Global retrieval of surface soil moisture using L-band SMAP SAR data and its validation

S. Kim, J. Johnson, Majid Moghaddam, Leung Tsang, J. Van Zyl, A. Colliander, S. Dunbar, T. Jackson, Sermsak Jaruwatanadilok, R. West, Aaron A Berg, T. Caldwell, M. Cosh, E. Lopez-Baeza, M. Thibeault, J. Walker, Dara Entekhabi, S. Yueh

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Surface soil moisture retrievals using radar observations have been challenging due to the strong effects by surfac roughness and vegetation scattering. Physically-based forward models for radar scattering are inverted using time-serie retrieval algorithm to systematically correct for the effect of the roughness and vegetation. The retrievals are performed for top 5-cm layer soil moisture at 3-km spatial resolution using the L-band radar data acquired by the Soil Moisture Activ Passive (SMAP) satellite globally every three days from mid-April to early July, 2015. These were assessed over 1 rigorously-chosen core validation sites covering a wide range of biomass types and amounts and soil conditions. The soi moisture retrieval performance had an accuracy of approaching the goal of 0.063 m3/m3 unbiased-RMSE (root mean squar error), a near zero bias, and a correlation of 0.56. The successful retrieval demonstrates that the physically-based retrieva method is capable of characterizing soil moisture over diverse conditions of soil moisture, surface roughness, and vegetatio on a global scale.

Original languageEnglish
Title of host publicationProceedings of the 11th European Conference on Synthetic Aperture Radar, EUSAR 2016
Subtitle of host publicationHamburg, Germany; 6-9 June 2016
Place of PublicationPiscataway NJ USA
PublisherIEEE, Institute of Electrical and Electronics Engineers
Number of pages4
ISBN (Electronic)9783800742288
Publication statusPublished - 2016
EventEuropean Conference on Synthetic Aperture Radar (EUSAR) 2016 - Hamburg, Germany
Duration: 6 Jun 20169 Jun 2016
Conference number: 11th (Proceedings)


ConferenceEuropean Conference on Synthetic Aperture Radar (EUSAR) 2016
Abbreviated titleEUSAR 2016
Internet address

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