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SST Update File & Plotting

This post was from a previous version of the WRF&MPAS-A Support Forum. New replies have been disabled and if you have follow up questions related to this post, then please start a new thread from the forum home page.



I am trying to better understand how the surface update file functions within the code. Specifically, how does the model update its SST and sea-ice values using the Does the srf_update file nudge the result each day or is there another method? I am unable to find the specific in the User Guide of Tutorial.

Also, when I try to plot my srf_update file using the plot_detla_sst.ncl script (following the tutorial directions) I get the follow error:

MPAS-Model/enso% setenv FNAME
MPAS-Model/enso% setenv GNAME
MPAS-Model/enso% bash
(NPL) zmenzo@cheyenne2:/glade/work/zmenzo/MPAS-Model/enso> ncl plot_delta_sst.ncl

Copyright (C) 1995-2017 - All Rights Reserved
University Corporation for Atmospheric Research
NCAR Command Language Version 6.4.0
The use of this software is governed by a License Agreement.
See for more details.
fatal:ContourPlotPreDraw: Workspace reallocation would exceed maximum size 100000000
fatal:ContourPlotDraw: draw error
fatal:plotManagerPreDraw: error in plot pre-draw
fatal:_NhlPlotManagerDraw: PreDraw error

I am assuming that this is due to the fact that I am using an x4.535554 grid and it is too high-resolution for the ncl script. Is this assumption correct? If so what is another quick way to render images with high-resolution meshes?

** I've also already tried to two quick fix solutions presented here (
Both of which do not produce an error or anything in fact. It runs the script and nothing happens.
The shortest explanation of the SST update methodology is that it provides a step change in the SST field in the model at each update time. I'd need to look through the code to better understand the details myself, and this is definitely something that we should provide documentation for in the User's Guide.

Regarding plotting, I think the error message you're seeing does indicate that the x4.535554 mesh contains too many cells for NCL to handle. If a "quick and dirty" plot of the SST difference is all that you're after, you could use the attached script, which is a modified version of the original plot_delta_sst.ncl script that generates contours from every Nth cell (with N being a parameter specified in the script as the variable "stride"). In the general case, which method you use to plot a field on the native MPAS mesh would probably depend on exactly what you're after: e.g., is it sufficient to display an interpolated field in an X11 window, or do you require an publication-quality vector graphic of the original, un-interpolated field?


  • plot_delta_sst_stride.ncl.txt
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