The following table is based on that given in WMO publication no. 306 - Manual on Codes. The information is believed to be correct. However, the definitions in the WMO manual may be liable to change over time. If there is a difference between the information here and in the WMO manual, the WMO manual is the definitive source.

WMO Code Table 6 - data representation type

Value Meaning gridType
Comment
0 Latitude/longitude grid - equidistant cylindrical or Plate Carree projection projection regular_ll
reduced_ll
- regular_gg for ksec2(17)=0
- reduced_gg for ksec2(17)=1
1 Mercator projection mercator
2 Gnomonic projection

3 Lambert conformal, secant or tangent, conical orbipolar, projection lambert
4 Gaussian latitude/longitude grid regular_gg
reduced_gg
- regular_gg for ksec2(17)=0
- reduced_gg for ksec2(17)=1
5 Polar stereographic projection polar_stereographic
6 Universal Transverse Mercator (UTM) projection UTM
7 Simple polyconic projection simple_polyconic
8 Albers equal-area, secant or tangent, conic or bi-polar, projection

9 Miller's cylindrical projection

10 Rotated latitude/longitude grid rotated_ll
11- 12 Reserved

13 Oblique Lambert conformal, secant or tangent, conical or bipolar, projection

14 Rotated gaussian latitude/longitude grid rotated_gg
15 - 19 Reserved

20 Stretched latitude/longitude grid stretched_ll
21 - 23 Reserved

24 Stretched gaussian latitude/longitude grid stretched_gg
25 - 29 Reserved

30 Stretched and rotated latitude/longitude grid stretched_rotated_ll
31 - 33 Reserved

34 Stretched and rotated gaussian latitude/longitude grid stretched_rotated_gg
35 - 49 Reserved

50 Spherical harmonic coefficients sh
51 - 59 Reserved

60 Rotated spherical harmonic coefficients rotated_sh
61 - 69 Reserved

70 Stretched spherical harmonic coefficients stretched_sh
71 - 79 Reserved

80 Stretched and rotated spherical harmonic coefficients stretched_rotated_sh
81 - 89 Reserved

90 Space view, perspective or orthographic space_view
91 - 191 Reserved

192 ECMWF ocean data

193 - 254 Reserved for local use