JM is "#undef OLD_GRID_IO" needed in ini_curvilinear_grid.F ? Seems to work fine without it and it's not very convenient to use tilexxx.mitgrid for a domain that's not cube-sphere D. -- Dimitris Menemenlis <menemenlis at sbcglobal.net> 5056 Oakwood Ave, La Canada, CA 91011-2450 tel/fax: 818-790-6735; cell: 626-644-1928