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20030806: making SNMOD file with feet instead of pres

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  • Subject: 20030806: making SNMOD file with feet instead of pres
  • Date: Thu, 28 Aug 2003 13:22:21 -0600
Dusty,

Any introductory meteorology text would describe the hypsometric
equation which relates change in pressure to change in height.
It is an integrated quantity based on the temperature of each layer
in the atmosphere.

I would suggest always using SI units (meters for height and meters per second
for wind speed) since publications will generally always ask for that.

Steve Chiswell

>From: <address@hidden>
>Organization: UCAR/Unidata
>Keywords: 200308061928.h76JSRLd022412

>Steve,
>
>I know that I've pretty much asked this question before but I'm haveing a lot 
> of trouble with it.  When I create a SNMOD file of my data and change VCOORD 
> to HGFT and then try to open that file and display the graph in SNCROSS  I do
> n't get back anything on the graph.  The X window will pop up and display a c
> oordinat system of time v. elevation in feet but nothing will graph and when 
> I change it run the orginal file in VCOORD = PRES everything works good.  Don
> 't quite now what I'm doing wrong.  I even tried changing MRGDAT=YES and NO s
> till nothing comes up on the graph.  
>
>Also I have searched the web for the equation that converts pressure in millib
> ars to feet and couldn't find anything (is there such a thing?). Or is it jus
> t a approximation.
>
>thanks,
>Dusty
>