Global spectral medium range weather forecasting model on PARAM

This paper describes the experience gained while parallelizing the global medium range weather forecasting application called T80 on a PARAM machine based on a distributed memory parallel architecture. The T80 code employs the spectral method for horizontal directions and finite differencing in the vertical direction and time marching. The parallel implementation takes care of the easy portability of parallel code across various platforms and environments. The parallel code is optimized using i860 based assembly routines. The validation of the parallel code has been accomplished by comparing the parallel T80 results with those of the Gray for 2(nd) February 1993 initial data.