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Jimmy, To clarify, gdobscnt uses RADIUS, not SEARCH. This program was written in response to a user support question I had to count the number of observations within a certain radius. It is not doing objective analysis. You could estimate this using RADIUS equal to SRAD as defined below. The SEARCH parameter used in OABSFC is a number (not a distance) used to determine if the weight contributed by a member is greater than EXP (-SEARCH). In $GEMPAK/source/gemlib/oa/oawfsr.f, you see that the search radius SRAD is SEARCH * WEIGHT, eg: SRAD = SEARCH * [ 5.051457 * ( DELTAN * 2. / PI ) ** 2 ] as documented in the Koch reference. Steve Chiswell >From: address@hidden >Organization: UCAR/Unidata >Keywords: 200312311856.hBVIuPp2000555 >Hi- >(Happy Holidays!) >I have a question about search and radius from oabsfc and gdobscnt. >In search the units for the search radius are Kilometers? While in >gdobscnt the units are in meters. >I am attempting to see how many observations contribute to each grid point >from my surface file but don't know how to relate search to radius. >Can you provide any information that might help me? >I am currently using 20/EX for search and a radius of 60000 meters. >Thanks very much, > >-- >James Correia Jr. >Ph.D. Candidate in Agricultural Meteorology >Dept. of Agronomy, Iowa State University >********************************************* >Email: address@hidden >Phone: 515-294-5587 >Web: http://www.mesoscale.iastate.edu/jimmyc/ >********************************************* >"Imagination is more important than knowledge." >-Einstein > >"There is a difference between knowing the path and walking the path" >-"Morpheus" >