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[IDV #NYF-936499]: Formulas and Grib Files

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  • Subject: [IDV #NYF-936499]: Formulas and Grib Files
  • Date: Wed, 26 Aug 2009 16:30:43 -0600
Hi Greg,

> 
> Regrettably, the surface wet bulb temperature is not a grib parameter
> in most of the model grib files. However, I was curious as to whether
> or not it was possible to create a new variable based on a formula, and
> then either write a new grib file, or add the new variable to the old
> grib and then write that revised file. Let me know if you get a minute.
> Thanks!

Yes it is possible to write a formula (not sure what the calculation would be 
to create a surface wet bulb temp though). See the user guide and workshop 
pages:
http://www.unidata.ucar.edu/software/idv/docs/userguide/tools/Formulas.html
http://www.unidata.ucar.edu/software/idv/docs/workshop/formulas/index.html

You cannot write a new grib file or add to an existing one. However, you can 
write the results of the formula out as a netcdf grid file.
From any display of gridded data you can write out the data. see:
http://www.unidata.ucar.edu/software/idv/docs/workshop/savingstate/SavingData.html
You can also right click on the formula and choose "Evaluate and Save"


> 
> I work for a television station in Raleigh, NC, and we continue
> to push the envelope as to what kind of datasets we can display on the
> air. This request is simply part of that effort. Thanks again.
> 

Cool.

-Jeff



Ticket Details
===================
Ticket ID: NYF-936499
Department: Support IDV
Priority: Normal
Status: Closed