dset sfc.dat title NCEP sfc data options big_endian undef -.9999E+31 xdef 1 linear 1 1 ydef 37 levels -90.0 -85.0 -80.0 -75.0 -70.0 -65.0 -60.0 -55.0 -50.0 -45.0 -40.0 -35.0 -30.0 -25.0 -20.0 -15.0 -10.0 -5.0 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 65.0 70.0 75.0 80.0 85.0 90.0 zdef 1 linear 1 1 tdef 1 linear 15jan1000 1mo vars 1 sfc 0 99 zonal mean surface pressure endvars