This data set contains a series of land surface parameters simulated from the Noah 2.7.1 model in the Global Land Data Assimilation System (GLDAS). The data are in 1.0 degree resolution and range from 1979 to the present. The temporal resolution is monthly.
This simulation was forced by combination of NOAA/GDAS atmospheric analysis ... fields, spatially and temporally disaggregated NOAA Climate Prediction Center Merged Analysis of Precipitation (CMAP) fields, and observation based downward shortwave and longwave radiation fields derived using the method of the Air Force Weather Agency's AGRicultural METeorological modeling system (AGRMET).
The simulation was initialized on 1 January 1979 using soil moisture and other state fields from a GLDAS/Noah model climatology for that day of the year.
WGRIB or other GRIB reader is required to read the files. The data set applies a user-defined parameter table to indicate the contents and parameter number. The following table shows a list of parameters, their Product Definition Section (PDS) IDs and units.
PDS_IDs Full_Name Unit
1 Surface pressure Pa
11 Near surface air temperature K
32 Near surface wind magnitude m/s
51 Near surface specific humidity kg/kg
57 Total Evapotranspiration kg/m^2/s
65 Snow Water Equivalent kg/m^2
71 Total canopy water storage kg/m^2
85 Average layer soil temperature K
86 Average layer soil moisture kg/m^2
99 Snowmelt kg/m^2/s
111 Net Shortwave Radiation W/m^2
112 Net Longwave Radiation W/m^2
121 Latent Heat Flux W/m^2
122 Sensible Heat Flux W/m^2
131 Snowfall rate kg/m^2/s
132 Rainfall rate kg/m^2/s
138 Average Surface Temperature K
155 Ground Heat Flux W/m^2
204 Surface incident shortwave radiation W/m^2
205 Surface incident longwave radiation W/m^2
234 Subsurface Runoff kg/m^2/s
235 Surface Runoff kg/m^2/s
There are 4 vertical levels for the Soil Moisture (PDS 086) in the GRIB file. For more information, please see