4       SUBROUTINE  grad(klevel, pg,pgx,pgy )
 
   17 #include "dimensions.h" 
   28       pgx( ij,l ) = pg( ij +1,l ) - pg( ij,l )
 
   35       pgx( ij,l ) = pgx( ij -
iim,l )
 
   39       pgy( ij,l ) = pg( ij,l ) - pg( ij +iip1,l )
 
subroutine grad(klevel, pg, pgx, pgy)
 
!$Header llmm1 INTEGER ip1jmp1
 
!$Header llmm1 INTEGER ip1jm
 
c c zjulian c cym CALL iim cym klev iim