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19990409: oabsfc

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  • Subject: 19990409: oabsfc
  • Date: Fri, 09 Apr 1999 12:32:17 -0600
>From: Brian Brong <address@hidden>
>Organization: .
>Keywords: 199904091718.LAA20322

>Steve,
>
>In the GEMPAK program OABSFC, the input parameter SEARCH:  What are the
>units of SEARCH?  Is it a physical distance (kilometers) or is it a grid
>point distance?
>
>Thanks for the Help
>Brian Brong
>
>

The objective analysis parameters are described in the tutorial:
http://www.unidata.ucar.edu/packages/gempak/tutorial/barnes.html

SEARCH is the exponential weighting in the term exp(-SEARCH),
eg SEARCH=20 corresponds to a value of 2x10-9, etc. such that
stations with weights less than that value are not included.
Don't confure SEARCH with the search radius.

The search radius, SRAD, is computed as SEARCH * WEIGHT, where
WEIGHT = 5.051457 * ( DELTAN * 2. / PI ) ** 2.

For more information, see the paper Koch and desJardins referenced
in the tutorial.

Steve Chiswell