ElementContentsecCodes keys
1Data representation type (see WMO code table 6) = 4gridType
2Not specified for quasi-regular (reduced) grids.
3Number of points along a meridian (Nj).Nj
Ny
4Latitude of the first grid point, La1.latitudeOfFirstGridPointInDegrees*1000
5Longitude of the first grid point, Lo1.longitudeOfFirstGridPointInDegrees*1000
6Resolution flag, = 0 (direction increments not given)ijDirectionIncrementGiven*128
7Latitude of the last grid point, La2.latitudeOfLastGridPointInDegrees*1000
8Longitude of the last grid point, Lo2.longitudeOfLastGridPointInDegrees*1000
9i direction increment. Cannot be used for quasi-regular (reduced) grids.iDirectionIncrementInDegrees*1000
10Number of parallels between a pole and the Equator,ie the gaussian grid number.numberOfParallelsBetweenAPoleAndTheEquator
11Scanning mode flags (see WMO code table 8)

iScansNegatively

jScansNegatively

jPointsAreConsecutive

12Number of vertical coordinate parameters.NV
13Latitude of the southern pole of rotation.latitudeOfSouthernPoleInDegrees*1000
14Longitude of the southern pole of rotation.longitudeOfSouthernPoleInDegrees*1000
15Latitude of the pole of stretching.latitudeOfPoleOfStretchingInDegrees *1000
16Longitude of the pole of stretching.longitudeOfPoleOfStretchingInDegrees *1000
171 = quasi-regular (reduced) grid.gridType
18
Earth flag:
 0      Earth assumed spherical with radius 6367.47 km.
 64     Earth assumed oblate spheroidal with size as determined by IAU in 1965:
        6378.160km,   6356.775km,   f=1/297.0
earthIsOblate
19
Components flag.
 0      Resolved u and v components of vector quantities relative to easterly
        and northerly directions; or not used.
 8      Resolved u and v components of vector quantities relative to the
        defined grid in the direction of increasing x and y (or i and j)
        coordinates respectively.
uvRelativeToGrid
20-22Reserved. Set to 0.
23-nnNN, the number of points along a full parallel (360 degrees) is defined for each latitude row in the sub-area. The number of parallels is given by Nj above.
See the algorithm below for calculating the actual number of points along each sub-area latitude row (ECMWF convention).		pl

The number of points Np within a subarea along a parallel of a reduced grid can be obtained as:

   Np = [(Loe-Low)/Res] + 1
   
 where:

   Loe    = Lo2
   Res    = 360000/NN
   If Mod(Lo1/Res,1.0) = 0,
     Incr = 0
   otherwise
     Incr = 1
   Ninter = [Lo1/Res] + Incr                    
   Low    = Ninter*Res       ; Low -> (Low - 360000) if Lo2 is less then Lo1.