ifs-grid-shifted.grib2 centre paramId shortName units name ecmf 136 tcw kg m**-2 Total column water ecmf 260360 sot K Soil temperature ecmf 133 q kg kg**-1 Specific humidity ecmf 168 2d K 2 metre dewpoint temperature ecmf 169 ssrd J m**-2 Surface short-wave (solar) radiation downwards ecmf 137 tcwv kg m**-2 Total column vertically-integrated water vapour ecmf 260015 ptype (Code table 4.201) Precipitation type ecmf 260360 sot K Soil temperature ecmf 260360 sot K Soil temperature ecmf 260048 tprate kg m**-2 s**-1 Total precipitation rate ecmf 172 lsm (0 - 1) Land-sea mask ecmf 32 asn (0 - 1) Snow albedo ecmf 33 rsn kg m**-3 Snow density ecmf 135 w Pa s**-1 Vertical velocity ecmf 262000 sithick m Sea ice thickness ecmf 260199 vsw m**3 m**-3 Volumetric soil moisture ecmf 175 strd J m**-2 Surface long-wave (thermal) radiation downwards ecmf 132 v m s**-1 V component of wind ecmf 176 ssr J m**-2 Surface net short-wave (solar) radiation ecmf 131 u m s**-1 U component of wind ecmf 157 r % Relative humidity ecmf 138 vo s**-1 Vorticity (relative) ecmf 138 vo s**-1 Vorticity (relative) ecmf 260199 vsw m**3 m**-3 Volumetric soil moisture ecmf 156 gh gpm Geopotential height ecmf 156 gh gpm Geopotential height ecmf 177 str J m**-2 Surface net long-wave (thermal) radiation ecmf 260199 vsw m**3 m**-3 Volumetric soil moisture ecmf 179 ttr J m**-2 Top net long-wave (thermal) radiation ecmf 155 d s**-1 Divergence ecmf 155 d s**-1 Divergence ecmf 260199 vsw m**3 m**-3 Volumetric soil moisture ecmf 156 gh gpm Geopotential height ecmf 130 t K Temperature ecmf 130 t K Temperature ecmf 180 ewss N m**-2 s Time-integrated eastward turbulent surface stress ecmf 132 v m s**-1 V component of wind ecmf 49 10fg m s**-1 Maximum 10 metre wind gust since previous post-processing ecmf 181 nsss N m**-2 s Time-integrated northward turbulent surface stress ecmf 157 r % Relative humidity ecmf 131 u m s**-1 U component of wind ecmf 157 r % Relative humidity ecmf 133 q kg kg**-1 Specific humidity ecmf 133 q kg kg**-1 Specific humidity ecmf 130 t K Temperature ecmf 260360 sot K Soil temperature ecmf 135 w Pa s**-1 Vertical velocity ecmf 135 w Pa s**-1 Vertical velocity ecmf 133 q kg kg**-1 Specific humidity ecmf 205 ro m Runoff ecmf 132 v m s**-1 V component of wind ecmf 156 gh gpm Geopotential height ecmf 131 u m s**-1 U component of wind ecmf 141 sd m of water equivalent Snow depth ecmf 131 u m s**-1 U component of wind ecmf 228 tp m Total precipitation ecmf 132 v m s**-1 V component of wind ecmf 138 vo s**-1 Vorticity (relative) ecmf 144 sf m of water equivalent Snowfall ecmf 138 vo s**-1 Vorticity (relative) ecmf 135 w Pa s**-1 Vertical velocity ecmf 201 mx2t K Maximum temperature at 2 metres since previous post-processing ecmf 130 t K Temperature ecmf 151 msl Pa Mean sea level pressure ecmf 202 mn2t K Minimum temperature at 2 metres since previous post-processing ecmf 156 gh gpm Geopotential height ecmf 155 d s**-1 Divergence ecmf 156 gh gpm Geopotential height ecmf 155 d s**-1 Divergence ecmf 262140 sve m s**-1 Eastward surface sea water velocity ecmf 133 q kg kg**-1 Specific humidity ecmf 138 vo s**-1 Vorticity (relative) ecmf 262139 svn m s**-1 Northward surface sea water velocity ecmf 0 unknown unknown unknown ecmf 157 r % Relative humidity ecmf 157 r % Relative humidity ecmf 135 w Pa s**-1 Vertical velocity ecmf 155 d s**-1 Divergence ecmf 130 t K Temperature ecmf 130 t K Temperature ecmf 228246 100u m s**-1 100 metre U wind component ecmf 262124 zos m Sea surface height ecmf 228247 100v m s**-1 100 metre V wind component ecmf 133 q kg kg**-1 Specific humidity ecmf 133 q kg kg**-1 Specific humidity ecmf 138 vo s**-1 Vorticity (relative) ecmf 157 r % Relative humidity ecmf 160 sdor m Standard deviation of sub-gridscale orography ecmf 132 v m s**-1 V component of wind ecmf 131 u m s**-1 U component of wind ecmf 235 skt K Skin temperature ecmf 131 u m s**-1 U component of wind ecmf 132 v m s**-1 V component of wind ecmf 135 w Pa s**-1 Vertical velocity ecmf 135 w Pa s**-1 Vertical velocity ecmf 163 slor Numeric Slope of sub-gridscale orography ecmf 155 d s**-1 Divergence ecmf 164 tcc (0 - 1) Total cloud cover ecmf 131 u m s**-1 U component of wind ecmf 132 v m s**-1 V component of wind ecmf 138 vo s**-1 Vorticity (relative) ecmf 138 vo s**-1 Vorticity (relative) ecmf 156 gh gpm Geopotential height ecmf 156 gh gpm Geopotential height ecmf 157 r % Relative humidity ecmf 165 10u m s**-1 10 metre U wind component ecmf 155 d s**-1 Divergence ecmf 156 gh gpm Geopotential height ecmf 166 10v m s**-1 10 metre V wind component ecmf 130 t K Temperature ecmf 155 d s**-1 Divergence ecmf 130 t K Temperature ecmf 132 v m s**-1 V component of wind ecmf 167 2t K 2 metre temperature ecmf 131 u m s**-1 U component of wind ecmf 157 r % Relative humidity ecmf 133 q kg kg**-1 Specific humidity ecmf 133 q kg kg**-1 Specific humidity ecmf 157 r % Relative humidity ecmf 130 t K Temperature ecmf 133 q kg kg**-1 Specific humidity ecmf 135 w Pa s**-1 Vertical velocity ecmf 135 w Pa s**-1 Vertical velocity ecmf 156 gh gpm Geopotential height ecmf 131 u m s**-1 U component of wind ecmf 132 v m s**-1 V component of wind ecmf 131 u m s**-1 U component of wind ecmf 135 w Pa s**-1 Vertical velocity ecmf 138 vo s**-1 Vorticity (relative) ecmf 132 v m s**-1 V component of wind ecmf 138 vo s**-1 Vorticity (relative) ecmf 130 t K Temperature ecmf 155 d s**-1 Divergence ecmf 138 vo s**-1 Vorticity (relative) ecmf 156 gh gpm Geopotential height ecmf 155 d s**-1 Divergence ecmf 156 gh gpm Geopotential height ecmf 133 q kg kg**-1 Specific humidity ecmf 157 r % Relative humidity ecmf 155 d s**-1 Divergence ecmf 130 t K Temperature ecmf 157 r % Relative humidity ecmf 135 w Pa s**-1 Vertical velocity ecmf 130 t K Temperature ecmf 133 q kg kg**-1 Specific humidity ecmf 157 r % Relative humidity ecmf 133 q kg kg**-1 Specific humidity ecmf 131 u m s**-1 U component of wind ecmf 138 vo s**-1 Vorticity (relative) ecmf 135 w Pa s**-1 Vertical velocity ecmf 132 v m s**-1 V component of wind ecmf 131 u m s**-1 U component of wind ecmf 132 v m s**-1 V component of wind ecmf 135 w Pa s**-1 Vertical velocity ecmf 155 d s**-1 Divergence ecmf 129 z m**2 s**-2 Geopotential ecmf 132 v m s**-1 V component of wind ecmf 156 gh gpm Geopotential height ecmf 131 u m s**-1 U component of wind ecmf 138 vo s**-1 Vorticity (relative) ecmf 134 sp Pa Surface pressure ecmf 157 r % Relative humidity ecmf 155 d s**-1 Divergence ecmf 130 t K Temperature 164 of 164 messages in ifs-grid-shifted.grib2
ungrib - grib edition num 2 reading from grib file = ifs-grid-shifted.grib2 ECMWF --------------------------------------------------------------------------------------- rec Prod Cat Param Lvl Lvl Lvl Prod Name Time Fcst num Disc num code one two Templ hour ---------------------------------------------------------------------------------------
In meteorological GRIB files, HGT and GEOPT both represent the vertical height of a given atmospheric layer, but they are encoded in different mathematical units and formats.
Parameter
Name
Variable Description
Unit
Common Application
HGT
Geopotential Height
The height of a pressure surface above mean sea level.
\(\text{gpm}\) (geopotential meters) or \(\text{m}\)
The gravitational potential energy per unit mass at a specific location.
\(\text{m}^2\text{ s}^{-2}\)
Raw model output data; used as surface orography in dynamic modeling.
You can easily convert between the two using the Earth's standard gravitational acceleration (\(g = 9.80665 \text{ m s}^{-2}\)):
\[HGT = \frac{GEOPT}{g}\]
Practical Use in GRIB Data
If you are extracting GEOPT (e.g., from an ECMWF invariant GRIB file), you will need to divide the grid values by \(9.80665\) to get the physical altitude in meters required by weather models like WRF.
If you are analyzing HGT, the values are already practically identical to geometric meters, making them immediately readable for overlaying on weather maps.
SOILGEO and SOILHGT
SOILGEO and SOILHGT represent the surface orography (the elevation of the ground/terrain) at the bottom boundary of weather models, mirroring the exact relationship between GEOPT and HGT.
SOILGEO (Surface Geopotential): The gravitational potential energy per unit mass at surface terrain level. It is encoded in \(\text{m}^2\text{ s}^{-2}\). This corresponds to the standard ECMWF variable parameter Z (Geopotential) extracted explicitly from an "invariant" surface file.
SOILHGT (Terrain / Surface Height): The physical altitude of the ground surface above mean sea level. It is encoded in geometric meters (\(\text{m}\)).
Just like free-atmosphere profiles, the two variables are linked strictly by the standard gravity of Earth (\(g = 9.80665 \text{ m s}^{-2}\)): \(\text{SOILHGT} = \frac{\text{SOILGEO}}{9.80665}\)