# Changeset 10462

Ignore:
Timestamp:
2019-01-07T16:39:04+01:00 (3 years ago)
Message:

Fill in section on closea module in NEMO book. Ticket #2000.

File:
1 edited

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Unmodified
 r10442 %>>>>>>>>>>>>>>>>>>>>>>>>>>>> %>>>>>>>>>>>>>>>>>>>>>>>>>>>> \begin{figure}[!tbp] \begin{center} \includegraphics[width=1.0\textwidth]{Fig_closea_mask_example} \caption{ \protect\label{fig:closea_mask_example} Example of mask fields for the closea module. \textit{Left}: a closea\_mask field; \textit{Right}: a closea\_mask\_rnf field. In this example, if ln\_closea is set to .true., the mean freshwater flux over each of the American Great Lakes will be set to zero, and the total residual for all the lakes, if negative, will be put into the St Laurence Seaway in the area shown. } \end{center} \end{figure} %>>>>>>>>>>>>>>>>>>>>>>>>>>>> % ================================================================ \label{sec:MISC_closea} \colorbox{yellow}{Add here a short description of the way closed seas are managed} Some configurations include inland seas and lakes as ocean points. This is particularly the case for configurations that are coupled to an atmosphere model where one might want to include inland seas and lakes as ocean model points in order to provide a better bottom boundary condition for the atmosphere. However there is no route for freshwater to run off from the lakes to the ocean and this can lead to large drifts in the sea surface height over the lakes. The closea module provides options to either fill in closed seas and lakes at run time, or to set the net surface freshwater flux for each lake to zero and put the residual flux into the ocean. Prior to NEMO 4 the locations of inland seas and lakes was set via hardcoded indices for various ORCA configurations. From NEMO 4 onwards the inland seas and lakes are defined using mask fields in the domain configuration file. The options are as follows. \begin{enumerate} \item{{\bf No closea\_mask'' field is included in domain configuration file.} In this case the closea module does nothing.} \item{{\bf A field called closea\_mask is included in the domain configuration file and ln\_closea=.false. in namelist namcfg.} In this case the inland seas defined by the closea\_mask field are filled in (turned to land points) at run time. That is every point in closea\_mask that is nonzero is set to be a land point.} \item{{\bf A field called closea\_mask is included in the domain configuration file and ln\_closea=.true. in namelist namcfg.} Each inland sea or group of inland seas is set to a positive integer value in the closea\_mask field (see Figure \ref{fig:closea_mask_example} for an example). The net surface flux over each inland sea or group of inland seas is set to zero each timestep and the residual flux is distributed over the global ocean (ie. all ocean points where closea\_mask is zero).} \item{{\bf Fields called closea\_mask and closea\_mask\_rnf are included in the domain configuration file and ln\_closea=.true. in namelist namcfg.} This option works as for option 3, except that if the net surface flux over an inland sea is negative (net precipitation) it is put into the ocean at specified runoff points. A net positive surface flux (net evaporation) is still spread over the global ocean. The mapping from inland seas to runoff points is defined by the closea\_mask\_rnf field. Each mapping is defined by a positive integer value for the inland sea(s) and the corresponding runoff points. An example is given in Figure \ref{fig:closea_mask_example}. If no mapping is provided for a particular inland sea then the residual is spread over the global ocean.} \item{{\bf Fields called closea\_mask and closea\_mask\_emp are included in the domain configuration file and ln\_closea=.true. in namelist namcfg.} This option works the same as option 4 except that the nonzero net surface flux is sent to the ocean at the specified runoff points regardless of whether it is positive or negative. The mapping from inland seas to runoff points in this case is defined by the closea\_mask\_emp field.} \end{enumerate} There is a python routine to create the closea\_mask fields and append them to the domain configuration file in the utils/tools/DOMAINcfg directory. % ================================================================