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revision 1.9 by molod, Mon Jul 18 20:45:27 2005 UTC revision 1.17 by molod, Wed Jun 28 15:35:07 2006 UTC
# Line 8  Line 8 
8  \subsubsection{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  % *************************************************************************  % *************************************************************************
# Line 21  Moist Convective Processes: Line 24  Moist Convective Processes:
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 166  RH_{min} & = & 0.75 \nonumber \\ Line 169  RH_{min} & = & 0.75 \nonumber \\
169    
170  These cloud fractions are suppressed, however, in regions where the convective  These cloud fractions are suppressed, however, in regions where the convective
171  sub-cloud layer is conditionally unstable.  The functional form of $RH_c$ is shown in  sub-cloud layer is conditionally unstable.  The functional form of $RH_c$ is shown in
172  Figure (\ref{fig:fizhi:rhcrit}).  Figure (\ref{fig.rhcrit}).
173    
174  \begin{figure*}[htbp]  \begin{figure*}[htbp]
175    \vspace{0.4in}    \vspace{0.4in}
176    \centerline{  \epsfysize=4.0in  \epsfbox{part6/rhcrit.ps}}    \centerline{  \epsfysize=4.0in  \epsfbox{part6/rhcrit.ps}}
177    \vspace{0.4in}    \vspace{0.4in}
178    \caption  [Critical Relative Humidity for Clouds.]    \caption  [Critical Relative Humidity for Clouds.]
179              {Critical Relative Humidity for Clouds.}              {Critical Relative Humidity for Clouds.}
180    \label{fig:fizhi:rhcrit}    \label{fig.rhcrit}
181  \end{figure*}  \end{figure*}
182    
183  The total cloud fraction in a grid box is determined by the larger of the two cloud fractions:  The total cloud fraction in a grid box is determined by the larger of the two cloud fractions:
# Line 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 305  cloud cover of all the layers in the gro Line 308  cloud cover of all the layers in the gro
308  of a given layer is then scaled for both the direct (as a function of the  of a given layer is then scaled for both the direct (as a function of the
309  solar zenith angle) and diffuse beam radiation  solar zenith angle) and diffuse beam radiation
310  so that the grouped layer reflectance is the same as the original reflectance.  so that the grouped layer reflectance is the same as the original reflectance.
311  The solar flux is computed for each of the eight cloud realizations possible  The solar flux is computed for each of eight cloud realizations possible within this
 (see Figure \ref{fig:fizhi:cloud}) within this  
312  low/middle/high classification, and appropriately averaged to produce the net solar flux.  low/middle/high classification, and appropriately averaged to produce the net solar flux.
313    
 \begin{figure*}[htbp]  
   \vspace{0.4in}  
   \centerline{  \epsfysize=4.0in  %\epsfbox{part6/rhcrit.ps}  
              }  
   \vspace{0.4in}  
   \caption  {Low-Middle-High Cloud Configurations}  
   \label{fig:fizhi:cloud}  
 \end{figure*}  
   
   
314  \paragraph{Longwave Radiation}  \paragraph{Longwave Radiation}
315    
316  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}.
317  As described in that document, IR fluxes are computed due to absorption by water vapor, carbon  As described in that document, IR fluxes are computed due to absorption by water vapor, carbon
318  dioxide, and ozone.  The spectral bands together with their absorbers and parameterization methods,  dioxide, and ozone.  The spectral bands together with their absorbers and parameterization methods,
319  configured for the fizhi package, are shown in Table \ref{tab:fizhi:longwave}.  configured for the fizhi package, are shown in Table \ref{tab:fizhi:longwave}.
# Line 357  Band & Spectral Range (cm$^{-1}$) & Abso Line 349  Band & Spectral Range (cm$^{-1}$) & Abso
349  \end{tabular}  \end{tabular}
350  \end{center}  \end{center}
351  \vspace{0.1in}  \vspace{0.1in}
352  \caption{IR Spectral Bands, Absorbers, and Parameterization Method (from Chou and Suarez, 1994)}  \caption{IR Spectral Bands, Absorbers, and Parameterization Method (from \cite{chsz:94})}
353  \label{tab:fizhi:longwave}  \label{tab:fizhi:longwave}
354  \end{table}  \end{table}
355    
# Line 428  The cloud fraction values are time-avera Line 420  The cloud fraction values are time-avera
420  hours).  Therefore, in a time-averaged sense, both convective and large-scale  hours).  Therefore, in a time-averaged sense, both convective and large-scale
421  cloudiness can exist in a given grid-box.    cloudiness can exist in a given grid-box.  
422    
423  Turbulence:  \paragraph{Turbulence}:
424    
425  Turbulence is parameterized in the fizhi package to account for its contribution to the  Turbulence is parameterized in the fizhi package to account for its contribution to the
426  vertical exchange of heat, moisture, and momentum.    vertical exchange of heat, moisture, and momentum.  
# Line 459  Within the atmosphere, the time evolutio Line 451  Within the atmosphere, the time evolutio
451  of second turbulent moments is explicitly modeled by representing the third moments in terms of  of second turbulent moments is explicitly modeled by representing the third moments in terms of
452  the first and second moments.  This approach is known as a second-order closure modeling.  the first and second moments.  This approach is known as a second-order closure modeling.
453  To simplify and streamline the computation of the second moments, the level 2.5 assumption  To simplify and streamline the computation of the second moments, the level 2.5 assumption
454  of Mellor and Yamada (1974) and Yamada (1977) is employed, in which only the turbulent  of Mellor and Yamada (1974) and \cite{yam:77} is employed, in which only the turbulent
455  kinetic energy (TKE),  kinetic energy (TKE),
456    
457  \[ {\h}{q^2}={\overline{{u^{\prime}}^2}}+{\overline{{v^{\prime}}^2}}+{\overline{{w^{\prime}}^2}}, \]  \[ {\h}{q^2}={\overline{{u^{\prime}}^2}}+{\overline{{v^{\prime}}^2}}+{\overline{{w^{\prime}}^2}}, \]
# Line 493  of TKE. Line 485  of TKE.
485    
486  In the level 2.5 approach, the vertical fluxes of the scalars $\theta_v$ and $q$ and the  In the level 2.5 approach, the vertical fluxes of the scalars $\theta_v$ and $q$ and the
487  wind components $u$ and $v$ are expressed in terms of the diffusion coefficients $K_h$ and  wind components $u$ and $v$ are expressed in terms of the diffusion coefficients $K_h$ and
488  $K_m$, respectively.  In the statisically realizable level 2.5 turbulence scheme of Helfand  $K_m$, respectively.  In the statisically realizable level 2.5 turbulence scheme of
489  and Labraga (1988), these diffusion coefficients are expressed as  \cite{helflab:88}, these diffusion coefficients are expressed as
490    
491  \[  \[
492  K_h  K_h
# Line 569  where $\psi_h$ is the surface layer non- Line 561  where $\psi_h$ is the surface layer non-
561  \]  \]
562  Here $\phi_h$ is the similarity function of $\zeta$, which expresses the stability dependance of  Here $\phi_h$ is the similarity function of $\zeta$, which expresses the stability dependance of
563  the temperature and moisture gradients, and is specified differently for stable and unstable  the temperature and moisture gradients, and is specified differently for stable and unstable
564  layers according to Helfand and Schubert, 1995.  layers according to \cite{helfschu:95}.
565    
566  $\psi_g$ is the non-dimensional temperature or moisture gradient in the viscous sublayer,  $\psi_g$ is the non-dimensional temperature or moisture gradient in the viscous sublayer,
567  which is the mosstly laminar region between the surface and the tops of the roughness  which is the mosstly laminar region between the surface and the tops of the roughness
568  elements, in which temperature and moisture gradients can be quite large.  elements, in which temperature and moisture gradients can be quite large.
569  Based on Yaglom and Kader (1974):  Based on \cite{yagkad:74}:
570  \[  \[
571  \psi_{g} = { 0.55 (Pr^{2/3} - 0.2) \over \nu^{1/2} }  \psi_{g} = { 0.55 (Pr^{2/3} - 0.2) \over \nu^{1/2} }
572  (h_{0}u_{*} - h_{0_{ref}}u_{*_{ref}})^{1/2}  (h_{0}u_{*} - h_{0_{ref}}u_{*_{ref}})^{1/2}
# Line 588  The surface roughness length over oceans Line 580  The surface roughness length over oceans
580  {z_0} = c_1u^3_* + c_2u^2_* + c_3u_* + c_4 + {c_5 \over {u_*}}  {z_0} = c_1u^3_* + c_2u^2_* + c_3u_* + c_4 + {c_5 \over {u_*}}
581  \]  \]
582  where the constants are chosen to interpolate between the reciprocal relation of  where the constants are chosen to interpolate between the reciprocal relation of
583  Kondo(1975) for weak winds, and the piecewise linear relation of Large and Pond(1981)  \cite{kondo:75} for weak winds, and the piecewise linear relation of \cite{larpond:81}
584  for moderate to large winds.  Roughness lengths over land are specified  for moderate to large winds.  Roughness lengths over land are specified
585  from the climatology of Dorman and Sellers (1989).  from the climatology of \cite{dorsell:89}.
586    
587  For an unstable surface layer, the stability functions, chosen to interpolate between the  For an unstable surface layer, the stability functions, chosen to interpolate between the
588  condition of small values of $\beta$ and the convective limit, are the KEYPS function  condition of small values of $\beta$ and the convective limit, are the KEYPS function
589  (Panofsky, 1973) for momentum, and its generalization for heat and moisture:    (\cite{pano:73}) for momentum, and its generalization for heat and moisture:  
590  \[  \[
591  {\phi_m}^4 - 18 \zeta {\phi_m}^3 = 1 \hspace{1cm} ; \hspace{1cm}  {\phi_m}^4 - 18 \zeta {\phi_m}^3 = 1 \hspace{1cm} ; \hspace{1cm}
592  {\phi_h}^2 - 18 \zeta {\phi_h}^3 = 1 \hspace{1cm} .  {\phi_h}^2 - 18 \zeta {\phi_h}^3 = 1 \hspace{1cm} .
# Line 603  The function for heat and moisture assur Line 595  The function for heat and moisture assur
595  speed approaches zero.  speed approaches zero.
596    
597  For a stable surface layer, the stability functions are the observationally  For a stable surface layer, the stability functions are the observationally
598  based functions of Clarke (1970),  slightly modified for  based functions of \cite{clarke:70},  slightly modified for
599  the momemtum flux:    the momemtum flux:  
600  \[  \[
601  {\phi_m} = { { 1 + 5 {{\zeta}_1} } \over { 1 + 0.00794 {{\zeta}_1}  {\phi_m} = { { 1 + 5 {{\zeta}_1} } \over { 1 + 0.00794 {{\zeta}_1}
# Line 661  be $3 \hspace{.1cm} m$ where sea ice is Line 653  be $3 \hspace{.1cm} m$ where sea ice is
653  surface temperature of the ice.  surface temperature of the ice.
654    
655  $C_g$ is the total heat capacity of the ground, obtained by solving a heat diffusion equation  $C_g$ is the total heat capacity of the ground, obtained by solving a heat diffusion equation
656  for the penetration of the diurnal cycle into the ground (Blackadar, 1977), and is given by:  for the penetration of the diurnal cycle into the ground (\cite{black:77}), and is given by:
657  \[  \[
658  C_g = \sqrt{ {\lambda C_s \over 2\omega} } = \sqrt{(0.386 + 0.536W + 0.15W^2)2\times10^{-3}  C_g = \sqrt{ {\lambda C_s \over 2\omega} } = \sqrt{(0.386 + 0.536W + 0.15W^2)2\times10^{-3}
659  {86400 \over 2 \pi} } \, \, .  {86400 \over 2 \pi} } \, \, .
# Line 676  is a function of the ground wetness, $W$ Line 668  is a function of the ground wetness, $W$
668  Land Surface Processes:  Land Surface Processes:
669    
670  \paragraph{Surface Type}  \paragraph{Surface Type}
671  The fizhi package surface Types are designated using the Koster-Suarez (1992) mosaic  The fizhi package surface Types are designated using the Koster-Suarez (\cite{ks:91,ks:92})
672  philosophy which allows multiple ``tiles'', or multiple surface types, in any one  Land Surface Model (LSM) mosaic philosophy which allows multiple ``tiles'', or multiple surface
673  grid cell. The Koster-Suarez Land Surface Model (LSM) surface type classifications  types, in any one grid cell. The Koster-Suarez LSM surface type classifications
674  are shown in Table \ref{tab:fizhi:surftype}. The surface types and the percent of the grid  are shown in Table \ref{tab:fizhi:surftype}. The surface types and the percent of the grid
675  cell occupied by any surface type were derived from the surface classification of  cell occupied by any surface type were derived from the surface classification of
676  Defries and Townshend (1994), and information about the location of permanent  \cite{deftow:94}, and information about the location of permanent
677  ice was obtained from the classifications of Dorman and Sellers (1989).  ice was obtained from the classifications of \cite{dorsell:89}.
678  The surface type for the \txt GCM grid is shown in Figure \ref{fig:fizhi:surftype}.  The surface type map for a $1^\circ$ grid is shown in Figure \ref{fig:fizhi:surftype}.
679  The determination of the land or sea category of surface type was made from NCAR's  The determination of the land or sea category of surface type was made from NCAR's
680  10 minute by 10 minute Navy topography  10 minute by 10 minute Navy topography
681  dataset, which includes information about the percentage of water-cover at any point.  dataset, which includes information about the percentage of water-cover at any point.
682  The data were averaged to the model's \fxf and \txt grid resolutions,  The data were averaged to the model's grid resolutions,
683  and any grid-box whose averaged water percentage was $\geq 60 \%$ was  and any grid-box whose averaged water percentage was $\geq 60 \%$ was
684  defined as a water point. The \fxf grid Land-Water designation was further modified  defined as a water point. The Land-Water designation was further modified
685  subjectively to ensure sufficient representation from small but isolated land and water regions.  subjectively to ensure sufficient representation from small but isolated land and water regions.
686    
687  \begin{table}  \begin{table}
# Line 713  Type & Vegetation Designation \\ \hline Line 705  Type & Vegetation Designation \\ \hline
705  100 & Ocean \\ \hline  100 & Ocean \\ \hline
706  \end{tabular}  \end{tabular}
707  \end{center}  \end{center}
708  \caption{Surface type designations used to compute surface roughness (over land)  \caption{Surface type designations.}
 and surface albedo.}  
709  \label{tab:fizhi:surftype}  \label{tab:fizhi:surftype}
710  \end{table}  \end{table}
711    
   
712  \begin{figure*}[htbp]  \begin{figure*}[htbp]
713    \centerline{  \epsfysize=7in  \epsfbox{part6/surftypes.ps}}    \centerline{  \epsfysize=4.0in  \epsfbox{part6/surftype.eps}}
714    \vspace{0.3in}    \vspace{0.2in}
715    \caption  {Surface Type Compinations at \txt resolution.}    \caption  {Surface Type Combinations.}
716    \label{fig:fizhi:surftype}    \label{fig:fizhi:surftype}
717  \end{figure*}  \end{figure*}
718    
719  \begin{figure*}[htbp]  % \rotatebox{270}{\centerline{  \epsfysize=4in  \epsfbox{part6/surftypes.eps}}}
720    \centerline{  \epsfysize=7in  \epsfbox{part6/surftypes.descrip.ps}}  % \rotatebox{270}{\centerline{  \epsfysize=4in  \epsfbox{part6/surftypes.descrip.eps}}}
721    \vspace{0.3in}  %\begin{figure*}[htbp]
722    \caption  {Surface Type Descriptions.}  %  \centerline{  \epsfysize=4in  \epsfbox{part6/surftypes.descrip.ps}}
723    \label{fig:fizhi:surftype.desc}  %  \vspace{0.3in}
724  \end{figure*}  %  \caption  {Surface Type Descriptions.}
725    %  \label{fig:fizhi:surftype.desc}
726    %\end{figure*}
727    
728    
729  \paragraph{Surface Roughness}  \paragraph{Surface Roughness}
730  The surface roughness length over oceans is computed iteratively with the wind  The surface roughness length over oceans is computed iteratively with the wind
731  stress by the surface layer parameterization (Helfand and Schubert, 1991).  stress by the surface layer parameterization (\cite{helfschu:95}).
732  It employs an interpolation between the functions of Large and Pond (1981)  It employs an interpolation between the functions of \cite{larpond:81}
733  for high winds and of Kondo (1975) for weak winds.  for high winds and of \cite{kondo:75} for weak winds.
734    
735    
736  \paragraph{Albedo}  \paragraph{Albedo}
737  The surface albedo computation, described in Koster and Suarez (1991),  The surface albedo computation, described in \cite{ks:91},
738  employs the ``two stream'' approximation used in Sellers' (1987) Simple Biosphere (SiB)  employs the ``two stream'' approximation used in Sellers' (1987) Simple Biosphere (SiB)
739  Model which distinguishes between the direct and diffuse albedos in the visible  Model which distinguishes between the direct and diffuse albedos in the visible
740  and in the near infra-red spectral ranges. The albedos are functions of the observed  and in the near infra-red spectral ranges. The albedos are functions of the observed
# Line 751  sun), the greenness fraction, the vegeta Line 743  sun), the greenness fraction, the vegeta
743  Modifications are made to account for the presence of snow, and its depth relative  Modifications are made to account for the presence of snow, and its depth relative
744  to the height of the vegetation elements.  to the height of the vegetation elements.
745    
746  Gravity Wave Drag:  \paragraph{Gravity Wave Drag}
747    
748  The fizhi package employs the gravity wave drag scheme of Zhou et al. (1996).  The fizhi package employs the gravity wave drag scheme of \cite{zhouetal:95}).
749  This scheme is a modified version of Vernekar et al. (1992),  This scheme is a modified version of Vernekar et al. (1992),
750  which was based on Alpert et al. (1988) and Helfand et al. (1987).    which was based on Alpert et al. (1988) and Helfand et al. (1987).  
751  In this version, the gravity wave stress at the surface is  In this version, the gravity wave stress at the surface is
# Line 770  A modification introduced by Zhou et al. Line 762  A modification introduced by Zhou et al.
762  escape through the top of the model, although this effect is small for the current 70-level model.    escape through the top of the model, although this effect is small for the current 70-level model.  
763  The subgrid scale standard deviation is defined by $h$, and is not allowed to exceed 400 m.  The subgrid scale standard deviation is defined by $h$, and is not allowed to exceed 400 m.
764    
765  The effects of using this scheme within a GCM are shown in Takacs and Suarez (1996).  The effects of using this scheme within a GCM are shown in \cite{taksz:96}.
766  Experiments using the gravity wave drag parameterization yielded significant and  Experiments using the gravity wave drag parameterization yielded significant and
767  beneficial impacts on both the time-mean flow and the transient statistics of the  beneficial impacts on both the time-mean flow and the transient statistics of the
768  a GCM climatology, and have eliminated most of the worst dynamically driven biases  a GCM climatology, and have eliminated most of the worst dynamically driven biases
# Line 794  fields include:  sea surface temperature Line 786  fields include:  sea surface temperature
786  vegetation index, and the radiation-related background levels of: ozone, carbon dioxide,  vegetation index, and the radiation-related background levels of: ozone, carbon dioxide,
787  and stratospheric moisture.  and stratospheric moisture.
788    
789  Boundary condition data sets are available at the model's \fxf and \txt  Boundary condition data sets are available at the model's
790  resolutions for either climatological or yearly varying conditions.  resolutions for either climatological or yearly varying conditions.
791  Any frequency of boundary condition data can be used in the fizhi package;  Any frequency of boundary condition data can be used in the fizhi package;
792  however, the current selection of data is summarized in Table \ref{tab:fizhi:bcdata}\@.  however, the current selection of data is summarized in Table \ref{tab:fizhi:bcdata}\@.
793  The time mean values are interpolated during each model timestep to the  The time mean values are interpolated during each model timestep to the
794  current time. Future model versions will incorporate boundary conditions at  current time.
 higher spatial \mbox{($1^\circ$ x $1^\circ$)} resolutions.  
795    
796  \begin{table}[htb]  \begin{table}[htb]
797  \begin{center}  \begin{center}
# Line 827  current years and frequencies available. Line 818  current years and frequencies available.
818  Surface geopotential heights are provided from an averaging of the Navy 10 minute  Surface geopotential heights are provided from an averaging of the Navy 10 minute
819  by 10 minute dataset supplied by the National Center for Atmospheric Research (NCAR) to the  by 10 minute dataset supplied by the National Center for Atmospheric Research (NCAR) to the
820  model's grid resolution. The original topography is first rotated to the proper grid-orientation  model's grid resolution. The original topography is first rotated to the proper grid-orientation
821  which is being run, and then    which is being run, and then  averages the data to the model resolution.  
 averages the data to the model resolution.    
 The averaged topography is then passed through a Lanczos (1966) filter in both dimensions  
 which removes the smallest  
 scales while inhibiting Gibbs phenomena.    
   
 In one dimension, we may define a cyclic function in $x$ as:  
 \begin{equation}  
 f(x) = {a_0 \over 2} + \sum_{k=1}^N \left( a_k \cos(kx) + b_k \sin(kx) \right)  
 \label{eq:fizhi:filt}  
 \end{equation}  
 where $N = { {\rm IM} \over 2 }$ and ${\rm IM}$ is the total number of points in the $x$ direction.  
 Defining $\Delta x = { 2 \pi \over {\rm IM}}$, we may define the average of $f(x)$ over a  
 $2 \Delta x$ region as:  
   
 \begin{equation}  
 \overline {f(x)} = {1 \over {2 \Delta x}} \int_{x-\Delta x}^{x+\Delta x} f(x^{\prime}) dx^{\prime}  
 \label{eq:fizhi:fave1}  
 \end{equation}  
   
 Using equation (\ref{eq:fizhi:filt}) in equation (\ref{eq:fizhi:fave1}) and integrating, we may write:  
   
 \begin{equation}  
 \overline {f(x)} = {a_0 \over 2} + {1 \over {2 \Delta x}}  
 \sum_{k=1}^N \left [  
 \left. a_k { \sin(kx^{\prime}) \over k } \right /_{x-\Delta x}^{x+\Delta x} -  
 \left. b_k { \cos(kx^{\prime}) \over k } \right /_{x-\Delta x}^{x+\Delta x}  
 \right]  
 \end{equation}  
 or  
   
 \begin{equation}  
 \overline {f(x)} = {a_0 \over 2} + \sum_{k=1}^N {\sin(k \Delta x) \over {k \Delta x}}  
 \left( a_k \cos(kx) + b_k \sin(kx) \right)  
 \label{eq:fizhi:fave2}  
 \end{equation}  
   
 Thus, the Fourier wave amplitudes are simply modified by the Lanczos filter response  
 function ${\sin(k\Delta x) \over {k \Delta x}}$.  This may be compared with an $mth$-order  
 Shapiro (1970) filter response function, defined as $1-\sin^m({k \Delta x \over 2})$,  
 shown in Figure \ref{fig:fizhi:lanczos}.  
 It should be noted that negative values in the topography resulting from  
 the filtering procedure are {\em not} filled.  
   
 \begin{figure*}[htbp]  
   \centerline{  \epsfysize=7.0in  \epsfbox{part6/lanczos.ps}}  
   \caption{ \label{fig:fizhi:lanczos} Comparison between the Lanczos and $mth$-order Shapiro filter  
   response functions for $m$ = 2, 4, and 8. }  
 \end{figure*}  
822    
823  The standard deviation of the subgrid-scale topography  The standard deviation of the subgrid-scale topography is computed by interpolating the 10 minute
824  is computed from a modified version of the the Navy 10 minute by 10 minute dataset.  data to the model's resolution and re-interpolating back to the 10 minute by 10 minute resolution.
 The 10 minute by 10 minute topography is passed through a wavelet  
 filter in both dimensions which removes the scale smaller than 20 minutes.  
 The topography is then averaged to $1^\circ x 1^\circ$ grid resolution, and then  
 re-interpolated back to the 10 minute by 10 minute resolution.  
825  The sub-grid scale variance is constructed based on this smoothed dataset.  The sub-grid scale variance is constructed based on this smoothed dataset.
826    
827    
828  \paragraph{Upper Level Moisture}  \paragraph{Upper Level Moisture}
829  The fizhi package uses climatological water vapor data above 100 mb from the Stratospheric Aerosol and Gas  The fizhi package uses climatological water vapor data above 100 mb from the Stratospheric Aerosol and Gas
830  Experiment (SAGE) as input into the model's radiation packages.  The SAGE data is archived  Experiment (SAGE) as input into the model's radiation packages.  The SAGE data is archived
831  as monthly zonal means at 5$^\circ$ latitudinal resolution.  The data is interpolated to the  as monthly zonal means at $5^\circ$ latitudinal resolution.  The data is interpolated to the
832  model's grid location and current time, and blended with the GCM's moisture data.  Below 300 mb,  model's grid location and current time, and blended with the GCM's moisture data.  Below 300 mb,
833  the model's moisture data is used.  Above 100 mb, the SAGE data is used.  Between 100 and 300 mb,  the model's moisture data is used.  Above 100 mb, the SAGE data is used.  Between 100 and 300 mb,
834  a linear interpolation (in pressure) is performed using the data from SAGE and the GCM.  a linear interpolation (in pressure) is performed using the data from SAGE and the GCM.
# Line 898  a linear interpolation (in pressure) is Line 837  a linear interpolation (in pressure) is
837  \subsubsection{Fizhi Diagnostics}  \subsubsection{Fizhi Diagnostics}
838    
839  Fizhi Diagnostic Menu:  Fizhi Diagnostic Menu:
840  \label{sec:fizhi-diagnostics:menu}  \label{sec:pkg:fizhi:diagnostics}
841    
842  \begin{tabular}{llll}  \begin{tabular}{llll}
843  \hline\hline  \hline\hline
# Line 1430  Fizhi Diagnostic Description: Line 1369  Fizhi Diagnostic Description:
1369    
1370  In this section we list and describe the diagnostic quantities available within the  In this section we list and describe the diagnostic quantities available within the
1371  GCM.  The diagnostics are listed in the order that they appear in the  GCM.  The diagnostics are listed in the order that they appear in the
1372  Diagnostic Menu, Section \ref{sec:fizhi-diagnostics:menu}.  Diagnostic Menu, Section \ref{sec:pkg:fizhi:diagnostics}.
1373  In all cases, each diagnostic as currently archived on the output datasets  In all cases, each diagnostic as currently archived on the output datasets
1374  is time-averaged over its diagnostic output frequency:  is time-averaged over its diagnostic output frequency:
1375    
# Line 1588  $h_{0} = 30z_{0}$ with a maximum value o Line 1527  $h_{0} = 30z_{0}$ with a maximum value o
1527  \noindent  \noindent
1528  $\phi_h$ is the similarity function of $\zeta$, which expresses the stability dependance of  $\phi_h$ is the similarity function of $\zeta$, which expresses the stability dependance of
1529  the temperature and moisture gradients, specified differently for stable and unstable  the temperature and moisture gradients, specified differently for stable and unstable
1530  layers according to Helfand and Schubert, 1993. k is the Von Karman constant, $\zeta$ is the  layers according to \cite{helfschu:95}. k is the Von Karman constant, $\zeta$ is the
1531  non-dimensional stability parameter, Pr is the Prandtl number for air, $\nu$ is the molecular  non-dimensional stability parameter, Pr is the Prandtl number for air, $\nu$ is the molecular
1532  viscosity, $z_{0}$ is the surface roughness length, $u_*$ is the surface stress velocity  viscosity, $z_{0}$ is the surface roughness length, $u_*$ is the surface stress velocity
1533  (see diagnostic number 67), and the subscript ref refers to a reference value.  (see diagnostic number 67), and the subscript ref refers to a reference value.
# Line 1610  where $\psi_m$ is the surface layer non- Line 1549  where $\psi_m$ is the surface layer non-
1549  \noindent  \noindent
1550  $\phi_m$ is the similarity function of $\zeta$, which expresses the stability dependance of  $\phi_m$ is the similarity function of $\zeta$, which expresses the stability dependance of
1551  the temperature and moisture gradients, specified differently for stable and unstable layers  the temperature and moisture gradients, specified differently for stable and unstable layers
1552  according to Helfand and Schubert, 1993. k is the Von Karman constant, $\zeta$ is the  according to \cite{helfschu:95}. k is the Von Karman constant, $\zeta$ is the
1553  non-dimensional stability parameter, $u_*$ is the surface stress velocity  non-dimensional stability parameter, $u_*$ is the surface stress velocity
1554  (see diagnostic number 67), and $W_s$ is the magnitude of the surface layer wind.  (see diagnostic number 67), and $W_s$ is the magnitude of the surface layer wind.
1555  \\  \\
# Line 1622  non-dimensional stability parameter, $u_ Line 1561  non-dimensional stability parameter, $u_
1561  In the level 2.5 version of the Mellor-Yamada (1974) hierarchy, the turbulent heat or  In the level 2.5 version of the Mellor-Yamada (1974) hierarchy, the turbulent heat or
1562  moisture flux for the atmosphere above the surface layer can be expressed as a turbulent  moisture flux for the atmosphere above the surface layer can be expressed as a turbulent
1563  diffusion coefficient $K_h$ times the negative of the gradient of potential temperature  diffusion coefficient $K_h$ times the negative of the gradient of potential temperature
1564  or moisture. In the Helfand and Labraga (1988) adaptation of this closure, $K_h$  or moisture. In the \cite{helflab:88} adaptation of this closure, $K_h$
1565  takes the form:  takes the form:
1566  \[  \[
1567  {\bf ET} = K_h = -{( {\overline{w^{\prime}\theta_v^{\prime}}}) \over {\pp{\theta_v}{z}} }  {\bf ET} = K_h = -{( {\overline{w^{\prime}\theta_v^{\prime}}}) \over {\pp{\theta_v}{z}} }
# Line 1641  are functions of the Richardson number. Line 1580  are functions of the Richardson number.
1580    
1581  \noindent  \noindent
1582  For the detailed equations and derivations of the modified level 2.5 closure scheme,  For the detailed equations and derivations of the modified level 2.5 closure scheme,
1583  see Helfand and Labraga, 1988.  see \cite{helflab:88}.
1584    
1585  \noindent  \noindent
1586  In the surface layer, ${\bf {ET}}$ is the exchange coefficient for heat and moisture,  In the surface layer, ${\bf {ET}}$ is the exchange coefficient for heat and moisture,
# Line 1663  and $W_s$ is the magnitude of the surfac Line 1602  and $W_s$ is the magnitude of the surfac
1602  In the level 2.5 version of the Mellor-Yamada (1974) hierarchy, the turbulent heat  In the level 2.5 version of the Mellor-Yamada (1974) hierarchy, the turbulent heat
1603  momentum flux for the atmosphere above the surface layer can be expressed as a turbulent  momentum flux for the atmosphere above the surface layer can be expressed as a turbulent
1604  diffusion coefficient $K_m$ times the negative of the gradient of the u-wind.  diffusion coefficient $K_m$ times the negative of the gradient of the u-wind.
1605  In the Helfand and Labraga (1988) adaptation of this closure, $K_m$  In the \cite{helflab:88} adaptation of this closure, $K_m$
1606  takes the form:  takes the form:
1607  \[  \[
1608  {\bf EU} = K_m = -{( {\overline{u^{\prime}w^{\prime}}}) \over {\pp{U}{z}} }  {\bf EU} = K_m = -{( {\overline{u^{\prime}w^{\prime}}}) \over {\pp{U}{z}} }
# Line 1683  are functions of the Richardson number. Line 1622  are functions of the Richardson number.
1622    
1623  \noindent  \noindent
1624  For the detailed equations and derivations of the modified level 2.5 closure scheme,  For the detailed equations and derivations of the modified level 2.5 closure scheme,
1625  see Helfand and Labraga, 1988.  see \cite{helflab:88}.
1626    
1627  \noindent  \noindent
1628  In the surface layer, ${\bf {EU}}$ is the exchange coefficient for momentum,  In the surface layer, ${\bf {EU}}$ is the exchange coefficient for momentum,
# Line 2073  net surface upward longwave radiative fl Line 2012  net surface upward longwave radiative fl
2012  sea ice, $H$ is the upward sensible heat flux, $LE$ is the upward latent heat  sea ice, $H$ is the upward sensible heat flux, $LE$ is the upward latent heat
2013  flux, and $C_g$ is the total heat capacity of the ground.  flux, and $C_g$ is the total heat capacity of the ground.
2014  $C_g$ is obtained by solving a heat diffusion equation  $C_g$ is obtained by solving a heat diffusion equation
2015  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:
2016  \[  \[
2017  C_g = \sqrt{ {\lambda C_s \over {2 \omega} } } = \sqrt{(0.386 + 0.536W + 0.15W^2)2x10^{-3}  C_g = \sqrt{ {\lambda C_s \over {2 \omega} } } = \sqrt{(0.386 + 0.536W + 0.15W^2)2x10^{-3}
2018  { 86400. \over {2 \pi} } } \, \, .  { 86400. \over {2 \pi} } } \, \, .
# Line 2428  number 10), and $W_s$ is the surface win Line 2367  number 10), and $W_s$ is the surface win
2367    
2368  \noindent  \noindent
2369  Over the land surface, the surface roughness length is interpolated to the local  Over the land surface, the surface roughness length is interpolated to the local
2370  time from the monthly mean data of Dorman and Sellers (1989). Over the ocean,  time from the monthly mean data of \cite{dorsell:89}. Over the ocean,
2371  the roughness length is a function of the surface-stress velocity, $u_*$.  the roughness length is a function of the surface-stress velocity, $u_*$.
2372  \[  \[
2373  {\bf Z0} = c_1u^3_* + c_2u^2_* + c_3u_* + c_4 + {c_5 \over {u_*}}  {\bf Z0} = c_1u^3_* + c_2u^2_* + c_3u_* + c_4 + {c_5 \over {u_*}}
# Line 2436  the roughness length is a function of th Line 2375  the roughness length is a function of th
2375    
2376  \noindent  \noindent
2377  where the constants are chosen to interpolate between the reciprocal relation of  where the constants are chosen to interpolate between the reciprocal relation of
2378  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}
2379  for moderate to large winds.  for moderate to large winds.
2380  \\  \\
2381    
# Line 3032  q^{n+1} = (\pi q)^{n+1} / \pi^{n+1} Line 2971  q^{n+1} = (\pi q)^{n+1} / \pi^{n+1}
2971  \subsubsection{Dos and donts}  \subsubsection{Dos and donts}
2972    
2973  \subsubsection{Fizhi Reference}  \subsubsection{Fizhi Reference}
2974    
2975    \subsubsection{Experiments and tutorials that use fizhi}
2976    \label{sec:pkg:fizhi:experiments}
2977    
2978    \begin{itemize}
2979    \item{Global atmosphere experiment with realistic SST and topography in fizhi-cs-32x32x10 verification directory. }
2980    \item{Global atmosphere aqua planet experiment in fizhi-cs-aqualev20 verification directory. }
2981    \end{itemize}
2982    

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