Where can I get a value of region for a shell variable

Hello,
I'm hacking some shell scripts and would like to generate some files which
are named based on the current region. Is there a convenient way to get the
name of the current region into a shell variable.
Thanks,

               Joseph K. Vaughan
               University of Arizona
               Institute of Atmospheric Physics
               PAS Bldg, Rm 470
               Tucson, AZ 85721

I can also be reached by return mail on the internet or as
jkv@air.atmo.arizona.edu and by phone at 602/621-9663.