--- manual/s_phys_pkgs/text/seaice.tex 2005/07/18 20:45:27 1.4 +++ manual/s_phys_pkgs/text/seaice.tex 2008/01/15 23:58:53 1.6 @@ -1,4 +1,4 @@ -% $Header: /home/ubuntu/mnt/e9_copy/manual/s_phys_pkgs/text/seaice.tex,v 1.4 2005/07/18 20:45:27 molod Exp $ +% $Header: /home/ubuntu/mnt/e9_copy/manual/s_phys_pkgs/text/seaice.tex,v 1.6 2008/01/15 23:58:53 heimbach Exp $ % $Name: $ %%EH3 Copied from "MITgcm/pkg/seaice/seaice_description.tex" @@ -11,8 +11,123 @@ \end{rawhtml} +Authors: Martin Losch, Dimitris Menemenlis, An Nguyen, Jean-Michel Campin, +Patrick Heimbach, Chris Hill and Jinlun Zhang + +%---------------------------------------------------------------------- +\subsubsection{Introduction +\label{sec:pkg:exf:intro}} + + Package ``seaice'' provides a dynamic and thermodynamic interactive -sea-ice model. Sea-ice model thermodynamics are based on Hibler +sea-ice model. + +CPP options enable or disable different aspects of the package +(Section \ref{sec:pkg:seaice:config}). +Runtime options, flags, filenames and field-related dates/times are +set in \texttt{data.seaice} +(Section \ref{sec:pkg:seaice:runtime}). +A description of key subroutines is given in Section +\ref{sec:pkg:seaice:subroutines}. +Input fields, units and sign conventions are summarized in +Section \ref{sec:pkg:seaice:fields_units}, and available diagnostics +output is listed in Section \ref{sec:pkg:seaice:fields_diagnostics}. + +%---------------------------------------------------------------------- + +\subsubsection{SEAICE configuration, compiling \& running} + +\paragraph{Compile-time options +\label{sec:pkg:seaice:config}} +~ + +As with all MITgcm packages, SEAICE can be turned on or off at compile time +% +\begin{itemize} +% +\item +using the \texttt{packages.conf} file by adding \texttt{seaice} to it, +% +\item +or using \texttt{genmake2} adding +\texttt{-enable=seaice} or \texttt{-disable=seaice} switches +% +\item +\textit{required packages and CPP options}: \\ +SEAICE requires the external forcing package \texttt{exf} to be enabled; +no additional CPP options are required. +% +\end{itemize} +(see Section \ref{sect:buildingCode}). + +Parts of the SEAICE code can be enabled or disabled at compile time +via CPP preprocessor flags. These options are set in either +\texttt{SEAICE\_OPTIONS.h} or in \texttt{ECCO\_CPPOPTIONS.h}. +Table \ref{tab:pkg:seaice:cpp} summarizes these options. + +\begin{table}[h!] +\centering + \label{tab:pkg:seaice:cpp} + {\footnotesize + \begin{tabular}{|l|l|} + \hline + \textbf{CPP option} & \textbf{Description} \\ + \hline \hline + \texttt{SEAICE\_DEBUG} & + Enhance STDOUT for debugging \\ + \texttt{SEAICE\_ALLOW\_DYNAMICS} & + sea-ice dynamics code \\ + \texttt{SEAICE\_CGRID} & + LSR solver on C-grid (rather than original B-grid \\ + \texttt{SEAICE\_ALLOW\_EVP} & + use EVP rather than LSR rheology solver \\ + \texttt{SEAICE\_EXTERNAL\_FLUXES} & + use EXF-computed fluxes as starting point \\ + \texttt{SEAICE\_MULTICATEGORY} & + enable 8-category thermodynamics \\ + \texttt{SEAICE\_VARIABLE\_FREEZING\_POINT} & + enable linear dependence of the freezing point on salinity \\ + \texttt{ALLOW\_SEAICE\_FLOODING} & + enable snow to ice conversion for submerged sea-ice \\ + \texttt{SEAICE\_SALINITY} & + enable "salty" sea-ice \\ + \texttt{SEAICE\_CAP\_HEFF} & + enable capping of sea-ice thickness to MAX\_HEFF \\ + \hline + \end{tabular} + } + \caption{~} +\end{table} + +%---------------------------------------------------------------------- + +\subsubsection{Run-time parameters +\label{sec:pkg:seaice:runtime}} + +Run-time parameters are set in files +\texttt{data.pkg} (read in \texttt{packages\_readparms.F}), +and \texttt{data.seaice} (read in \texttt{seaice\_readparms.F}). + +\paragraph{Enabling the package} +~ \\ +% +A package is switched on/off at runtime by setting +(e.g. for SEAICE) \texttt{useSEAICE = .TRUE.} in \texttt{data.pkg}. + +\paragraph{General flags and parameters} +~ \\ +% +\input{part6/seaice-parms.tex} + + + +%---------------------------------------------------------------------- +\subsubsection{Description +\label{sec:pkg:seaice:descr}} + +[TO BE CONTINUED/MODIFIED] + +Sea-ice model thermodynamics are based on Hibler \cite{hib80}, that is, a 2-category model that simulates ice thickness and concentration. Snow is simulated as per Zhang et al. \cite{zha98a}. Although recent years have seen an increased use of @@ -66,5 +181,101 @@ atmospheric fields. +%---------------------------------------------------------------------- + +\subsubsection{Key subroutines +\label{sec:pkg:seaice:subroutines}} + +Top-level routine: \texttt{exf\_getforcing.F} + +{\footnotesize +\begin{verbatim} + +C !CALLING SEQUENCE: +c ... +c seaice_model (TOP LEVEL ROUTINE) +c | +c |-- #ifdef SEAICE_CGRID +c | SEAICE_DYNSOLVER +c | #ELSE +c | DYNSOLVER +c | #ENDIF +c | +c ... + +\end{verbatim} +} + + +%---------------------------------------------------------------------- + +\subsubsection{EXF diagnostics +\label{sec:pkg:seaice:diagnostics}} + +Diagnostics output is available via the diagnostics package +(see Section \ref{sec:pkg:diagnostics}). +Available output fields are summarized in +Table \ref{tab:pkg:seaice:diagnostics}. + +\begin{table}[h!] +\centering +\label{tab:pkg:seaice:diagnostics} +{\footnotesize +\begin{verbatim} +---------+----+----+----------------+----------------- + <-Name->|Levs|grid|<-- Units -->|<- Tile (max=80c) +---------+----+----+----------------+----------------- + SIarea | 1 |SM |m^2/m^2 |SEAICE fractional ice-covered area [0 to 1] + SIheff | 1 |SM |m |SEAICE effective ice thickness + SIuice | 1 |UU |m/s |SEAICE zonal ice velocity, >0 from West to East + SIvice | 1 |VV |m/s |SEAICE merid. ice velocity, >0 from South to North + SIhsnow | 1 |SM |m |SEAICE snow thickness + SIhsalt | 1 |SM |g/m^2 |SEAICE effective salinity + SIatmFW | 1 |SM |m/s |Net freshwater flux from the atmosphere (+=down) + SIuwind | 1 |SM |m/s |SEAICE zonal 10-m wind speed, >0 increases uVel + SIvwind | 1 |SM |m/s |SEAICE meridional 10-m wind speed, >0 increases uVel + SIfu | 1 |UU |N/m^2 |SEAICE zonal surface wind stress, >0 increases uVel + SIfv | 1 |VV |N/m^2 |SEAICE merid. surface wind stress, >0 increases vVel + SIempmr | 1 |SM |m/s |SEAICE upward freshwater flux, > 0 increases salt + SIqnet | 1 |SM |W/m^2 |SEAICE upward heatflux, turb+rad, >0 decreases theta + SIqsw | 1 |SM |W/m^2 |SEAICE upward shortwave radiat., >0 decreases theta + SIpress | 1 |SM |m^2/s^2 |SEAICE strength (with upper and lower limit) + SIzeta | 1 |SM |m^2/s |SEAICE nonlinear bulk viscosity + SIeta | 1 |SM |m^2/s |SEAICE nonlinear shear viscosity + SIsigI | 1 |SM |no units |SEAICE normalized principle stress, component one + SIsigII | 1 |SM |no units |SEAICE normalized principle stress, component two + SIthdgrh| 1 |SM |m/s |SEAICE thermodynamic growth rate of effective ice thickness + SIsnwice| 1 |SM |m/s |SEAICE ice formation rate due to flooding + SIuheff | 1 |UU |m^2/s |Zonal Transport of effective ice thickness + SIvheff | 1 |VV |m^2/s |Meridional Transport of effective ice thickness + ADVxHEFF| 1 |UU |m.m^2/s |Zonal Advective Flux of eff ice thickn + ADVyHEFF| 1 |VV |m.m^2/s |Meridional Advective Flux of eff ice thickn + DFxEHEFF| 1 |UU |m.m^2/s |Zonal Diffusive Flux of eff ice thickn + DFyEHEFF| 1 |VV |m.m^2/s |Meridional Diffusive Flux of eff ice thickn + ADVxAREA| 1 |UU |m^2/m^2.m^2/s |Zonal Advective Flux of fract area + ADVyAREA| 1 |VV |m^2/m^2.m^2/s |Meridional Advective Flux of fract area + DFxEAREA| 1 |UU |m^2/m^2.m^2/s |Zonal Diffusive Flux of fract area + DFyEAREA| 1 |VV |m^2/m^2.m^2/s |Meridional Diffusive Flux of fract area + ADVxSNOW| 1 |UU |m.m^2/s |Zonal Advective Flux of eff snow thickn + ADVySNOW| 1 |VV |m.m^2/s |Meridional Advective Flux of eff snow thickn + DFxESNOW| 1 |UU |m.m^2/s |Zonal Diffusive Flux of eff snow thickn + DFyESNOW| 1 |VV |m.m^2/s |Meridional Diffusive Flux of eff snow thickn + ADVxSSLT| 1 |UU |psu.m^2/s |Zonal Advective Flux of seaice salinity + ADVySSLT| 1 |VV |psu.m^2/s |Meridional Advective Flux of seaice salinity + DFxESSLT| 1 |UU |psu.m^2/s |Zonal Diffusive Flux of seaice salinity + DFyESSLT| 1 |VV |psu.m^2/s |Meridional Diffusive Flux of seaice salinity +\end{verbatim} +} +\caption{~} +\end{table} + + %\subsubsection{Package Reference} +\subsubsection{Experiments and tutorials that use seaice} +\label{sec:pkg:seaice:experiments} + +\begin{itemize} +\item{Labrador Sea experiment in lab\_sea verification directory. } +\end{itemize} +