HR: 0800h
AN: H31D-0630    [Abstracts]
TI: Vegetation Water Content Retrievals for NAFE06 and CLASIC
AU: * McKee, L
EM: lynn.mckee@ars.usda.gov
AF: USDA ARS Hydrology and Remote Sensing Lab, Room 104, Bldg 007, BARC-W, 10300 Baltimore Av, Beltsville, MD 20705, United States
AU: Jackson, T J
EM: tom.jackson@ars.usda.gov
AF: USDA ARS Hydrology and Remote Sensing Lab, Room 104, Bldg 007, BARC-W, 10300 Baltimore Av, Beltsville, MD 20705, United States
AU: Bindlish, R
EM: rajat.bindlish@ars.usda.gov
AF: USDA ARS Hydrology and Remote Sensing Lab, Room 104, Bldg 007, BARC-W, 10300 Baltimore Av, Beltsville, MD 20705, United States
AU: Tao, J
EM: jing.tao@ars.usda.gov
AF: USDA ARS Hydrology and Remote Sensing Lab, Room 104, Bldg 007, BARC-W, 10300 Baltimore Av, Beltsville, MD 20705, United States
AB: Vegetation water content (VWC) is a valuable input to many microwave based soil moisture retrieval algorithms. Previous research, both theoretical and experimental, has established that VWC can be estimated using multispectral remote sensing. There are limits on the reliability of these methods that are related to canopy characteristics. For some crops index based techniques typically saturate before peak VWC occurs. Therefore, a careful evaluation using validation data is useful, especially in an intensive field campaign. As part of NAFE06 and CLASIC, ground based VWC sampling was conducted in conjunction with surface reflectance and Leaf Area Index (LAI) measurements. These data were used to establish crop/cover condition dependent relationships between the Normalized Difference Water Index (NDWI) and VWC. In order to apply these relationships over larger regions it was also necessary to develop land cover classifications using satellite data that incorporated the temporal changes that occurred during the study (i.e. flooding of rice fields). This was accomplished using multiple Landsat Thematic Mapper or ASTER images and a decision tree classifier. The NDWI relationships were applied to the available vegetation index images to generate VWC.
DE: 1800 HYDROLOGY
DE: 1843 Land/atmosphere interactions (1218, 1631, 3322)
DE: 1855 Remote sensing (1640)
DE: 1866 Soil moisture
DE: 1895 Instruments and techniques: monitoring
SC: Hydrology [H]
MN: 2007 Fall Meeting