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[GEMPAK #NJA-189011]: Height equation.

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  • Subject: [GEMPAK #NJA-189011]: Height equation.
  • Date: Mon, 05 Jun 2006 11:20:24 -0600
> Steve,
> 
> I have an individual grid with a gvcord of CCBL, glevel of 0, and the
> parameter is PRES.  Basically, it is the pressure at the convective
> cloud base.
> 
> In the collection of grids with this individual grid, I have tmpk,
> relh, hght, and other parameters every 25 to 50 mb.  I also have a
> hght grid for the surface.
> 
> I'm trying to convert the above listed individual grid from PRES to
> ZAGL.  The gdvint is not really set up for what I'm trying to do - it
> quickly converts the pressure levels from the original grid set to
> discrete HGHT levels . . . but I really just want the CCBL ZAGL.
> 
> Any ideas?
> 
> Stonie
> 
> 


Stonie,

As an interpolaion function, you could proceed the way I did with the dfprcl 
for cape/cins to
find every level and then interpolate the height from the surrounding pressure 
levels.

I answered a question a while back about how to graphically plot PRES@0%TROP in 
gdcross,
where if that was sufficient, you can calculate the QUO(PRES@0@CCBL,PRES) 
at each level in your data set, and then plot the contour value of 1.0 for the 
above, eg:
http://www.unidata.ucar.edu/support/help/MailArchives/gempak/msg04168.html

Otherwise, if you actually need the grid values for the ZAGL, then an standard 
interpolation
function would be route. I can put it on the burner, but am burried at the 
moment for a while.

Steve Chiswell
Unidata User Support


Ticket Details
===================
Ticket ID: NJA-189011
Department: Support GEMPAK
Priority: Normal
Status: Closed