Section - Template 3 : Stretched and Rotated Latitude/longitude (or equidistant cylindrical, or Plate Carree)

Octets Key Type Content
15 shapeOfTheEarth codetable Shape of the earth (see Code Table 3.2)
16 scaleFactorOfRadiusOfSphericalEarth unsigned Scale factor of radius of spherical earth
17-20 scaledValueOfRadiusOfSphericalEarth unsigned Scaled value of radius of spherical earth
21 scaleFactorOfEarthMajorAxis unsigned Scale factor of major axis of oblate spheroid earth
22-25 scaledValueOfEarthMajorAxis unsigned Scaled value of major axis of oblate spheroid earth
26 scaleFactorOfEarthMinorAxis unsigned Scale factor of minor axis of oblate spheroid earth
27-30 scaledValueOfEarthMinorAxis unsigned Scaled value of minor axis of oblate spheroid earth
31-34 Ni unsigned Ni - number of points along a parallel
35-38 Nj unsigned Nj - number of points along a meridian
39-42 basicAngleOfTheInitialProductionDomain unsigned Basic angle of the initial production domain (see Note 1)
43-46 subdivisionsOfBasicAngle unsigned Subdivisions of basic angle used to define extreme longitudes and latitudes, and direction increments (see Note 1)
47-50 latitudeOfFirstGridPoint signed La1 - latitude of first grid point (see Note 1)
51-54 longitudeOfFirstGridPoint signed Lo1 - longitude of first grid point (see Note 1)
55 resolutionAndComponentFlags codeflag Resolution and component flags (see Flag Table 3.3)
56-59 latitudeOfLastGridPoint signed La2 - latitude of last grid point (see Note 1)
60-63 longitudeOfLastGridPoint signed Lo2 - longitude of last grid point (see Note 1)
64-67 iDirectionIncrement unsigned Di - i direction increment (see Notes 1 and 5)
68-71 jDirectionIncrement unsigned Dj - j direction increment (see Notes 1 and 5)
72 scanningMode codeflag Scanning mode (flags - see Flag Table 3.4)
73-nn pl unsigned List of number of points along each meridian or parallel (These octets are only present for quasi-regular grids as described in notes 2 and 3)
Notes:

( 1) Basic angle of the initial production domain and subdivisions of this basic angle are provided to manage cases where the recommended unit of 10-6 degrees is not applicable to describe the extreme longitudes and latitudes, and direction increments. For these last six descriptors, unit is equal to the ratio of the basic angle and the subdivisions number. For ordinary cases, zero and missing values should be coded, equivalent to respective values of 1 and 106 (10-6 degrees unit).

( 2) For data on a quasi-regular grid, where all the rows or columns do not necessarily have the same number of grid points, either Ni (Octets 31-34) or Nj (Octets 35-38) and the corresponding Di (Octets 64-67) or Dj (Octets 68-71) shall be coded with all bits set to 1 (missing). The actual number of points along each parallel or meridian shall be coded in the octets immediately following the Grid Definition Template (Octets [xx+1] - nn), as described in the description of the Grid Definition Section.

( 3) A quasi-regular grid is only defined for appropriate grid scanning modes. Either rows or columns, but not both simultaneously, may have variable numbers of points or variable spacing. The first point in each row (column) shall be positioned at the meridian (parallel) indicated by Octets 47-54. The grid points shall be evenly spaced in latitude (longitude).

( 4) A scaled value of radius of spherical Earth, or major or minor axis of oblate spheroid Earth is derived from applying appropriate scale factor to the value expressed in metres.

( 5) It is recommended to use unsigned direction increments

( 6) In most cases, multiplying Ni (octets 31–34) by Nj (octets 35–38) yields the total number of points in the grid. However, this may not be true if bit 8 of the scanning mode flags (octet 72) is set to 1