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ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Hydrology and Remote Sensing Laboratory » Research » Publications at this Location » Publication #384999

Research Project: Integrating Remote Sensing, Measurements and Modeling for Multi-Scale Assessment of Water Availability, Use, and Quality in Agroecosystems

Location: Hydrology and Remote Sensing Laboratory

Title: Validation of soil moisture data products from the NASA SMAP mission

item COLLIANDER, A. - Jet Propulsion Laboratory
item REICHLE, R. - National Aeronautics And Space Administration (NASA)
item Crow, Wade
item Cosh, Michael
item CHEN, F. - Science Systems And Applications, Inc
item CHAN, S. - Jet Propulsion Laboratory
item DAS, N. - Jet Propulsion Laboratory
item BINDLISH, R. - National Aeronautics And Space Administration (NASA)
item CHAUBELL, J. - Jet Propulsion Laboratory
item LIU, Q. - National Aeronautics And Space Administration (NASA)
item O'NEILL, P. - National Aeronautics And Space Administration (NASA) - Johnson Space Center
item DUNBAR, R. - Jet Propulsion Laboratory
item DANG, L. - Jet Propulsion Laboratory
item KIMBALL, J. - University Of Montana
item AL JASSAR, H. - Kuwait University
item ASANUMA, J. - University Of Tsukuba
item BHATTACHARYA, K. - Collaborator
item BERG, A. - University Of Guelph
item Bosch, David - Dave
item BOURGEAU-CHAVEZ, L. - Michigan Technological University
item CALDWELL, T. - Us Geological Survey (USGS)
item CALVERT, J. - Collaborator
item DORIGO, W. - Vienna University Of Technology
item Holifield Collins, Chandra
item JENSEN, K. - University Of Copenhagen
item Livingston, Stanley
item LOPEZ-BAEZA, E. - Valencia University
item MARTINEZ-FERNANDEZ, J. - Collaborator
item MCNAIRN, H. - Agriculture And Agri-Food Canada
item MOGHADDAM, M. - University Of Southern California
item MONTZKA, C. - Juelich Research Center
item NOTARNICOLA, C. - Collaborator
item PELLARIN, T. - Universite Grenoble Alpes
item Prueger, John
item PULLIAINEN, J. - Finnish Meteorological Institute
item RAMOS, J. - Universidad Nacianal Autonoma De Mexico
item Seyfried, Mark
item Starks, Patrick
item SU, Z. - University Of Twente
item THIBEAULT, M. - Collaborator
item WALKER, J. - Monash University
item ENTEKHABI, D. - Collaborator
item YUEH, S. - Jet Propulsion Laboratory

Submitted to: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/2/2021
Publication Date: 11/13/2021
Citation: Colliander, A. Reichle, R.H., Crow, W.T., Cosh, M.H., Chen, F., Chan, S., Das, N., Bindlish, R., Chaubell, M.J., Kim, S.B., Liu, Q., O’Neill, P., Dunbar, R.S., Dang, L., Kimball, J., Jackson, T.J., al Jassar, J.K., Asanuma, J., Bhattacharya, B.K., Berg, A., Bosch, D.D., Bourgeau-Chavez, L., Caldwell, T., Calvet, J-C., Dorigo, W., Holifield Collins, C., Jensen, K., Livingston, S., Lopez-Baeza, E., Martínez-Fernández, J., McNairn, H., Moghaddam, M., Montzka, C., Notarnicola, C., Pellarin, T., Prueger, J., Pulliainen, J., Ramos, J., Seyfried, M., Starks, P., Su, Z., van der Velde, R., Zeng, Y., Thibeault, M., Walker, J.P., Zribi, M., Entekhabi, D., and Yueh, S. 2022. Validation of Soil Moisture Data Products from the NASA SMAP Mission. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing. 15:364-392.

Interpretive Summary: Launched in 2015, the NASA Soil Moisture Active/Passive (SMAP) mission represents the culmination of over three decades of effort by USDA scientists to develop a viable approach for measuring soil moisture from space. Now that six years of SMAP data have been acquired, it is critical to assess the performance of the soil moisture estimates it generates and ensure that they are meeting accuracy requirements defined by key agricultural applications. This paper provides the most in-depth, and longest, such assessment of SMAP soil moisture products to date. By examining a range of validation sources - including intensive ground soil moisture networks operated by the USDA Agricultural Research Service - this paper demonstrates that SMAP soil moisture data products are generally meeting their pre launch accuracy goals. These results will further the operational use of SMAP data products for agricultural monitoring and management applications.

Technical Abstract: NASA’s Soil Moisture Active Passive (SMAP) mission has been conducting comprehensive validation of its soil moisture (SM) products since the start of data production on March 31, 2015. Prior to launch, the mission defined a set of criteria for core validation sites (CVS) that enable the testing of the key mission SM accuracy requirement (i.e., an average unbiased root-mean-square error across the CVS of less than 0.04 m^3/m^3). The validation approach also includes other (“sparse network”) in situ SM measurements, other global spaceborne SM products, global model-based SM products, and field experiments. Over the past six years, the SMAP SM products have been analyzed with respect to the reference data, and the analysis approaches themselves have been exposed to scrutiny in an effort to best understand the products’ performance. Validation of the most recent SMAP Level 2 and 3 SM retrieval products (R17000) shows that the radiometer-based SM continues to meet mission requirements. The radiometer-based retrieval product is generally consistent with SM retrievals from the ESA Soil Moisture Ocean Salinity mission, although there are differences in some regions. The high-resolution (3-km) retrieval product, generated by combining Copernicus Sentinel-1 data with SMAP radiometer observations, performs within expectations. Currently, however, there is limited availability of high-resolution (3-km) CVS reference data to enable extensive validation at this spatial scale. The most recent (version 5) SMAP Level 4 SM data assimilation product provides surface and root-zone SM with complete spatio-temporal coverage at 9-km resolution and also meets performance requirements. The SMAP SM validation program will continue as long as the mission is active; future plans include expanding it to forested and high-latitude regions.