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[IDV #TPK-509064]: model output sounding table heights

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  • Subject: [IDV #TPK-509064]: model output sounding table heights
  • Date: Thu, 15 Dec 2016 12:57:05 -0700
Hi Mike,

What you want is a "better" derivation of height. What you currently have is the
International Standard Atmosphere (ISA) [1] derivation which is why the heights
are consistent no matter the data. There is sufficient model data, in theory, to
provide other derivations, but they are still derivations based themselves on
model data with their own built-in assumptions. I'm not sure they will be
necessarily "better".

I'll have to chat with the scientists here to understand if it even makes sense,
scientifically speaking, to provide additional derivations of the height. My
guess is the data as they are presented is standard modelling practice. My fear
is that providing a more "accurate" derivation will give you a false sense of
what is really going on.

[1] http://weatherfaqs.org.uk/book/export/html/174

Best,

Unidata IDV Support

> I'm plotting soundings from various days/models and then saving the table
> to open in sharppy.  I'm manually fixing the actual surface elevation by
> looking it up for various places, as idv plots straight to sea level.
> Easy enough.  I noticed no matter the day or area, all the pressure
> height elevations are the same above the surface.  Say 850 for example
> no matter the conditions/day is plotted at 1457 meters above sea level.
> All heights stay identical day to day.  Is this not a problem?
> 
> Say I click on COD's soundings, one for today right around Omaha and
> then again Sunday when it is super cold.  It would give 850mb as 1504
> then 1474. While no matter the day IDV's table will give 850 the same
> number as well as every height.
> 
> I have roughly 150 days of storm events I was going to go through manually
> editing these from IDV for the surface elevation and also then modifying
> them for the surface conditions that day.  I'm just trying to wrap my head
> around if it's going to be ok when the heights at each plotted level never
> change.  It doesn't seem it would be but it must.  Or it's just a close
> enough deal?  Or maybe most likely I'm just completely missing something.
> 
> Thanks,
> 
> Mike
> 
> 


Ticket Details
===================
Ticket ID: TPK-509064
Department: Support IDV
Priority: Normal
Status: Closed
===================
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