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\section{Fizhi: High-end Atmospheric Physics} |
\section{Fizhi: High-end Atmospheric Physics} |
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\label{sec:pkg:fizhi} |
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\begin{rawhtml} |
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<!-- CMIREDIR:package_fizhi: --> |
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\end{rawhtml} |
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\input{texinputs/epsf.tex} |
\input{texinputs/epsf.tex} |
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\subsection{Introduction} |
\subsection{Introduction} |
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\subsubsection{Moist Convective Processes} |
\subsubsection{Moist Convective Processes} |
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\subsubsection{Sub-grid and Large-scale Convection} |
\paragraph{Sub-grid and Large-scale Convection} |
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\label{sec:fizhi:mc} |
\label{sec:fizhi:mc} |
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Sub-grid scale cumulus convection is parameterized using the Relaxed Arakawa |
Sub-grid scale cumulus convection is parameterized using the Relaxed Arakawa |
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lower layers in a process identical to the re-evaporation of convective rain. |
lower layers in a process identical to the re-evaporation of convective rain. |
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\subsubsection{Cloud Formation} |
\paragraph{Cloud Formation} |
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\label{sec:fizhi:clouds} |
\label{sec:fizhi:clouds} |
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Convective and large-scale cloud fractons which are used for cloud-radiative interactions are determined |
Convective and large-scale cloud fractons which are used for cloud-radiative interactions are determined |
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\begin{figure*}[htbp] |
\begin{figure*}[htbp] |
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\vspace{0.4in} |
\vspace{0.4in} |
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\centerline{ \epsfysize=4.0in \epsfbox{rhcrit.ps}} |
\centerline{ \epsfysize=4.0in \epsfbox{part6/rhcrit.ps}} |
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\vspace{0.4in} |
\vspace{0.4in} |
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\caption [Critical Relative Humidity for Clouds.] |
\caption [Critical Relative Humidity for Clouds.] |
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{Critical Relative Humidity for Clouds.} |
{Critical Relative Humidity for Clouds.} |
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of latitude and height (Rosenfield, et al., 1987) are linearly interpolated to the current time. |
of latitude and height (Rosenfield, et al., 1987) are linearly interpolated to the current time. |
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\subsubsection{Shortwave Radiation} |
\paragraph{Shortwave Radiation} |
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The shortwave radiation package used in the package computes solar radiative |
The shortwave radiation package used in the package computes solar radiative |
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heating due to the absoption by water vapor, ozone, carbon dioxide, oxygen, |
heating due to the absoption by water vapor, ozone, carbon dioxide, oxygen, |
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\begin{figure*}[htbp] |
\begin{figure*}[htbp] |
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\vspace{0.4in} |
\vspace{0.4in} |
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\centerline{ \epsfysize=4.0in %\epsfbox{rhcrit.ps} |
\centerline{ \epsfysize=4.0in %\epsfbox{part6/rhcrit.ps} |
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} |
} |
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\vspace{0.4in} |
\vspace{0.4in} |
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\caption {Low-Middle-High Cloud Configurations} |
\caption {Low-Middle-High Cloud Configurations} |
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\end{figure*} |
\end{figure*} |
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\subsubsection{Longwave Radiation} |
\paragraph{Longwave Radiation} |
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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 Chou and Suarez (1994). |
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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 |
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assigned. |
assigned. |
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\subsubsection{Cloud-Radiation Interaction} |
\paragraph{Cloud-Radiation Interaction} |
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\label{sec:fizhi:radcloud} |
\label{sec:fizhi:radcloud} |
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The cloud fractions and diagnosed cloud liquid water produced by moist processes |
The cloud fractions and diagnosed cloud liquid water produced by moist processes |
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Once all the diffusion coefficients are calculated, the diffusion equations are solved numerically |
Once all the diffusion coefficients are calculated, the diffusion equations are solved numerically |
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using an implicit backward operator. |
using an implicit backward operator. |
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\subsubsection{Atmospheric Boundary Layer} |
\paragraph{Atmospheric Boundary Layer} |
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The depth of the atmospheric boundary layer (ABL) is diagnosed by the parameterization as the |
The depth of the atmospheric boundary layer (ABL) is diagnosed by the parameterization as the |
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level at which the turbulent kinetic energy is reduced to a tenth of its maximum near surface value. |
level at which the turbulent kinetic energy is reduced to a tenth of its maximum near surface value. |
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The vertical structure of the ABL is explicitly resolved by the lowest few (3-8) model layers. |
The vertical structure of the ABL is explicitly resolved by the lowest few (3-8) model layers. |
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\subsubsection{Surface Energy Budget} |
\paragraph{Surface Energy Budget} |
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The ground temperature equation is solved as part of the turbulence package |
The ground temperature equation is solved as part of the turbulence package |
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using a backward implicit time differencing scheme: |
using a backward implicit time differencing scheme: |
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\subsubsection{Land Surface Processes} |
\subsubsection{Land Surface Processes} |
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\subsubsection{Surface Type} |
\paragraph{Surface Type} |
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The fizhi package surface Types are designated using the Koster-Suarez (1992) mosaic |
The fizhi package surface Types are designated using the Koster-Suarez (1992) mosaic |
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philosophy which allows multiple ``tiles'', or multiple surface types, in any one |
philosophy which allows multiple ``tiles'', or multiple surface types, in any one |
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grid cell. The Koster-Suarez Land Surface Model (LSM) surface type classifications |
grid cell. The Koster-Suarez Land Surface Model (LSM) surface type classifications |
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\begin{figure*}[htbp] |
\begin{figure*}[htbp] |
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\centerline{ \epsfysize=7in \epsfbox{surftypes.ps}} |
\centerline{ \epsfysize=7in \epsfbox{part6/surftypes.ps}} |
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\vspace{0.3in} |
\vspace{0.3in} |
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\caption {Surface Type Compinations at \txt resolution.} |
\caption {Surface Type Compinations at \txt resolution.} |
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\label{fig:fizhi:surftype} |
\label{fig:fizhi:surftype} |
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\end{figure*} |
\end{figure*} |
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\begin{figure*}[htbp] |
\begin{figure*}[htbp] |
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\centerline{ \epsfysize=7in \epsfbox{surftypes.descrip.ps}} |
\centerline{ \epsfysize=7in \epsfbox{part6/surftypes.descrip.ps}} |
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\vspace{0.3in} |
\vspace{0.3in} |
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\caption {Surface Type Descriptions.} |
\caption {Surface Type Descriptions.} |
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\label{fig:fizhi:surftype.desc} |
\label{fig:fizhi:surftype.desc} |
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\end{figure*} |
\end{figure*} |
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\subsubsection{Surface Roughness} |
\paragraph{Surface Roughness} |
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The surface roughness length over oceans is computed iteratively with the wind |
The surface roughness length over oceans is computed iteratively with the wind |
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stress by the surface layer parameterization (Helfand and Schubert, 1991). |
stress by the surface layer parameterization (Helfand and Schubert, 1991). |
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It employs an interpolation between the functions of Large and Pond (1981) |
It employs an interpolation between the functions of Large and Pond (1981) |
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for high winds and of Kondo (1975) for weak winds. |
for high winds and of Kondo (1975) for weak winds. |
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\subsubsection{Albedo} |
\paragraph{Albedo} |
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The surface albedo computation, described in Koster and Suarez (1991), |
The surface albedo computation, described in Koster and Suarez (1991), |
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employs the ``two stream'' approximation used in Sellers' (1987) Simple Biosphere (SiB) |
employs the ``two stream'' approximation used in Sellers' (1987) Simple Biosphere (SiB) |
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Model which distinguishes between the direct and diffuse albedos in the visible |
Model which distinguishes between the direct and diffuse albedos in the visible |
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\end{table} |
\end{table} |
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\subsubsection{Topography and Topography Variance} |
\paragraph{Topography and Topography Variance} |
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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 |
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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 |
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the filtering procedure are {\em not} filled. |
the filtering procedure are {\em not} filled. |
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\begin{figure*}[htbp] |
\begin{figure*}[htbp] |
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\centerline{ \epsfysize=7.0in \epsfbox{lanczos.ps}} |
\centerline{ \epsfysize=7.0in \epsfbox{part6/lanczos.ps}} |
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\caption{ \label{fig:fizhi:lanczos} Comparison between the Lanczos and $mth$-order Shapiro filter |
\caption{ \label{fig:fizhi:lanczos} Comparison between the Lanczos and $mth$-order Shapiro filter |
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response functions for $m$ = 2, 4, and 8. } |
response functions for $m$ = 2, 4, and 8. } |
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\end{figure*} |
\end{figure*} |
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The sub-grid scale variance is constructed based on this smoothed dataset. |
The sub-grid scale variance is constructed based on this smoothed dataset. |
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\subsubsection{Upper Level Moisture} |
\paragraph{Upper Level Moisture} |
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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 |
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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 |
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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 |
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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, |
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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. |
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\subsection{Key subroutines, parameters and files} |
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\subsection{Dos and donts} |
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\subsection{Fizhi Reference} |