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SRB Grid Geometry

The horizontal resolution of the NASA/GEWEX SRB parameters is, to a large degree, dictated by the resolution of the input data to the SRB models. The resulting SRB parameters are generated and available on a nested global grid, which contains 44016 cells. The initial grid has a resolution of 1° latitude globally, and a longitudinal resolution ranging from 1° in the tropics and subtropics to 120° at the poles. The first cell is bounded in latitude from 89°-90° South and by longitude from 0°-120° East. The cells start at the Greenwich meridian and proceed east around the globe, then shift one degree to the north. The number of cells per latitude band starting at the south pole are:

  
           3,  45,  45,  45,  45,  45,  45,  45,  45,  45,
          90,  90,  90,  90,  90,  90,  90,  90,  90,  90,
         180, 180, 180, 180, 180, 180, 180, 180, 180, 180,
         180, 180, 180, 180, 180, 180, 180, 180, 180, 180,
         180, 180, 180, 180, 180, 360, 360, 360, 360, 360,
         360, 360, 360, 360, 360, 360, 360, 360, 360, 360,
         360, 360, 360, 360, 360, 360, 360, 360, 360, 360,
         360, 360, 360, 360, 360, 360, 360, 360, 360, 360,
         360, 360, 360, 360, 360, 360, 360, 360, 360, 360,
         360, 360, 360, 360, 360, 360, 360, 360, 360, 360,
         360, 360, 360, 360, 360, 360, 360, 360, 360, 360,
         360, 360, 360, 360, 360, 360, 360, 360, 360, 360,
         360, 360, 360, 360, 360, 360, 360, 360, 360, 360,
         360, 360, 360, 360, 360, 180, 180, 180, 180, 180,
         180, 180, 180, 180, 180, 180, 180, 180, 180, 180,
         180, 180, 180, 180, 180, 180, 180, 180, 180, 180,
          90,  90,  90,  90,  90,  90,  90,  90,  90,  90,
          45,  45,  45,  45,  45,  45,  45,  45,  45,   3
Visual representation of SRB grid

The read software provided with each data file contains a subroutine to regrid the SRB parameters to a true 1° latitude by 1° longitude grid using replication at higher latitudes where the number of SRB cells per latitude band is less than 360.