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[IDV #OVR-601731]: IDV Problems Using CF Compliant WRF Files

> Yuan,
> 
> The file "sandyC300000sigmaMF.nc" displays CORRECTLY, but I need to 
> DE-STAGGER (as you advised many months ago) for more efficient processing by 
> IDV. I also needed to DE-PERTURB the theta, pressure, and geopotential 
> variables, because they were not being processed properly by IDV. I decided 
> to do my WRF file post-processing using an NCL script, the output of which is 
> "out.nc".
> 
> Unfortunately, as much as I try to simply COPY a variable (such as QVAPOR in 
> my test cases), its attributes, and dimensions using NCL, none of the 3D 
> variables display as 0 to 6000 meters on the vertical scale of the vertical 
> cross section plots in IDV when using the OUTPUT of my NCL script ("out.nc"), 
> even though they all scaled as 0 to 6000 meters for the 
> "sandyC300000sigmaMF.nc" INPUT file to my NCL script.
> 
> Regarding staggering, my aim is to DE-STAGGER, so I would not expect to need 
> stagger data in my file. I only put it back in per your advice on the 
> attached email.
> 
> Jim
> 
If I understand you correctly, what you are doing now is to create a stagger 
gridded output to DE-PERTURB those variables.
If so, this might be an issue here.

In a corrected stagger gridded file, the vertical coordinate is based on the 
PH, PHB, P, and PB:
<coordTransform name="WRFEta" type="Vertical">
    <param name="height formula" value="height(x,y,z) = (PH(x,y,z) + 
PHB(x,y,z)) / 9.81" />
    <param name="perturbation_geopotential" value="PH" />
    <param name="base_geopotential" value="PHB" />
    <param name="pressure formula" value="pressure(x,y,z) = P(x,y,z) + 
PB(x,y,z)" />
    <param name="perturbation_presure" value="P" />
    <param name="base_presure" value="PB" />
    <param name="staggered_x" value="false" />
    <param name="staggered_y" value="false" />
    <param name="staggered_z" value="false" />
    <param name="eta" value="z" />
  </coordTransform>

If you add these four variable back, it should work correctly.


Yuan


Ticket Details
===================
Ticket ID: OVR-601731
Department: Support IDV
Priority: High
Status: Open
===================
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