refers to a reference value.
1546    \\
1547    
1548    \noindent
1549    { \underline {CU}  Surface Exchange Coefficient for Momentum ($dimensionless$) }
1550    
1551    \noindent
1552    The surface exchange coefficient is obtained from the similarity functions for the stability
1553     dependant flux profile relationships:
1554    \[
1555    {\bf CU} = {u_* \over W_s} = { k \over \psi_{m} }
1556    \]
1557    where $\psi_m$ is the surface layer non-dimensional wind shear:
1558    \[
1559    \psi_{m} = {\int_{\zeta_{0}}^{\zeta} {\phi_{m} \over \zeta} d \zeta}
1560    \]
1561    \noindent
1562    $\phi_m$ is the similarity function of $\zeta$, which expresses the stability dependance of
1563    the temperature and moisture gradients, specified differently for stable and unstable layers
1564    according to \cite{helfschu:95}. k is the Von Karman constant, $\zeta$ is the
1565    non-dimensional stability parameter, $u_*$ is the surface stress velocity
1566    (see diagnostic number 67), and $W_s$ is the magnitude of the surface layer wind.
1567    \\
1568    
1569    \noindent
1570    { \underline {ET}  Diffusivity Coefficient for Temperature and Moisture ($m^2/sec$) }
1571    
1572    \noindent
1573    In the level 2.5 version of the Mellor-Yamada (1974) hierarchy, the turbulent heat or
1574    moisture flux for the atmosphere above the surface layer can be expressed as a turbulent
1575    diffusion coefficient $K_h$ times the negative of the gradient of potential temperature
1576    or moisture. In the \cite{helflab:88} adaptation of this closure, $K_h$
1577    takes the form:
1578    \[
1579    {\bf ET} = K_h = -{( {\overline{w^{\prime}\theta_v^{\prime}}}) \over {\pp{\theta_v}{z}} }
1580     = \left\{ \begin{array}{l@{\quad\mbox{for}\quad}l} q \, \ell \, S_H(G_M,G_H) & \mbox{decaying turbulence}
1581    \\ { q^2 \over {q_e} } \, \ell \, S_{H}(G_{M_e},G_{H_e}) & \mbox{growing turbulence} \end{array} \right.
1582    \]
1583    where $q$ is the turbulent velocity, or $\sqrt{2*turbulent \hspace{.2cm} kinetic \hspace{.2cm}
1584    energy}$, $q_e$ is the turbulence velocity derived from the more simple level 2.0 model,
1585    which describes equilibrium turbulence, $\ell$ is the master length scale related to the layer
1586    depth,
1587    $S_H$ is a function of $G_H$ and $G_M$, the dimensionless buoyancy and
1588    wind shear parameters, respectively, or a function of $G_{H_e}$ and $G_{M_e}$, the equilibrium
1589    dimensionless buoyancy and wind shear
1590    parameters.   Both $G_H$ and $G_M$, and their equilibrium values $G_{H_e}$ and $G_{M_e}$,
1591    are functions of the Richardson number.
1592    
1593    \noindent
1594    For the detailed equations and derivations of the modified level 2.5 closure scheme,
1595    see \cite{helflab:88}.
1596    
1597    \noindent
1598    In the surface layer, ${\bf {ET}}$ is the exchange coefficient for heat and moisture,
1599    in units of $m/sec$, given by:
1600    \[
1601    {\bf ET_{Nrphys}} =  C_t * u_* = C_H W_s
1602    \]
1603    \noindent
1604    where $C_t$ is the dimensionless exchange coefficient for heat and moisture from the
1605    surface layer similarity functions (see diagnostic number 9), $u_*$ is the surface
1606    friction velocity (see diagnostic number 67), $C_H$ is the heat transfer coefficient,
1607    and $W_s$ is the magnitude of the surface layer wind.
1608    \\
1609    
1610    \noindent
1611    { \underline {EU}  Diffusivity Coefficient for Momentum ($m^2/sec$) }
1612    
1613    \noindent  
1614    In the level 2.5 version of the Mellor-Yamada (1974) hierarchy, the turbulent heat
1615    momentum flux for the atmosphere above the surface layer can be expressed as a turbulent
1616    diffusion coefficient $K_m$ times the negative of the gradient of the u-wind.
1617    In the \cite{helflab:88} adaptation of this closure, $K_m$
1618    takes the form:
1619    \[
1620    {\bf EU} = K_m = -{( {\overline{u^{\prime}w^{\prime}}}) \over {\pp{U}{z}} }
1621     = \left\{ \begin{array}{l@{\quad\mbox{for}\quad}l} q \, \ell \, S_M(G_M,G_H) & \mbox{decaying turbulence}
1622    \\ { q^2 \over {q_e} } \, \ell \, S_{M}(G_{M_e},G_{H_e}) & \mbox{growing turbulence} \end{array} \right.
1623    \]
1624    \noindent
1625    where $q$ is the turbulent velocity, or $\sqrt{2*turbulent \hspace{.2cm} kinetic \hspace{.2cm}
1626    energy}$, $q_e$ is the turbulence velocity derived from the more simple level 2.0 model,
1627    which describes equilibrium turbulence, $\ell$ is the master length scale related to the layer
1628    depth,
1629    $S_M$ is a function of $G_H$ and $G_M$, the dimensionless buoyancy and
1630    wind shear parameters, respectively, or a function of $G_{H_e}$ and $G_{M_e}$, the equilibrium
1631    dimensionless buoyancy and wind shear
1632    parameters.   Both $G_H$ and $G_M$, and their equilibrium values $G_{H_e}$ and $G_{M_e}$,
1633    are functions of the Richardson number.
1634    
1635    \noindent
1636    For the detailed equations and derivations of the modified level 2.5 closure scheme,
1637    see \cite{helflab:88}.
1638    
1639    \noindent
1640    In the surface layer, ${\bf {EU}}$ is the exchange coefficient for momentum,
1641    in units of $m/sec$, given by:
1642    \[
1643    {\bf EU_{Nrphys}} = C_u * u_* = C_D W_s
1644    \]
1645    \noindent
1646    where $C_u$ is the dimensionless exchange coefficient for momentum from the surface layer
1647    similarity functions (see diagnostic number 10), $u_*$ is the surface friction velocity
1648    (see diagnostic number 67), $C_D$ is the surface drag coefficient, and $W_s$ is the
1649    magnitude of the surface layer wind.
1650    \\
1651    
1652    \noindent
1653    { \underline {TURBU}  Zonal U-Momentum changes due to Turbulence ($m/sec/day$) }
1654    
1655    \noindent
1656    The tendency of U-Momentum due to turbulence is written:
1657    \[
1658    {\bf TURBU} = {\pp{u}{t}}_{turb} = {\pp{}{z} }{(- \overline{u^{\prime}w^{\prime}})}
1659     = {\pp{}{z} }{(K_m \pp{u}{z})}
1660    \]
1661    
1662    \noindent
1663    The Helfand and Labraga level 2.5 scheme models the turbulent
1664    flux of u-momentum in terms of $K_m$, and the equation has the form of a diffusion
1665    equation.
1666    
1667    \noindent
1668    { \underline {TURBV}  Meridional V-Momentum changes due to Turbulence ($m/sec/day$) }
1669    
1670    \noindent
1671    The tendency of V-Momentum due to turbulence is written:
1672    \[
1673    {\bf TURBV} = {\pp{v}{t}}_{turb} = {\pp{}{z} }{(- \overline{v^{\prime}w^{\prime}})}
1674     = {\pp{}{z} }{(K_m \pp{v}{z})}
1675    \]
1676    
1677    \noindent
1678    The Helfand and Labraga level 2.5 scheme models the turbulent
1679    flux of v-momentum in terms of $K_m$, and the equation has the form of a diffusion
1680    equation.
1681    \\
1682    
1683    \noindent
1684    { \underline {TURBT}  Temperature changes due to Turbulence ($deg/day$) }
1685    
1686    \noindent
1687    The tendency of temperature due to turbulence is written:
1688    \[
1689    {\bf TURBT} = {\pp{T}{t}} = P^{\kappa}{\pp{\theta}{t}}_{turb} =
1690    P^{\kappa}{\pp{}{z} }{(- \overline{w^{\prime}\theta^{\prime}})}
1691     = P^{\kappa}{\pp{}{z} }{(K_h \pp{\theta_v}{z})}
1692    \]
1693    
1694    \noindent
1695    The Helfand and Labraga level 2.5 scheme models the turbulent
1696    flux of temperature in terms of $K_h$, and the equation has the form of a diffusion
1697    equation.
1698    \\
1699    
1700    \noindent
1701    { \underline {TURBQ}  Specific Humidity changes due to Turbulence ($g/kg/day$) }
1702    
1703    \noindent
1704    The tendency of specific humidity due to turbulence is written:
1705    \[
1706    {\bf TURBQ} = {\pp{q}{t}}_{turb} = {\pp{}{z} }{(- \overline{w^{\prime}q^{\prime}})}
1707     = {\pp{}{z} }{(K_h \pp{q}{z})}
1708    \]
1709    
1710    \noindent
1711    The Helfand and Labraga level 2.5 scheme models the turbulent
1712    flux of temperature in terms of $K_h$, and the equation has the form of a diffusion
1713    equation.
1714    \\
1715    
1716    \noindent
1717    { \underline {MOISTT} Temperature Changes Due to Moist Processes ($deg/day$) }
1718    
1719    \noindent
1720    \[
1721    {\bf MOISTT} = \left. {\pp{T}{t}}\right|_{c} + \left. {\pp{T}{t}} \right|_{ls}
1722    \]
1723    where:
1724    \[
1725    \left.{\pp{T}{t}}\right|_{c} = R \sum_i \left( \alpha { m_B \over c_p} \Gamma_s \right)_i
1726    \hspace{.4cm} and
1727    \hspace{.4cm} \left.{\pp{T}{t}}\right|_{ls} = {L \over c_p } (q^*-q)
1728    \]
1729    and
1730    \[
1731    \Gamma_s = g \eta \pp{s}{p}
1732    \]
1733    
1734    \noindent
1735    The subscript $c$ refers to convective processes, while the subscript $ls$ refers to large scale
1736    precipitation processes, or supersaturation rain.
1737    The summation refers to contributions from each cloud type called by RAS.  
1738    The dry static energy is given
1739    as $s$, the convective cloud base mass flux is given as $m_B$, and the cloud entrainment is
1740    given as $\eta$, which are explicitly defined in Section \ref{sec:fizhi:mc},
1741    the description of the convective parameterization.  The fractional adjustment, or relaxation
1742    parameter, for each cloud type is given as $\alpha$, while
1743    $R$ is the rain re-evaporation adjustment.
1744    \\
1745    
1746    \noindent
1747    { \underline {MOISTQ} Specific Humidity Changes Due to Moist Processes ($g/kg/day$) }
1748    
1749    \noindent
1750    \[
1751    {\bf MOISTQ} = \left. {\pp{q}{t}}\right|_{c} + \left. {\pp{q}{t}} \right|_{ls}
1752    \]
1753    where:
1754    \[
1755    \left.{\pp{q}{t}}\right|_{c} = R \sum_i \left( \alpha { m_B \over {L}}(\Gamma_h-\Gamma_s) \right)_i
1756    \hspace{.4cm} and
1757    \hspace{.4cm} \left.{\pp{q}{t}}\right|_{ls} = (q^*-q)
1758    \]
1759    and
1760    \[
1761    \Gamma_s = g \eta \pp{s}{p}\hspace{.4cm} and \hspace{.4cm}\Gamma_h = g \eta \pp{h}{p}
1762    \]
1763    \noindent
1764    The subscript $c$ refers to convective processes, while the subscript $ls$ refers to large scale
1765    precipitation processes, or supersaturation rain.
1766    The summation refers to contributions from each cloud type called by RAS.  
1767    The dry static energy is given as $s$,
1768    the moist static energy is given as $h$,
1769    the convective cloud base mass flux is given as $m_B$, and the cloud entrainment is
1770    given as $\eta$, which are explicitly defined in Section \ref{sec:fizhi:mc},
1771    the description of the convective parameterization.  The fractional adjustment, or relaxation
1772    parameter, for each cloud type is given as $\alpha$, while
1773    $R$ is the rain re-evaporation adjustment.
1774    \\
1775    
1776    \noindent
1777    { \underline {RADLW} Heating Rate due to Longwave Radiation ($deg/day$) }
1778    
1779    \noindent
1780    The net longwave heating rate is calculated as the vertical divergence of the
1781    net terrestrial radiative fluxes.
1782    Both the clear-sky and cloudy-sky longwave fluxes are computed within the
1783    longwave routine.
1784    The subroutine calculates the clear-sky flux, $F^{clearsky}_{LW}$, first.
1785    For a given cloud fraction,
1786    the clear line-of-sight probability $C(p,p^{\prime})$ is computed from the current level pressure $p$
1787    to the model top pressure, $p^{\prime} = p_{top}$, and the model surface pressure, $p^{\prime} = p_{surf}$,
1788    for the upward and downward radiative fluxes.
1789    (see Section \ref{sec:fizhi:radcloud}).
1790    The cloudy-sky flux is then obtained as:
1791      
1792    \noindent
1793    \[
1794    F_{LW} = C(p,p') \cdot F^{clearsky}_{LW},
1795    \]
1796    
1797    \noindent
1798    Finally, the net longwave heating rate is calculated as the vertical divergence of the
1799    net terrestrial radiative fluxes:
1800    \[
1801    \pp{\rho c_p T}{t} = - {\partial \over \partial z} F_{LW}^{NET} ,
1802    \]
1803    or
1804    \[
1805    {\bf RADLW} = \frac{g}{c_p \pi} {\partial \over \partial \sigma} F_{LW}^{NET} .
1806    \]
1807    
1808    \noindent
1809    where $g$ is the accelation due to gravity,
1810    $c_p$ is the heat capacity of air at constant pressure,
1811    and
1812    \[
1813    F_{LW}^{NET} = F_{LW}^\uparrow - F_{LW}^\downarrow
1814    \]
1815    \\
1816    
1817    
1818    \noindent
1819    { \underline {RADSW} Heating Rate due to Shortwave Radiation ($deg/day$) }
1820    
1821    \noindent
1822    The net Shortwave heating rate is calculated as the vertical divergence of the
1823    net solar radiative fluxes.
1824    The clear-sky and cloudy-sky shortwave fluxes are calculated separately.
1825    For the clear-sky case, the shortwave fluxes and heating rates are computed with
1826    both CLMO (maximum overlap cloud fraction) and
1827    CLRO (random overlap cloud fraction) set to zero (see Section \ref{sec:fizhi:radcloud}).
1828    The shortwave routine is then called a second time, for the cloudy-sky case, with the
1829    true time-averaged cloud fractions CLMO
1830    and CLRO being used.  In all cases, a normalized incident shortwave flux is used as
1831    input at the top of the atmosphere.
1832    
1833    \noindent
1834    The heating rate due to Shortwave Radiation under cloudy skies is defined as:
1835    \[
1836    \pp{\rho c_p T}{t} = - {\partial \over \partial z} F(cloudy)_{SW}^{NET} \cdot {\rm RADSWT},
1837    \]
1838    or
1839    \[
1840    {\bf RADSW} = \frac{g}{c_p \pi} {\partial \over \partial \sigma} F(cloudy)_{SW}^{NET}\cdot {\rm RADSWT} .
1841    \]
1842    
1843    \noindent
1844    where $g$ is the accelation due to gravity,
1845    $c_p$ is the heat capacity of air at constant pressure, RADSWT is the true incident
1846    shortwave radiation at the top of the atmosphere (See Diagnostic \#48), and
1847    \[
1848    F(cloudy)_{SW}^{Net} = F(cloudy)_{SW}^\uparrow - F(cloudy)_{SW}^\downarrow
1849    \]
1850    \\
1851    
1852    \noindent
1853    { \underline {PREACC} Total (Large-scale + Convective) Accumulated Precipition ($mm/day$) }
1854    
1855    \noindent
1856    For a change in specific humidity due to moist processes, $\Delta q_{moist}$,
1857    the vertical integral or total precipitable amount is given by:  
1858    \[
1859    {\bf PREACC} = \int_{surf}^{top} \rho \Delta q_{moist} dz = - \int_{surf}^{top} \Delta  q_{moist}
1860    {dp \over g} = {1 \over g} \int_0^1 \Delta q_{moist} dp
1861    \]
1862    \\
1863    
1864    \noindent
1865    A precipitation rate is defined as the vertically integrated moisture adjustment per Moist Processes
1866    time step, scaled to $mm/day$.
1867    \\
1868    
1869    \noindent
1870    { \underline {PRECON} Convective Precipition ($mm/day$) }
1871    
1872    \noindent
1873    For a change in specific humidity due to sub-grid scale cumulus convective processes, $\Delta q_{cum}$,
1874    the vertical integral or total precipitable amount is given by:  
1875    \[
1876    {\bf PRECON} = \int_{surf}^{top} \rho \Delta q_{cum} dz = - \int_{surf}^{top} \Delta  q_{cum}
1877    {dp \over g} = {1 \over g} \int_0^1 \Delta q_{cum} dp
1878    \]
1879    \\
1880    
1881    \noindent
1882    A precipitation rate is defined as the vertically integrated moisture adjustment per Moist Processes
1883    time step, scaled to $mm/day$.
1884    \\
1885    
1886    \noindent
1887    { \underline {TUFLUX}  Turbulent Flux of U-Momentum ($Newton/m^2$) }
1888    
1889    \noindent
1890    The turbulent flux of u-momentum is calculated for $diagnostic \hspace{.2cm} purposes
1891     \hspace{.2cm} only$ from the eddy coefficient for momentum:
1892    
1893    \[
1894    {\bf TUFLUX} =  {\rho } {(\overline{u^{\prime}w^{\prime}})} =  
1895    {\rho } {(- K_m \pp{U}{z})}
1896    \]
1897    
1898    \noindent
1899    where $\rho$ is the air density, and $K_m$ is the eddy coefficient.
1900    \\
1901    
1902    \noindent
1903    { \underline {TVFLUX}  Turbulent Flux of V-Momentum ($Newton/m^2$) }
1904    
1905    \noindent
1906    The turbulent flux of v-momentum is calculated for $diagnostic \hspace{.2cm} purposes
1907    \hspace{.2cm} only$ from the eddy coefficient for momentum:
1908    
1909    \[
1910    {\bf TVFLUX} =  {\rho } {(\overline{v^{\prime}w^{\prime}})} =
1911     {\rho } {(- K_m \pp{V}{z})}
1912    \]
1913    
1914    \noindent
1915    where $\rho$ is the air density, and $K_m$ is the eddy coefficient.
1916    \\
1917    
1918    
1919    \noindent
1920    { \underline {TTFLUX}  Turbulent Flux of Sensible Heat ($Watts/m^2$) }
1921    
1922    \noindent
1923    The turbulent flux of sensible heat is calculated for $diagnostic \hspace{.2cm} purposes
1924    \hspace{.2cm} only$ from the eddy coefficient for heat and moisture:
1925    
1926    \noindent
1927    \[
1928    {\bf TTFLUX} = c_p {\rho }  
1929    P^{\kappa}{(\overline{w^{\prime}\theta^{\prime}})}
1930     = c_p  {\rho } P^{\kappa}{(- K_h \pp{\theta_v}{z})}
1931    \]
1932    
1933    \noindent
1934    where $\rho$ is the air density, and $K_h$ is the eddy coefficient.
1935    \\
1936    
1937    
1938    \noindent
1939    { \underline {TQFLUX}  Turbulent Flux of Latent Heat ($Watts/m^2$) }
1940    
1941    \noindent
1942    The turbulent flux of latent heat is calculated for $diagnostic \hspace{.2cm} purposes
1943    \hspace{.2cm} only$ from the eddy coefficient for heat and moisture:
1944    
1945    \noindent
1946    \[
1947    {\bf TQFLUX} = {L {\rho } (\overline{w^{\prime}q^{\prime}})} =
1948    {L {\rho }(- K_h \pp{q}{z})}
1949    \]
1950    
1951    \noindent
1952    where $\rho$ is the air density, and $K_h$ is the eddy coefficient.
1953    \\
1954    
1955    
1956    \noindent
1957    { \underline {CN}  Neutral Drag Coefficient ($dimensionless$) }
1958    
1959    \noindent
1960    The drag coefficient for momentum obtained by assuming a neutrally stable surface layer:
1961    \[
1962    {\bf CN} = { k \over { \ln({h \over {z_0}})} }
1963    \]
1964    
1965    \noindent
1966    where $k$ is the Von Karman constant, $h$ is the height of the surface layer, and
1967    $z_0$ is the surface roughness.
1968    
1969    \noindent
1970    NOTE: CN is not available through model version 5.3, but is available in subsequent
1971    versions.
1972    \\
1973    
1974    \noindent
1975    { \underline {WINDS}  Surface Wind Speed ($meter/sec$) }
1976    
1977    \noindent
1978    The surface wind speed is calculated for the last internal turbulence time step:
1979    \[
1980    {\bf WINDS} = \sqrt{u_{Nrphys}^2 + v_{Nrphys}^2}
1981    \]
1982    
1983    \noindent
1984    where the subscript $Nrphys$ refers to the lowest model level.
1985    \\
1986    
1987    \noindent
1988    { \underline {DTSRF}  Air/Surface Virtual Temperature Difference ($deg \hspace{.1cm} K$) }
1989    
1990    \noindent
1991    The air/surface virtual temperature difference measures the stability of the surface layer:
1992    \[
1993    {\bf DTSRF} = (\theta_{v{Nrphys+1}} - \theta{v_{Nrphys}}) P^{\kappa}_{surf}
1994    \]
1995    \noindent
1996    where
1997    \[
1998    \theta_{v{Nrphys+1}} = { T_g \over {P^{\kappa}_{surf}} } (1 + .609 q_{Nrphys+1}) \hspace{1cm}
1999    and \hspace{1cm} q_{Nrphys+1} = q_{Nrphys} + \beta(q^*(T_g,P_s) - q_{Nrphys})
2000    \]
2001    
2002    \noindent
2003    $\beta$ is the surface potential evapotranspiration coefficient ($\beta=1$ over oceans),
2004    $q^*(T_g,P_s)$ is the saturation specific humidity at the ground temperature
2005    and surface pressure, level $Nrphys$ refers to the lowest model level and level $Nrphys+1$
2006    refers to the surface.
2007    \\
2008    
2009    
2010    \noindent
2011    { \underline {TG}  Ground Temperature ($deg \hspace{.1cm} K$) }
2012    
2013    \noindent
2014    The ground temperature equation is solved as part of the turbulence package
2015    using a backward implicit time differencing scheme:
2016    \[
2017    {\bf TG} \hspace{.1cm} is \hspace{.1cm} obtained \hspace{.1cm} from: \hspace{.1cm}
2018    C_g\pp{T_g}{t} = R_{sw} - R_{lw} + Q_{ice} - H - LE
2019    \]
2020    
2021    \noindent
2022    where $R_{sw}$ is the net surface downward shortwave radiative flux, $R_{lw}$ is the
2023    net surface upward longwave radiative flux, $Q_{ice}$ is the heat conduction through
2024    sea ice, $H$ is the upward sensible heat flux, $LE$ is the upward latent heat
2025    flux, and $C_g$ is the total heat capacity of the ground.
2026    $C_g$ is obtained by solving a heat diffusion equation
2027    for the penetration of the diurnal cycle into the ground (\cite{black:77}), and is given by:
2028    \[
2029    C_g = \sqrt{ {\lambda C_s \over {2 \omega} } } = \sqrt{(0.386 + 0.536W + 0.15W^2)2x10^{-3}
2030    { 86400. \over {2 \pi} } } \, \, .
2031    \]
2032    \noindent
2033    Here, the thermal conductivity, $\lambda$, is equal to $2x10^{-3}$ ${ly\over{ sec}}
2034    {cm \over {^oK}}$,
2035    the angular velocity of the earth, $\omega$, is written as $86400$ $sec/day$ divided
2036    by $2 \pi$ $radians/
2037    day$, and the expression for $C_s$, the heat capacity per unit volume at the surface,
2038    is a function of the ground wetness, $W$.
2039    \\
2040    
2041    \noindent
2042    { \underline {TS}  Surface Temperature ($deg \hspace{.1cm} K$) }
2043    
2044    \noindent
2045    The surface temperature estimate is made by assuming that the model's lowest
2046    layer is well-mixed, and therefore that $\theta$ is constant in that layer.
2047    The surface temperature is therefore:
2048    \[
2049    {\bf TS} = \theta_{Nrphys} P^{\kappa}_{surf}
2050    \]
2051    \\
2052    
2053    \noindent
2054    { \underline {DTG}  Surface Temperature Adjustment ($deg \hspace{.1cm} K$) }
2055    
2056    \noindent
2057    The change in surface temperature from one turbulence time step to the next, solved
2058    using the Ground Temperature Equation (see diagnostic number 30) is calculated:
2059    \[
2060    {\bf DTG} = {T_g}^{n} - {T_g}^{n-1}
2061    \]
2062    
2063    \noindent
2064    where superscript $n$ refers to the new, updated time level, and the superscript $n-1$
2065    refers to the value at the previous turbulence time level.
2066    \\
2067    
2068    \noindent
2069    { \underline {QG}  Ground Specific Humidity ($g/kg$) }
2070    
2071    \noindent
2072    The ground specific humidity is obtained by interpolating between the specific
2073    humidity at the lowest model level and the specific humidity of a saturated ground.
2074    The interpolation is performed using the potential evapotranspiration function:
2075    \[
2076    {\bf QG} = q_{Nrphys+1} = q_{Nrphys} + \beta(q^*(T_g,P_s) - q_{Nrphys})
2077    \]
2078    
2079    \noindent
2080    where $\beta$ is the surface potential evapotranspiration coefficient ($\beta=1$ over oceans),
2081    and $q^*(T_g,P_s)$ is the saturation specific humidity at the ground temperature and surface
2082    pressure.
2083    \\
2084    
2085    \noindent
2086    { \underline {QS}  Saturation Surface Specific Humidity ($g/kg$) }
2087    
2088    \noindent
2089    The surface saturation specific humidity is the saturation specific humidity at
2090    the ground temprature and surface pressure:
2091    \[
2092    {\bf QS} = q^*(T_g,P_s)
2093    \]
2094    \\
2095    
2096    \noindent
2097    { \underline {TGRLW} Instantaneous ground temperature used as input to the Longwave
2098     radiation subroutine (deg)}
2099    \[
2100    {\bf TGRLW}  = T_g(\lambda , \phi ,n)
2101    \]
2102    \noindent
2103    where $T_g$ is the model ground temperature at the current time step $n$.
2104    \\
2105    
2106    
2107    \noindent
2108    { \underline {ST4} Upward Longwave flux at the surface ($Watts/m^2$) }
2109    \[
2110    {\bf ST4} = \sigma T^4
2111    \]
2112    \noindent
2113    where $\sigma$ is the Stefan-Boltzmann constant and T is the temperature.
2114    \\
2115    
2116    \noindent
2117    { \underline {OLR} Net upward Longwave flux at $p=p_{top}$ ($Watts/m^2$) }
2118    \[
2119    {\bf OLR}  =  F_{LW,top}^{NET}
2120    \]
2121    \noindent
2122    where top indicates the top of the first model layer.
2123    In the GCM, $p_{top}$ = 0.0 mb.
2124    \\
2125    
2126    
2127    \noindent
2128    { \underline {OLRCLR} Net upward clearsky Longwave flux at $p=p_{top}$ ($Watts/m^2$) }
2129    \[
2130    {\bf OLRCLR}  =  F(clearsky)_{LW,top}^{NET}
2131    \]
2132    \noindent
2133    where top indicates the top of the first model layer.
2134    In the GCM, $p_{top}$ = 0.0 mb.
2135    \\
2136    
2137    \noindent
2138    { \underline {LWGCLR} Net upward clearsky Longwave flux at the surface ($Watts/m^2$) }
2139    
2140    \noindent
2141    \begin{eqnarray*}
2142    {\bf LWGCLR} & =  & F(clearsky)_{LW,Nrphys+1}^{Net} \\
2143                 & =  & F(clearsky)_{LW,Nrphys+1}^\uparrow - F(clearsky)_{LW,Nrphys+1}^\downarrow
2144    \end{eqnarray*}
2145    where Nrphys+1 indicates the lowest model edge-level, or $p = p_{surf}$.
2146    $F(clearsky)_{LW}^\uparrow$ is
2147    the upward clearsky Longwave flux and the $F(clearsky)_{LW}^\downarrow$ is the downward clearsky Longwave flux.
2148    \\
2149    
2150    \noindent
2151    { \underline {LWCLR} Heating Rate due to Clearsky Longwave Radiation ($deg/day$) }
2152    
2153    \noindent
2154    The net longwave heating rate is calculated as the vertical divergence of the
2155    net terrestrial radiative fluxes.
2156    Both the clear-sky and cloudy-sky longwave fluxes are computed within the
2157    longwave routine.
2158    The subroutine calculates the clear-sky flux, $F^{clearsky}_{LW}$, first.
2159    For a given cloud fraction,
2160    the clear line-of-sight probability $C(p,p^{\prime})$ is computed from the current level pressure $p$
2161    to the model top pressure, $p^{\prime} = p_{top}$, and the model surface pressure, $p^{\prime} = p_{surf}$,
2162    for the upward and downward radiative fluxes.
2163    (see Section \ref{sec:fizhi:radcloud}).
2164    The cloudy-sky flux is then obtained as:
2165      
2166    \noindent
2167    \[
2168    F_{LW} = C(p,p') \cdot F^{clearsky}_{LW},
2169    \]
2170    
2171    \noindent
2172    Thus, {\bf LWCLR} is defined as the net longwave heating rate due to the
2173    vertical divergence of the
2174    clear-sky longwave radiative flux:
2175    \[
2176    \pp{\rho c_p T}{t}_{clearsky} = - {\partial \over \partial z} F(clearsky)_{LW}^{NET} ,
2177    \]
2178    or
2179    \[
2180    {\bf LWCLR} = \frac{g}{c_p \pi} {\partial \over \partial \sigma} F(clearsky)_{LW}^{NET} .
2181    \]
2182    
2183    \noindent
2184    where $g$ is the accelation due to gravity,
2185    $c_p$ is the heat capacity of air at constant pressure,
2186    and
2187    \[
2188    F(clearsky)_{LW}^{Net} = F(clearsky)_{LW}^\uparrow - F(clearsky)_{LW}^\downarrow
2189    \]
2190    \\
2191    
2192    
2193    \noindent
2194    { \underline {TLW} Instantaneous temperature used as input to the Longwave
2195     radiation subroutine (deg)}
2196    \[
2197    {\bf TLW}  = T(\lambda , \phi ,level, n)
2198    \]
2199    \noindent
2200    where $T$ is the model temperature at the current time step $n$.
2201    \\
2202    
2203    
2204    \noindent
2205    { \underline {SHLW} Instantaneous specific humidity used as input to
2206     the Longwave radiation subroutine (kg/kg)}
2207    \[
2208    {\bf SHLW}  = q(\lambda , \phi , level , n)
2209    \]
2210    \noindent
2211    where $q$ is the model specific humidity at the current time step $n$.
2212    \\
2213    
2214    
2215    \noindent
2216    { \underline {OZLW} Instantaneous ozone used as input to
2217     the Longwave radiation subroutine (kg/kg)}
2218    \[
2219    {\bf OZLW}  = {\rm OZ}(\lambda , \phi , level , n)
2220    \]
2221    \noindent
2222    where $\rm OZ$ is the interpolated ozone data set from the climatological monthly
2223    mean zonally averaged ozone data set.
2224    \\
2225    
2226    
2227    \noindent
2228    { \underline {CLMOLW} Maximum Overlap cloud fraction used in LW Radiation ($0-1$) }
2229    
2230    \noindent
2231    {\bf CLMOLW} is the time-averaged maximum overlap cloud fraction that has been filled by the Relaxed
2232    Arakawa/Schubert Convection scheme and will be used in the Longwave Radiation algorithm.  These are
2233    convective clouds whose radiative characteristics are assumed to be correlated in the vertical.
2234    For a complete description of cloud/radiative interactions, see Section \ref{sec:fizhi:radcloud}.
2235    \[
2236    {\bf CLMOLW} = CLMO_{RAS,LW}(\lambda, \phi,  level )
2237    \]
2238    \\
2239    
2240    
2241    { \underline {CLDTOT} Total cloud fraction used in LW and SW Radiation ($0-1$) }
2242    
2243    {\bf CLDTOT} is the time-averaged total cloud fraction that has been filled by the Relaxed
2244    Arakawa/Schubert and Large-scale Convection schemes and will be used in the Longwave and Shortwave
2245    Radiation packages.
2246    For a complete description of cloud/radiative interactions, see Section \ref{sec:fizhi:radcloud}.
2247    \[
2248    {\bf CLDTOT} = F_{RAS} + F_{LS}
2249    \]
2250    \\
2251    where $F_{RAS}$ is the time-averaged cloud fraction due to sub-grid scale convection, and $F_{LS}$ is the
2252    time-averaged cloud fraction due to precipitating and non-precipitating large-scale moist processes.
2253    \\
2254    
2255    
2256    \noindent
2257    { \underline {CLMOSW} Maximum Overlap cloud fraction used in SW Radiation ($0-1$) }
2258    
2259    \noindent
2260    {\bf CLMOSW} is the time-averaged maximum overlap cloud fraction that has been filled by the Relaxed
2261    Arakawa/Schubert Convection scheme and will be used in the Shortwave Radiation algorithm.  These are
2262    convective clouds whose radiative characteristics are assumed to be correlated in the vertical.
2263    For a complete description of cloud/radiative interactions, see Section \ref{sec:fizhi:radcloud}.
2264    \[
2265    {\bf CLMOSW} = CLMO_{RAS,SW}(\lambda, \phi,  level )
2266    \]
2267    \\
2268    
2269    \noindent
2270    { \underline {CLROSW} Random Overlap cloud fraction used in SW Radiation ($0-1$) }
2271    
2272    \noindent
2273    {\bf CLROSW} is the time-averaged random overlap cloud fraction that has been filled by the Relaxed
2274    Arakawa/Schubert and Large-scale Convection schemes and will be used in the Shortwave
2275    Radiation algorithm.  These are
2276    convective and large-scale clouds whose radiative characteristics are not
2277    assumed to be correlated in the vertical.
2278    For a complete description of cloud/radiative interactions, see Section \ref{sec:fizhi:radcloud}.
2279    \[
2280    {\bf CLROSW} = CLRO_{RAS,Large Scale,SW}(\lambda, \phi,  level )
2281    \]
2282    \\
2283    
2284    \noindent
2285    { \underline {RADSWT} Incident Shortwave radiation at the top of the atmosphere ($Watts/m^2$) }
2286    \[
2287    {\bf RADSWT} = {\frac{S_0}{R_a^2}} \cdot cos \phi_z
2288    \]
2289    \noindent
2290    where $S_0$, is the extra-terrestial solar contant,
2291    $R_a$ is the earth-sun distance in Astronomical Units,
2292    and $cos \phi_z$ is the cosine of the zenith angle.
2293    It should be noted that {\bf RADSWT}, as well as
2294    {\bf OSR} and {\bf OSRCLR},
2295    are calculated at the top of the atmosphere (p=0 mb).  However, the
2296    {\bf OLR} and {\bf OLRCLR} diagnostics are currently
2297    calculated at $p= p_{top}$ (0.0 mb for the GCM).
2298    \\
2299      
2300    \noindent
2301    { \underline {EVAP}  Surface Evaporation ($mm/day$) }
2302    
2303    \noindent
2304    The surface evaporation is a function of the gradient of moisture, the potential
2305    evapotranspiration fraction and the eddy exchange coefficient:
2306    \[
2307    {\bf EVAP} =  \rho \beta K_{h} (q_{surface} - q_{Nrphys})
2308    \]
2309    where $\rho$ = the atmospheric density at the surface, $\beta$ is the fraction of
2310    the potential evapotranspiration actually evaporated ($\beta=1$ over oceans), $K_{h}$ is the
2311    turbulent eddy exchange coefficient for heat and moisture at the surface in $m/sec$ and
2312    $q{surface}$ and $q_{Nrphys}$ are the specific humidity at the surface (see diagnostic
2313    number 34) and at the bottom model level, respectively.
2314    \\
2315    
2316    \noindent
2317    { \underline {DUDT} Total Zonal U-Wind Tendency  ($m/sec/day$) }
2318    
2319    \noindent
2320    {\bf DUDT} is the total time-tendency of the Zonal U-Wind due to Hydrodynamic, Diabatic,
2321    and Analysis forcing.
2322    \[
2323    {\bf DUDT} = \pp{u}{t}_{Dynamics} + \pp{u}{t}_{Moist} + \pp{u}{t}_{Turbulence} + \pp{u}{t}_{Analysis}
2324    \]
2325    \\
2326    
2327    \noindent
2328    { \underline {DVDT} Total Zonal V-Wind Tendency  ($m/sec/day$) }
2329    
2330    \noindent
2331    {\bf DVDT} is the total time-tendency of the Meridional V-Wind due to Hydrodynamic, Diabatic,
2332    and Analysis forcing.
2333    \[
2334    {\bf DVDT} = \pp{v}{t}_{Dynamics} + \pp{v}{t}_{Moist} + \pp{v}{t}_{Turbulence} + \pp{v}{t}_{Analysis}
2335    \]
2336    \\
2337    
2338    \noindent
2339    { \underline {DTDT} Total Temperature Tendency  ($deg/day$) }
2340    
2341    \noindent
2342    {\bf DTDT} is the total time-tendency of Temperature due to Hydrodynamic, Diabatic,
2343    and Analysis forcing.
2344    \begin{eqnarray*}
2345    {\bf DTDT} & = & \pp{T}{t}_{Dynamics} + \pp{T}{t}_{Moist Processes} + \pp{T}{t}_{Shortwave Radiation} \\
2346               & + & \pp{T}{t}_{Longwave Radiation} + \pp{T}{t}_{Turbulence} + \pp{T}{t}_{Analysis}
2347    \end{eqnarray*}
2348    \\
2349    
2350    \noindent
2351    { \underline {DQDT} Total Specific Humidity Tendency  ($g/kg/day$) }
2352    
2353    \noindent
2354    {\bf DQDT} is the total time-tendency of Specific Humidity due to Hydrodynamic, Diabatic,
2355    and Analysis forcing.
2356    \[
2357    {\bf DQDT} = \pp{q}{t}_{Dynamics} + \pp{q}{t}_{Moist Processes}
2358    + \pp{q}{t}_{Turbulence} + \pp{q}{t}_{Analysis}
2359    \]
2360    \\
2361      
2362    \noindent
2363    { \underline {USTAR}  Surface-Stress Velocity ($m/sec$) }
2364    
2365    \noindent
2366    The surface stress velocity, or the friction velocity, is the wind speed at
2367    the surface layer top impeded by the surface drag:
2368    \[
2369    {\bf USTAR} = C_uW_s \hspace{1cm}where: \hspace{.2cm}
2370    C_u = {k \over {\psi_m} }
2371    \]
2372    
2373    \noindent
2374    $C_u$ is the non-dimensional surface drag coefficient (see diagnostic
2375    number 10), and $W_s$ is the surface wind speed (see diagnostic number 28).
2376    
2377    \noindent
2378    { \underline {Z0}  Surface Roughness Length ($m$) }
2379    
2380    \noindent
2381    Over the land surface, the surface roughness length is interpolated to the local
2382    time from the monthly mean data of \cite{dorsell:89}. Over the ocean,
2383    the roughness length is a function of the surface-stress velocity, $u_*$.
2384    \[
2385    {\bf Z0} = c_1u^3_* + c_2u^2_* + c_3u_* + c_4 + {c_5 \over {u_*}}
2386    \]
2387    
2388    \noindent
2389    where the constants are chosen to interpolate between the reciprocal relation of
2390    \cite{kondo:75} for weak winds, and the piecewise linear relation of \cite{larpond:81}
2391    for moderate to large winds.
2392    \\
2393    
2394    \noindent
2395    { \underline {FRQTRB}  Frequency of Turbulence ($0-1$) }
2396    
2397    \noindent
2398    The fraction of time when turbulence is present is defined as the fraction of
2399    time when the turbulent kinetic energy exceeds some minimum value, defined here
2400    to be $0.005 \hspace{.1cm}m^2/sec^2$. When this criterion is met, a counter is
2401    incremented. The fraction over the averaging interval is reported.
2402    \\
2403    
2404    \noindent
2405    { \underline {PBL}  Planetary Boundary Layer Depth ($mb$) }
2406    
2407    \noindent
2408    The depth of the PBL is defined by the turbulence parameterization to be the
2409    depth at which the turbulent kinetic energy reduces to ten percent of its surface
2410    value.
2411    
2412    \[
2413    {\bf PBL} = P_{PBL} - P_{surface}
2414    \]
2415    
2416    \noindent
2417    where $P_{PBL}$ is the pressure in $mb$ at which the turbulent kinetic energy
2418    reaches one tenth of its surface value, and $P_s$ is the surface pressure.
2419    \\
2420    
2421    \noindent
2422    { \underline {SWCLR} Clear sky Heating Rate due to Shortwave Radiation ($deg/day$) }
2423    
2424    \noindent
2425    The net Shortwave heating rate is calculated as the vertical divergence of the
2426    net solar radiative fluxes.
2427    The clear-sky and cloudy-sky shortwave fluxes are calculated separately.
2428    For the clear-sky case, the shortwave fluxes and heating rates are computed with
2429    both CLMO (maximum overlap cloud fraction) and
2430    CLRO (random overlap cloud fraction) set to zero (see Section \ref{sec:fizhi:radcloud}).
2431    The shortwave routine is then called a second time, for the cloudy-sky case, with the
2432    true time-averaged cloud fractions CLMO
2433    and CLRO being used.  In all cases, a normalized incident shortwave flux is used as
2434    input at the top of the atmosphere.
2435    
2436    \noindent
2437    The heating rate due to Shortwave Radiation under clear skies is defined as:
2438    \[
2439    \pp{\rho c_p T}{t} = - {\partial \over \partial z} F(clear)_{SW}^{NET} \cdot {\rm RADSWT},
2440    \]
2441    or
2442    \[
2443    {\bf SWCLR} = \frac{g}{c_p } {\partial \over \partial p} F(clear)_{SW}^{NET}\cdot {\rm RADSWT} .
2444    \]
2445    
2446    \noindent
2447    where $g$ is the accelation due to gravity,
2448    $c_p$ is the heat capacity of air at constant pressure, RADSWT is the true incident
2449    shortwave radiation at the top of the atmosphere (See Diagnostic \#48), and
2450    \[
2451    F(clear)_{SW}^{Net} = F(clear)_{SW}^\uparrow - F(clear)_{SW}^\downarrow
2452    \]
2453    \\
2454    
2455    \noindent
2456    { \underline {OSR} Net upward Shortwave flux at the top of the model ($Watts/m^2$) }
2457    \[
2458    {\bf OSR}  =  F_{SW,top}^{NET}
2459    \]                                                                                      
2460    \noindent
2461    where top indicates the top of the first model layer used in the shortwave radiation
2462    routine.
2463    In the GCM, $p_{SW_{top}}$ = 0 mb.
2464    \\
2465    
2466    \noindent
2467    { \underline {OSRCLR} Net upward clearsky Shortwave flux at the top of the model ($Watts/m^2$) }
2468    \[
2469    {\bf OSRCLR}  =  F(clearsky)_{SW,top}^{NET}
2470    \]
2471    \noindent
2472    where top indicates the top of the first model layer used in the shortwave radiation
2473    routine.
2474    In the GCM, $p_{SW_{top}}$ = 0 mb.
2475    \\
2476    
2477    
2478    \noindent
2479    { \underline {CLDMAS} Convective Cloud Mass Flux ($kg/m^2$) }
2480    
2481    \noindent
2482    The amount of cloud mass moved per RAS timestep from all convective clouds is written:
2483    \[
2484    {\bf CLDMAS} = \eta m_B
2485    \]
2486    where $\eta$ is the entrainment, normalized by the cloud base mass flux, and $m_B$ is
2487    the cloud base mass flux. $m_B$ and $\eta$ are defined explicitly in Section \ref{sec:fizhi:mc}, the
2488    description of the convective parameterization.
2489    \\
2490    
2491    
2492    
2493    \noindent
2494    { \underline {UAVE} Time-Averaged Zonal U-Wind ($m/sec$) }
2495    
2496    \noindent
2497    The diagnostic {\bf UAVE} is simply the time-averaged Zonal U-Wind over
2498    the {\bf NUAVE} output frequency.  This is contrasted to the instantaneous
2499    Zonal U-Wind which is archived on the Prognostic Output data stream.
2500    \[
2501    {\bf UAVE} = u(\lambda, \phi, level , t)
2502    \]
2503    \\
2504    Note, {\bf UAVE} is computed and stored on the staggered C-grid.
2505    \\
2506    
2507    \noindent
2508    { \underline {VAVE} Time-Averaged Meridional V-Wind ($m/sec$) }
2509    
2510    \noindent
2511    The diagnostic {\bf VAVE} is simply the time-averaged Meridional V-Wind over
2512    the {\bf NVAVE} output frequency.  This is contrasted to the instantaneous
2513    Meridional V-Wind which is archived on the Prognostic Output data stream.
2514    \[
2515    {\bf VAVE} = v(\lambda, \phi, level , t)
2516    \]
2517    \\
2518    Note, {\bf VAVE} is computed and stored on the staggered C-grid.
2519    \\
2520    
2521    \noindent
2522    { \underline {TAVE} Time-Averaged Temperature ($Kelvin$) }
2523    
2524    \noindent
2525    The diagnostic {\bf TAVE} is simply the time-averaged Temperature over
2526    the {\bf NTAVE} output frequency.  This is contrasted to the instantaneous
2527    Temperature which is archived on the Prognostic Output data stream.
2528    \[
2529    {\bf TAVE} = T(\lambda, \phi, level , t)
2530    \]
2531    \\
2532    
2533    \noindent
2534    { \underline {QAVE} Time-Averaged Specific Humidity ($g/kg$) }
2535    
2536    \noindent
2537    The diagnostic {\bf QAVE} is simply the time-averaged Specific Humidity over
2538    the {\bf NQAVE} output frequency.  This is contrasted to the instantaneous
2539    Specific Humidity which is archived on the Prognostic Output data stream.
2540    \[
2541    {\bf QAVE} = q(\lambda, \phi, level , t)
2542    \]
2543    \\
2544    
2545    \noindent
2546    { \underline {PAVE} Time-Averaged Surface Pressure - PTOP ($mb$) }
2547    
2548    \noindent
2549    The diagnostic {\bf PAVE} is simply the time-averaged Surface Pressure - PTOP over
2550    the {\bf NPAVE} output frequency.  This is contrasted to the instantaneous
2551    Surface Pressure - PTOP which is archived on the Prognostic Output data stream.
2552    \begin{eqnarray*}
2553    {\bf PAVE} & =  & \pi(\lambda, \phi, level , t) \\
2554               & =  & p_s(\lambda, \phi, level , t) - p_T
2555    \end{eqnarray*}
2556    \\
2557    
2558    
2559    \noindent
2560    { \underline {QQAVE} Time-Averaged Turbulent Kinetic Energy $(m/sec)^2$ }
2561    
2562    \noindent
2563    The diagnostic {\bf QQAVE} is simply the time-averaged prognostic Turbulent Kinetic Energy
2564    produced by the GCM Turbulence parameterization over
2565    the {\bf NQQAVE} output frequency.  This is contrasted to the instantaneous
2566    Turbulent Kinetic Energy which is archived on the Prognostic Output data stream.
2567    \[
2568    {\bf QQAVE} = qq(\lambda, \phi, level , t)
2569    \]
2570    \\
2571    Note, {\bf QQAVE} is computed and stored at the ``mass-point'' locations on the staggered C-grid.
2572    \\
2573    
2574    \noindent
2575    { \underline {SWGCLR} Net downward clearsky Shortwave flux at the surface ($Watts/m^2$) }
2576    
2577    \noindent
2578    \begin{eqnarray*}
2579    {\bf SWGCLR} & =  & F(clearsky)_{SW,Nrphys+1}^{Net} \\
2580                 & =  & F(clearsky)_{SW,Nrphys+1}^\downarrow - F(clearsky)_{SW,Nrphys+1}^\uparrow
2581    \end{eqnarray*}
2582    \noindent
2583    \\
2584    where Nrphys+1 indicates the lowest model edge-level, or $p = p_{surf}$.
2585    $F(clearsky){SW}^\downarrow$ is
2586    the downward clearsky Shortwave flux and $F(clearsky)_{SW}^\uparrow$ is
2587    the upward clearsky Shortwave flux.
2588    \\
2589    
2590    \noindent
2591    { \underline {DIABU} Total Diabatic Zonal U-Wind Tendency  ($m/sec/day$) }
2592    
2593    \noindent
2594    {\bf DIABU} is the total time-tendency of the Zonal U-Wind due to Diabatic processes
2595    and the Analysis forcing.
2596    \[
2597    {\bf DIABU} = \pp{u}{t}_{Moist} + \pp{u}{t}_{Turbulence} + \pp{u}{t}_{Analysis}
2598    \]
2599    \\
2600    
2601    \noindent
2602    { \underline {DIABV} Total Diabatic Meridional V-Wind Tendency  ($m/sec/day$) }
2603    
2604    \noindent
2605    {\bf DIABV} is the total time-tendency of the Meridional V-Wind due to Diabatic processes
2606    and the Analysis forcing.
2607    \[
2608    {\bf DIABV} = \pp{v}{t}_{Moist} + \pp{v}{t}_{Turbulence} + \pp{v}{t}_{Analysis}
2609    \]
2610    \\
2611    
2612    \noindent
2613    { \underline {DIABT} Total Diabatic Temperature Tendency  ($deg/day$) }
2614    
2615    \noindent
2616    {\bf DIABT} is the total time-tendency of Temperature due to Diabatic processes
2617    and the Analysis forcing.
2618    \begin{eqnarray*}
2619    {\bf DIABT} & = & \pp{T}{t}_{Moist Processes} + \pp{T}{t}_{Shortwave Radiation} \\
2620               & + & \pp{T}{t}_{Longwave Radiation} + \pp{T}{t}_{Turbulence} + \pp{T}{t}_{Analysis}
2621    \end{eqnarray*}
2622    \\
2623    If we define the time-tendency of Temperature due to Diabatic processes as
2624    \begin{eqnarray*}
2625    \pp{T}{t}_{Diabatic} & = & \pp{T}{t}_{Moist Processes} + \pp{T}{t}_{Shortwave Radiation} \\
2626                         & + & \pp{T}{t}_{Longwave Radiation} + \pp{T}{t}_{Turbulence}
2627    \end{eqnarray*}
2628    then, since there are no surface pressure changes due to Diabatic processes, we may write
2629    \[
2630    \pp{T}{t}_{Diabatic} = {p^\kappa \over \pi }\pp{\pi \theta}{t}_{Diabatic}
2631    \]
2632    where $\theta = T/p^\kappa$.  Thus, {\bf DIABT} may be written as
2633    \[
2634    {\bf DIABT} = {p^\kappa \over \pi } \left( \pp{\pi \theta}{t}_{Diabatic} + \pp{\pi \theta}{t}_{Analysis} \right)
2635    \]
2636    \\
2637    
2638    \noindent
2639    { \underline {DIABQ} Total Diabatic Specific Humidity Tendency  ($g/kg/day$) }
2640    
2641    \noindent
2642    {\bf DIABQ} is the total time-tendency of Specific Humidity due to Diabatic processes
2643    and the Analysis forcing.
2644    \[
2645    {\bf DIABQ} = \pp{q}{t}_{Moist Processes} + \pp{q}{t}_{Turbulence} + \pp{q}{t}_{Analysis}
2646    \]
2647    If we define the time-tendency of Specific Humidity due to Diabatic processes as
2648    \[
2649    \pp{q}{t}_{Diabatic} = \pp{q}{t}_{Moist Processes} + \pp{q}{t}_{Turbulence}
2650    \]
2651    then, since there are no surface pressure changes due to Diabatic processes, we may write
2652    \[
2653    \pp{q}{t}_{Diabatic} = {1 \over \pi }\pp{\pi q}{t}_{Diabatic}
2654    \]
2655    Thus, {\bf DIABQ} may be written as
2656    \[
2657    {\bf DIABQ} = {1 \over \pi } \left( \pp{\pi q}{t}_{Diabatic} + \pp{\pi q}{t}_{Analysis} \right)
2658    \]
2659    \\
2660    
2661    \noindent
2662    { \underline {VINTUQ} Vertically Integrated Moisture Flux ($m/sec \cdot g/kg$) }
2663    
2664    \noindent
2665    The vertically integrated moisture flux due to the zonal u-wind is obtained by integrating
2666    $u q$ over the depth of the atmosphere at each model timestep,
2667    and dividing by the total mass of the column.
2668    \[
2669    {\bf VINTUQ} = \frac{ \int_{surf}^{top} u q \rho dz  } { \int_{surf}^{top} \rho dz  }
2670    \]
2671    Using $\rho \delta z = -{\delta p \over g} = - {1 \over g} \delta p$, we have
2672    \[
2673    {\bf VINTUQ} = { \int_0^1 u q dp  }
2674    \]
2675    \\
2676    
2677    
2678    \noindent
2679    { \underline {VINTVQ} Vertically Integrated Moisture Flux ($m/sec \cdot g/kg$) }
2680    
2681    \noindent
2682    The vertically integrated moisture flux due to the meridional v-wind is obtained by integrating
2683    $v q$ over the depth of the atmosphere at each model timestep,
2684    and dividing by the total mass of the column.
2685    \[
2686    {\bf VINTVQ} = \frac{ \int_{surf}^{top} v q \rho dz  } { \int_{surf}^{top} \rho dz  }
2687    \]
2688    Using $\rho \delta z = -{\delta p \over g} = - {1 \over g} \delta p$, we have
2689    \[
2690    {\bf VINTVQ} = { \int_0^1 v q dp  }
2691    \]
2692    \\
2693    
2694    
2695    \noindent
2696    { \underline {VINTUT} Vertically Integrated Heat Flux ($m/sec \cdot deg$) }
2697    
2698    \noindent
2699    The vertically integrated heat flux due to the zonal u-wind is obtained by integrating
2700    $u T$ over the depth of the atmosphere at each model timestep,
2701    and dividing by the total mass of the column.
2702    \[
2703    {\bf VINTUT} = \frac{ \int_{surf}^{top} u T \rho dz  } { \int_{surf}^{top} \rho dz  }
2704    \]
2705    Or,
2706    \[
2707    {\bf VINTUT} = { \int_0^1 u T dp  }
2708    \]
2709    \\
2710    
2711    \noindent
2712    { \underline {VINTVT} Vertically Integrated Heat Flux ($m/sec \cdot deg$) }
2713    
2714    \noindent
2715    The vertically integrated heat flux due to the meridional v-wind is obtained by integrating
2716    $v T$ over the depth of the atmosphere at each model timestep,
2717    and dividing by the total mass of the column.
2718    \[
2719    {\bf VINTVT} = \frac{ \int_{surf}^{top} v T \rho dz  } { \int_{surf}^{top} \rho dz  }
2720    \]
2721    Using $\rho \delta z = -{\delta p \over g} $, we have
2722    \[
2723    {\bf VINTVT} = { \int_0^1 v T dp  }
2724    \]
2725    \\
2726    
2727    \noindent
2728    { \underline {CLDFRC} Total 2-Dimensional Cloud Fracton ($0-1$) }
2729    
2730    If we define the
2731    time-averaged random and maximum overlapped cloudiness as CLRO and
2732    CLMO respectively, then the probability of clear sky associated
2733    with random overlapped clouds at any level is (1-CLRO) while the probability of
2734    clear sky associated with maximum overlapped clouds at any level is (1-CLMO).
2735    The total clear sky probability is given by (1-CLRO)*(1-CLMO), thus
2736    the total cloud fraction at each  level may be obtained by
2737    1-(1-CLRO)*(1-CLMO).
2738    
2739    At any given level, we may define the clear line-of-site probability by
2740    appropriately accounting for the maximum and random overlap
2741    cloudiness.  The clear line-of-site probability is defined to be
2742    equal to the product of the clear line-of-site probabilities
2743    associated with random and maximum overlap cloudiness.  The clear
2744    line-of-site probability $C(p,p^{\prime})$ associated with maximum overlap clouds,
2745    from the current pressure $p$
2746    to the model top pressure, $p^{\prime} = p_{top}$, or the model surface pressure, $p^{\prime} = p_{surf}$,
2747    is simply 1.0 minus the largest maximum overlap cloud value along  the
2748    line-of-site, ie.
2749    
2750    $$1-MAX_p^{p^{\prime}} \left( CLMO_p \right)$$
2751    
2752    Thus, even in the time-averaged sense it is assumed that the
2753    maximum overlap clouds are correlated in the vertical.  The clear
2754    line-of-site probability associated with random overlap clouds is
2755    defined to be the product of the clear sky probabilities at each
2756    level along the line-of-site, ie.
2757    
2758    $$\prod_{p}^{p^{\prime}} \left( 1-CLRO_p \right)$$
2759    
2760    The total cloud fraction at a given level associated with a line-
2761    of-site calculation is given by
2762    
2763    $$1-\left( 1-MAX_p^{p^{\prime}} \left[ CLMO_p \right] \right)
2764        \prod_p^{p^{\prime}} \left( 1-CLRO_p \right)$$
2765    
2766    
2767    \noindent
2768    The 2-dimensional net cloud fraction as seen from the top of the
2769    atmosphere is given by
2770    \[
2771    {\bf CLDFRC} = 1-\left( 1-MAX_{l=l_1}^{Nrphys} \left[ CLMO_l \right] \right)
2772        \prod_{l=l_1}^{Nrphys} \left( 1-CLRO_l \right)
2773    \]
2774    \\
2775    For a complete description of cloud/radiative interactions, see Section \ref{sec:fizhi:radcloud}.
2776    
2777    
2778    \noindent
2779    { \underline {QINT} Total Precipitable Water ($gm/cm^2$) }
2780    
2781    \noindent
2782    The Total Precipitable Water is defined as the vertical integral of the specific humidity,
2783    given by:
2784    \begin{eqnarray*}
2785    {\bf QINT} & = & \int_{surf}^{top} \rho q dz \\
2786               & = & {\pi \over g} \int_0^1 q dp
2787    \end{eqnarray*}
2788    where we have used the hydrostatic relation
2789    $\rho \delta z = -{\delta p \over g} $.
2790    \\
2791    
2792    
2793    \noindent
2794    { \underline {U2M}  Zonal U-Wind at 2 Meter Depth ($m/sec$) }
2795    
2796    \noindent
2797    The u-wind at the 2-meter depth is determined from the similarity theory:
2798    \[
2799    {\bf U2M} = {u_* \over k} \psi_{m_{2m}} {u_{sl} \over {W_s}} =
2800    { \psi_{m_{2m}} \over {\psi_{m_{sl}} }}u_{sl}
2801    \]
2802    
2803    \noindent
2804    where $\psi_m(2m)$ is the non-dimensional wind shear at two meters, and the subscript
2805    $sl$ refers to the height of the top of the surface layer. If the roughness height
2806    is above two meters, ${\bf U2M}$ is undefined.
2807    \\
2808    
2809    \noindent
2810    { \underline {V2M}  Meridional V-Wind at 2 Meter Depth ($m/sec$) }
2811    
2812    \noindent
2813    The v-wind at the 2-meter depth is a determined from the similarity theory:
2814    \[
2815    {\bf V2M} = {u_* \over k} \psi_{m_{2m}} {v_{sl} \over {W_s}} =
2816    { \psi_{m_{2m}} \over {\psi_{m_{sl}} }}v_{sl}
2817    \]
2818    
2819    \noindent
2820    where $\psi_m(2m)$ is the non-dimensional wind shear at two meters, and the subscript
2821    $sl$ refers to the height of the top of the surface layer. If the roughness height
2822    is above two meters, ${\bf V2M}$ is undefined.
2823    \\
2824    
2825    \noindent
2826    { \underline {T2M}  Temperature at 2 Meter Depth ($deg \hspace{.1cm} K$) }
2827    
2828    \noindent
2829    The temperature at the 2-meter depth is a determined from the similarity theory:
2830    \[
2831    {\bf T2M} = P^{\kappa} ({\theta* \over k} ({\psi_{h_{2m}}+\psi_g}) + \theta_{surf} ) =
2832    P^{\kappa}(\theta_{surf} + { {\psi_{h_{2m}}+\psi_g} \over {{\psi_{h_{sl}}+\psi_g}} }
2833    (\theta_{sl} - \theta_{surf}))
2834    \]
2835    where:
2836    \[
2837    \theta_* = - { (\overline{w^{\prime}\theta^{\prime}}) \over {u_*} }
2838    \]
2839    
2840    \noindent
2841    where $\psi_h(2m)$ is the non-dimensional temperature gradient at two meters, $\psi_g$ is
2842    the non-dimensional temperature gradient in the viscous sublayer, and the subscript
2843    $sl$ refers to the height of the top of the surface layer. If the roughness height
2844    is above two meters, ${\bf T2M}$ is undefined.
2845    \\
2846    
2847    \noindent
2848    { \underline {Q2M}  Specific Humidity at 2 Meter Depth ($g/kg$) }
2849    
2850    \noindent
2851    The specific humidity at the 2-meter depth is determined from the similarity theory:
2852    \[
2853    {\bf Q2M} = P^{\kappa} ({q_* \over k} ({\psi_{h_{2m}}+\psi_g}) + q_{surf} ) =
2854    P^{\kappa}(q_{surf} + { {\psi_{h_{2m}}+\psi_g} \over {{\psi_{h_{sl}}+\psi_g}} }
2855    (q_{sl} - q_{surf}))
2856    \]
2857    where:
2858    \[
2859    q_* = - { (\overline{w^{\prime}q^{\prime}}) \over {u_*} }
2860    \]
2861    
2862    \noindent
2863    where $\psi_h(2m)$ is the non-dimensional temperature gradient at two meters, $\psi_g$ is
2864    the non-dimensional temperature gradient in the viscous sublayer, and the subscript
2865    $sl$ refers to the height of the top of the surface layer. If the roughness height
2866    is above two meters, ${\bf Q2M}$ is undefined.
2867    \\
2868    
2869    \noindent
2870    { \underline {U10M}  Zonal U-Wind at 10 Meter Depth ($m/sec$) }
2871    
2872    \noindent
2873    The u-wind at the 10-meter depth is an interpolation between the surface wind
2874    and the model lowest level wind using the ratio of the non-dimensional wind shear
2875    at the two levels:
2876    \[
2877    {\bf U10M} = {u_* \over k} \psi_{m_{10m}} {u_{sl} \over {W_s}} =
2878    { \psi_{m_{10m}} \over {\psi_{m_{sl}} }}u_{sl}
2879    \]
2880    
2881    \noindent
2882    where $\psi_m(10m)$ is the non-dimensional wind shear at ten meters, and the subscript
2883    $sl$ refers to the height of the top of the surface layer.
2884    \\
2885    
2886    \noindent
2887    { \underline {V10M}  Meridional V-Wind at 10 Meter Depth ($m/sec$) }
2888    
2889    \noindent
2890    The v-wind at the 10-meter depth is an interpolation between the surface wind
2891    and the model lowest level wind using the ratio of the non-dimensional wind shear
2892    at the two levels:
2893    \[
2894    {\bf V10M} = {u_* \over k} \psi_{m_{10m}} {v_{sl} \over {W_s}} =
2895    { \psi_{m_{10m}} \over {\psi_{m_{sl}} }}v_{sl}
2896    \]
2897    
2898    \noindent
2899    where $\psi_m(10m)$ is the non-dimensional wind shear at ten meters, and the subscript
2900    $sl$ refers to the height of the top of the surface layer.
2901    \\
2902    
2903    \noindent
2904    { \underline {T10M}  Temperature at 10 Meter Depth ($deg \hspace{.1cm} K$) }
2905    
2906    \noindent
2907    The temperature at the 10-meter depth is an interpolation between the surface potential
2908    temperature and the model lowest level potential temperature using the ratio of the
2909    non-dimensional temperature gradient at the two levels:
2910    \[
2911    {\bf T10M} = P^{\kappa} ({\theta* \over k} ({\psi_{h_{10m}}+\psi_g}) + \theta_{surf} ) =
2912    P^{\kappa}(\theta_{surf} + { {\psi_{h_{10m}}+\psi_g} \over {{\psi_{h_{sl}}+\psi_g}} }
2913    (\theta_{sl} - \theta_{surf}))
2914    \]
2915    where:
2916    \[
2917    \theta_* = - { (\overline{w^{\prime}\theta^{\prime}}) \over {u_*} }
2918    \]
2919    
2920    \noindent
2921    where $\psi_h(10m)$ is the non-dimensional temperature gradient at two meters, $\psi_g$ is
2922    the non-dimensional temperature gradient in the viscous sublayer, and the subscript
2923    $sl$ refers to the height of the top of the surface layer.
2924    \\
2925    
2926    \noindent
2927    { \underline {Q10M}  Specific Humidity at 10 Meter Depth ($g/kg$) }
2928    
2929    \noindent
2930    The specific humidity at the 10-meter depth is an interpolation between the surface specific
2931    humidity and the model lowest level specific humidity using the ratio of the
2932    non-dimensional temperature gradient at the two levels:
2933    \[
2934    {\bf Q10M} = P^{\kappa} ({q_* \over k} ({\psi_{h_{10m}}+\psi_g}) + q_{surf} ) =
2935    P^{\kappa}(q_{surf} + { {\psi_{h_{10m}}+\psi_g} \over {{\psi_{h_{sl}}+\psi_g}} }
2936    (q_{sl} - q_{surf}))
2937    \]
2938    where:
2939    \[
2940    q_* =  - { (\overline{w^{\prime}q^{\prime}}) \over {u_*} }
2941    \]
2942    
2943    \noindent
2944    where $\psi_h(10m)$ is the non-dimensional temperature gradient at two meters, $\psi_g$ is
2945    the non-dimensional temperature gradient in the viscous sublayer, and the subscript
2946    $sl$ refers to the height of the top of the surface layer.
2947    \\
2948    
2949    \noindent
2950    { \underline {DTRAIN} Cloud Detrainment Mass Flux ($kg/m^2$) }
2951    
2952    The amount of cloud mass moved per RAS timestep at the cloud detrainment level is written:
2953    \[
2954    {\bf DTRAIN} = \eta_{r_D}m_B
2955    \]
2956    \noindent
2957    where $r_D$ is the detrainment level,
2958    $m_B$ is the cloud base mass flux, and $\eta$
2959    is the entrainment, defined in Section \ref{sec:fizhi:mc}.
2960    \\
2961    
2962    \noindent
2963    { \underline {QFILL}  Filling of negative Specific Humidity ($g/kg/day$) }
2964    
2965    \noindent
2966    Due to computational errors associated with the numerical scheme used for
2967    the advection of moisture, negative values of specific humidity may be generated.  The
2968    specific humidity is checked for negative values after every dynamics timestep.  If negative
2969    values have been produced, a filling algorithm is invoked which redistributes moisture from
2970    below.  Diagnostic {\bf QFILL} is equal to the net filling needed
2971    to eliminate negative specific humidity, scaled to a per-day rate:
2972    \[
2973    {\bf QFILL} = q^{n+1}_{final} - q^{n+1}_{initial}
2974    \]
2975    where
2976    \[
2977    q^{n+1} = (\pi q)^{n+1} / \pi^{n+1}
2978    \]
2979    
2980    
2981    \subsubsection{Key subroutines, parameters and files}
2982    
2983    \subsubsection{Dos and donts}
2984    
2985  \subsection{Fizhi Reference}  \subsubsection{Fizhi Reference}

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