Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 9/4/2009
Publication Date: 10/21/2009
Citation: Jackson, T.J., Bindlish, R., Cosh, M.H., Holmes, T.R., O'Neill, P. 2009. Soil moisture retrieval from Aquarius [abstract]. Aquarius Science Team Meeting. 2009 CDROM. Interpretive Summary:
Technical Abstract: Aquarius observations over land offer an unprecedented opportunity to provide a value-added product, land surface soil moisture, which will contribute to a better understanding of the Earth’s climate and water cycle. Additionally, Aquarius will provide the first spaceborne data that can be used to assess the synergy of L-band passive and active observations for improving remote sensing of soils and vegetation. The first stage of our research focuses on the radiometer data, due to its heritage in this application. This builds on soil moisture algorithms that are currently being used with AMSR-E observations. We will implement two different approaches. Both have been validated for AMSR-E and have been applied to aircraft and satellite L-band data. A unique component of Aquarius/SAC-D is the availability of a 36.5 GHz radiometer. Both retrieval approaches utilize this information to derive land surface temperature (LST), which is used to compute emissivity. In addition, the retrieved LST is another potential Aquarius/SAC-D product. Soil moisture and temperature products will be validated using established and well calibrated in situ observations. Satellite-based soil moisture products from AMSR-E and the SMOS mission will be used to assess the performance at the global scale. This validated soil moisture product would serve as a baseline for our further research on a combined passive-active soil moisture algorithm. It is anticipated that the active microwave observations would contribute to improvements in corrections for roughness and vegetation effects. Analysis of Aquarius observations over land will also contribute to radio frequency interference (RFI) studies and will provide an assessment of the sensor products in a range not covered by the oceans. The use of Aquarius observations in the early stages of the mission will contribute to establishing a longer term climate record of L-band brightness temperature and soil moisture when combined with SMAP.