Land/Sea Mask in the RTG_SST_HR analysis

The RTG_SST_HR analysis is done over all ocean areas, the Great Lakes, and any other inland bodies of water resolved by the land-sea mask. There is no analysis over land. The land values are filled by a Cressman interpolation to produce a complete grid for possible interpolation to other grids. The ocean and land areas are defined by a land sea mask. This data set is an ASCII file, ls.dat, which may be found at the FTP site:

ftp://polar.ncep.noaa.gov/pub/history/sst/rtg_high_res/lsmask

The spatial grid is defined identically to the grid for the SST arrays, with indices starting just east of the Greenwich Meridian and near the South Pole. The values in ls.dat are set to 0 over the ocean and 3 over land. It can be read by the following Fortran code:

DIMENSION LS(4320,2160)
OPEN (11,FILE='ls.dat')

C
C Read in land sea tags (0 for ocean; 3 for land)
C

READ (11,'(80I1)') LS
STOP
END