GRIB2 - GRID DEFINITION TEMPLATE 3.31

Albers equal area

Created 07/29/2005


Octet No. Contents
15
Shape of the Earth (See Code Table 3.2)
16
Scale factor of radius of spherical Earth
17-20
Scale value of radius of spherical Earth
21
Scale factor of major axis of oblate spheroid Earth
22-25
Scaled value of major axis of oblate spheroid Earth
26
Scale factor of minor axis of oblate spheroid Earth
27-30
Scaled value of minor axis of oblate spheroid Earth
31-34
Nx ― number of points along the x-axis
35-38

Ny — number of points along the y-axis

39-42
La1― latitude of first grid point
43-46
Lo1― longitude of first grid point
47

Resolution and component flags (see Flag Table 3.3)

48-51
LaD ― latitude where Dx and Dy are specified
52-55
LoV ― longitude of meridian parallel to y-axis along which latitude increases as the y-coordinate increases
56-59

Dx ― x-direction grid length (see Note 1)     

60-63

Dy ― y-direction grid length (see Note 1)

64

Projection centre flag (see Flag Table 3.5)

65 Scanning mode (flags ― see Flag Table 3.4)
66-69
Latin 1 ― first latitude from the pole at which the secant cone cuts the sphere
70-73
Latin 2 ― second latitude from the pole at which the secant cone cuts the sphere
74-77
Latitude of the southern pole of projection
78-81
Longitude of the southern pole of projection


Notes:

1. Grid lengths are in units on 10-3 m, at the latitude specified by LaD.

2.  If  Latin 1 = Latin 2, then the projection is on a tangent cone.

3.  The resolution flags (bits 3-4 of Flag Table 3.3) are not applicable.

3.  LoV is the longitude value of the meridian which is parallel to the y-axis (or columns of the grid) along
along which latitude increases as the y-coordinate increase (the orientation longitude may or may not
appear on a particular grid).

5.  A scale 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.


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