NLDAS Secondary Forcing Data L4 Hourly 0.125 x 0.125 degree V2.0 (NLDAS_FORB0125_H) at GES DISC

This data set contains the secondary forcing hourly data "File B" for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing and range from Jan 1979 to the present. The temporal resolution is hourly. The file format isnetCDF (converted from the GRIB data files). The non-precipitation land surface forcing fields for NLDAS-2 are derived from the analysis fields of the NCEP North American Regional Reanalysis (NARR). NARR analysis fields are 32-km spatial resolution and 3-hourly temporal frequency. Those NARR fields that are utilized to generate NLDAS-2 forcing fields are spatially interpolated to the finer resolution of the NLDAS 1/8th-degree grid and then temporally disaggregated to the NLDAS hourly frequency. NLDAS-2 is providing a second forcing file, "File B", in which the surface temperature, humidity, and wind fields are represented not at 2-meters and 10-meters above the height of the NLDAS terrain, but rather at the same height above the NLDAS terrain as the height above the NARR terrain of the lowest prognostic level of the NARR assimilation system (namely, the same height above the model terrain as the lowest prognostic level of the mesoscale Eta model, which is the assimilating model in NARR). The surface downward surface radiation field in "File B" is taken directly from NARR, without any bias correction. The precipitation and convective precipitation fields in "File B" are also taken directly from NARR, and are used to calculate the convective fraction provided in "File A". The aerodynamic conductance is "File B" is also taken from NARR. The hourly land surface forcing fields for NLDAS-2 are grouped into two files, "File A" and "File B". "File B" is the secondary (optional) forcing file and contains ten meteorological forcing fields. Details about the generation of the NLDAS-2 forcing datasets can be found in Xia et al. (2012).

Data and Resources

Additional Info

Field Value
Maintainer Earthdata Forum
Last Updated April 13, 2026, 20:11 (UTC)
Created April 1, 2025, 18:03 (UTC)
accessLevel public
bureauCode {026:00}
catalog_conformsTo https://project-open-data.cio.gov/v1.1/schema
harvest_object_id 38664386-7db1-4292-84f4-caa44bc55d5c
harvest_source_id b99e41c6-fe79-4c19-bbc3-9b6c8111bfac
harvest_source_title Science Discovery Engine
identifier 10.5067/96S0R3LFOBTU
license https://www.usa.gov/government-works
modified 2026-04-06T22:16:01Z
programCode {026:000}
publisher NASA/GSFC/SED/ESD/TISL/GESDISC
resource-type Dataset
source_datajson_identifier true
source_hash a1870dfcd72a427d306f175e9cccd55621a74fbbc9924f4593676cb245da293a
source_schema_version 1.1
spatial ["CARTESIAN",[{"WestBoundingCoordinate":-125,"NorthBoundingCoordinate":53,"EastBoundingCoordinate":-67,"SouthBoundingCoordinate":25}]]
temporal 1979-01-01/2026-04-06
theme {"Earth Science"}