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[GEMPAK #UMR-423080]: CAPE differences in GEMPAK vs. NSHARP

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  • Subject: [GEMPAK #UMR-423080]: CAPE differences in GEMPAK vs. NSHARP
  • Date: Wed, 14 Nov 2007 15:41:10 -0700
Chris,

NSHARP defaults to the most unstable level unless you have set the level
to do the PARCEL from. The GFUNC expression will use the information from the 
level you provided.
The only other difference to check is that NSHARP only plots data to 100mb, 
whereas
the GFUNC calculation will keep lifting  to higher levels if they exist and 
assuming you havn't
run into the negative levels by theat point.

Steve Chiswell
Unidata User Support


> Hey,
> 
> I have a quick question on computations I made a while back.  I am getting 
> differences in the results for CAPE when comparing GEMPAK and NSHARP that are 
> not substantial (like usually less than 100 J/kg) but still has me curious.
> 
> In GEMPAK,  I use the following specification for several different pressure 
> levels:
> 
> GFUNC    = CAPE(pres,hght,tvrc,dwpc)
> 
> Both this computation and NSHARP utilize a virtual temperature correction.  
> So what is the crucial detail and difference I'm missing?
> 
> Thank you in advance,
> Chris
> 
> ___________________________________________________________
> Christopher J. Melick
> Ph.D. Student, Atmospheric Science
> Department of Soil, Env, and Atmos Sciences
> University of Missouri-Columbia
> 302 ABNR Building
> Columbia, MO 65211
> 
> address@hidden
> (573)-239-3999  cell
> (573)-882-7739  work
> 
> 
> 
> 
> 


Ticket Details
===================
Ticket ID: UMR-423080
Department: Support GEMPAK
Priority: Normal
Status: Closed