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[IDV #SII-492455]: IDV - ECMWF model levels -> pressure levels

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  • Subject: [IDV #SII-492455]: IDV - ECMWF model levels -> pressure levels
  • Date: Fri, 26 Jan 2007 16:41:36 -0700
Hi HP-

> Institution: EUMETSAT
> Package Version: 2.2b1
> Operating System: Windows XP
> Hardware Information: Java: home: C:\\Program Files\\IDV_2.2b1\\jre version: 
> 1.5.0_06 j3d:1.3.2 fcs (build12)
> Inquiry: Hi
> 
> I am not sure where in IDV the following problem should be solved.
> 
> ECMWF's operational model archives numerical fields at pressure and model 
> levels.
> With model levels one gets much higher vertical resolution as compared to the
> standard pressure levels only. This e.g. is attractive when looking for 
> boundary layer
> inversions creating soundings (see another Support Request). However, IDV 
> gets lost when decoding a GRIB file containing model levels
> (see attached sample). For convenience I also attach a chapter from the ECMWF
> documentation that explains the dirctization issue. The full document may be 
> found at
> 
> http://www.ecmwf.int/research/ifsdocs/CY28r1/index.html
> 
> Can this be straightened out?

The IDV currently can't handle quasi-regular (thinned) grids
in GRIB 1 format but does handle them in GRIB2 format.  That
accounts for the "lost" part.

For the hybrid levels, right now we scale them to the vertical
axis in the display.  So, if you can get them on regular grids
or in GRIB2 format, you can then set your vertical axis to the
range of the vertical levels (e.g. 0-50).

Don Murray

Ticket Details
===================
Ticket ID: SII-492455
Department: Support IDV
Priority: Emergency
Status: Open