How to extract wind(zonal & meridional), geopotential height using the convert_mpas include_field

Questions, issues, or suggestions related to post-processing of model output.
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makinde
Posts: 6
Joined: Sat May 09, 2020 5:40 pm

How to extract wind(zonal & meridional), geopotential height using the convert_mpas include_field

Post by makinde » Tue May 19, 2020 1:10 am

Good day,
Thanks for being a help to us newbies.
I am writing to find how to post-process wind components and geopotential Height across all levels from the MPAS model.

I have ran a 10 day variable resolution simulation with MPAS and I am about to analyze, since I don't know much about how the model runs or the variables the model produces, I have gotten some stream_list.atmosphere.(diagnostics, output) ( all attached including the namelist and the streams.atmosphere) to run the model. In those files, I found numerous variable name there, but couldn't found (or notice) any one of them to give the idea of u(zonal wind component) or v(meridional wind component), geopotential height and vertical windspeed at levels.

I have configured the simulations to output diagnostics file at every day as below:

//////////////////////////////////
diag.2009-01-01_00.00.00.nc
diag.2009-01-02_00.00.00.nc
diag.2009-01-03_00.00.00.nc
diag.2009-01-04_00.00.00.nc
///////////////////////////////////


I want to post-process u, v, geopotential height and the vertical from the diag file using convert_mpas tool to get a single file (latlon.nc), but I don't know which of the variable names in the output and the diagnostic stream_list I should include in the convert_mpas include_field.

Please can anyone put me through this?

I have gone through the user guide, but couldn't find useful information about these particular variables, may they need to be calculated?
If so, at least I will need some other parameters (variables) like wind speed to calculate some of the above listed variables.

please any help will be appreciated.


Thanks so much for your usual help.
Attachments
streams.atmosphere.txt
(810 Bytes) Downloaded 4 times
stream_list.atmosphere.output.txt
(927 Bytes) Downloaded 3 times
stream_list.atmosphere.diagnostics.txt
(1.17 KiB) Downloaded 3 times
namelist.atmosphere.txt
(1.73 KiB) Downloaded 3 times

mgduda
Posts: 319
Joined: Mon Feb 26, 2018 7:35 pm

Re: How to extract wind(zonal & meridional), geopotential height using the convert_mpas include_field

Post by mgduda » Wed May 27, 2020 6:02 pm

I sincerely apologize for the long delay in replying!

The zonal and meridional components of the horizontal wind field are available as the 'uReconstructZonal' and 'uReconstructMeridional' fields. These are not included in the diagnostics output files by default, but you can add them to your stream_list.atmosphere.diagnostics file before starting the model simulation. Internally, the model interpolates the prognosed normal component of horizontal wind at cell faces ("edges") to cell centers using radial basis functions; so, the 'uReconstructZonal' and 'uReconstructMeridional' fields are horizontally located at the nominal centers of grid cells. In the vertical, these fields are located at the midpoint of layers in the model's smoothed terrain-following vertical coordinate.

At present, there is no geopotential height field available directly from the model. However, in the model initial conditions file ('x6.999426.init.nc'), there should be a field named 'zgrid'. The 'zgrid' field provides the geometric height at the layer interfaces in each column of the model grid, which you could use to compute geopotential height. The geometric height of layer midpoints (where the 'uReconstructZonal' and 'uReconstructMeridional' fields are located vertically) is simply the average of the heights of layer interfaces at the bottom and at the top of each layer.

Apologies, again, for the slow reply, and please don't hesitate to follow-up in this thread if there are any details that I can clarify!
NCAR/MMM

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