WLDAS

Dataset:

Western Land Data Assimilation System

Description:

The Western Land Data Assimilation System (WLDAS), developed at Goddard Space Flight Center (GSFC) and funded by the NASA Western Water Applications Office, provides water managers and stakeholders in the western United States with a long-term record of near-surface hydrology for use in drought assessment and water resources planning. WLDAS leverages advanced capabilities in land surface modeling and data assimilation to furnish a system that is customized for stakeholders’ needs in the region. We currently partner with the State Water Resources Control Board in California and the Colorado Climate Center.

WLDAS uses NASA’s Land Information System (LIS) to configure and drive the Noah Multiparameterization (Noah-MP) Land Surface Model to simulate land surface states and fluxes. Satellite data are used to parameterize and force the model and are also integrated using data assimilation. Our partners are active in evaluating model performance.

WLDAS uses meteorological observables including precipitation, incoming shortwave and longwave radiation, near surface air temperature, humidity, wind speed, and surface pressure along with parameters such as vegetation class, soil texture, and elevation as inputs to a model that simulates land surface the energy and water budget processes. Outputs of the model include soil moisture, snow depth and snow water equivalent, evapotranspiration, soil temperature, as well as derived quantities such as groundwater recharge and anomalies of the state variables.

Organization: Land Data Assimilation System

Website: https://ldas.gsfc.nasa.gov/wldas

Google Earth Engine Catalog: N/A

Spatial Resolution: 1113-m (0.01-deg)

Time Span: 1980-01-01 to present

Variables:

Soil Moisture 0-10 cm
Soil Moisture 10-40 cm
Soil Moisture 40-100 cm
Soil Moisture 100-200 cm
Soil Temperature 0-10 cm
Soil Temperature 10-40 cm
Soil Temperature 40-100 cm
Soil Temperature 100-200 cm
Snowmelt
Snow Water Equivalent
Snow Depth
Snow Sublimation
Surface Snow Area Fraction
Total Evapotranspiration
Surface Runoff Amount
Subsurface Runoff Amount
Surface Net Downward Longwave Flux
Surface Net Downward Shortwave Flux
Surface Upward Latent Heat Flux
Surface Upward Sensible Heat Flux
Downward Heat Flux in Soil
Snowfall Rate
Precipitation Rate
Water Table Depth
Terrestrial Water Storage
Groundwater Storage
Wind Speed
Air Temperature
Specific Humidity
Surface Pressure
Surface Downwelling Shortwave Flux in Air
ASCE Grass Reference ET
ASCE Alfalfa Reference ET

Terms of Use:

Distribution of data from the Goddard Earth Sciences Data and Information Services Center (GES DISC) is funded by NASA's Science Mission Directorate (SMD). Consistent with NASA Earth Science Data and Information Policy, data from the GES DISC archive are available free to the user community. For more information visit the GES DISC Data Policy page.

References:

Erlingis, J.M., M. Rodell, C.D. Peters-Lidard, B. Li, S.V. Kumar, J.S. Famiglietti, S.L. Granger, J.V. Hurley, P.-W. Liu, and D.M. Mocko. 2021. " A High-Resolution Land Data Assimilation System Optimized for the Western United States." Journal of the American Water Resources Association 57(5): 692–710. https://doi.org/10.1111/1752-1688.12910.