> I believe this FAQ answers exactly your question (with the same type of > data no less!) > > ../../faq/using-sigma-and-curvilinear-model-coordinates.htm BINGO! Looks great! Thanks muchly. The key is the redefintion of mp_phi and mp_lambda. Thanks! -- Gary Strand Climate Change Research Section, NCAR (303) 497-1336 strandwg@ucar.edu http://www.cgd.ucar.edu/ccr/strandwg