calculate areas on a globe

[Karen Bice <kbice@xxxxxxxx>]

This must be something that is easy to do, so I apologize for needing to
ask:

I have a gridded (lat, long) global data set of values (integers 1-25).
I want to calculate the TOTAL AREA (km^2) that has a value of 1, the
TOTAL AREA that has a value of 2, u.s.w.

This sounds like something for which there must be a Ferret function or
script. How can I do this? I am using v. 4.9.2 on an IRIX workstation.

Thanks. Karen


-- 
Karen L. Bice, Assistant Scientist		Mail Stop #23
Dept. of Geology and Geophysics			phone: (508) 289-3320
Woods Hole Oceanographic Institution		FAX:   (508) 457-2187
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