surface area measurements

[mosesm at MAIL.FWS.GOV]

     I am seeking information regarding the use of 1:24,000 DEMs to 
     calculate (approximate!?!) actual surface area in a topologically 
     diverse region.
     
     I am especially interested in any GRASS scripts, dot commands, methods
     ect. which would provide surface area estimates instead of planimetric
     area values.
     
     I am also searching for any work which analyzed the differences in 
     surface area estimation that result when 1:250,000 DMAs are used 
     instead of 1:24,000 DEMs in a region of substantial topographic 
     relief. 
     
    
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     Mike Moses
     National Biological Survey
     4512 McMurray Ave.
     Ft. Collins, CO  80525
     ph: (303) 226-9266
     fax: (303) 226-9230
     email: mosesm at mail.fws.gov
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