Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: October 31, 2006
Publication Date: October 31, 2006
Citation: Hunt, E.R., Yilmaz, M.T, Ustin, S.L., Vanderbilt, V.C. 2006. Vegetation water content data product validation using SMEX04 and SMEX05 data [abstract]. MODIS Science Team Meeting. 2006 CDROM.
The Soil Moisture Experiments in 2004 (SMEX04) and 2005 (SMEX05) had a subobjective on developing and testing algorithms for a vegetation water content (VWC) data product for the NASA sensor MODIS and the NOAA sensor VIIRS. We choose a simple remotely sensed index as a backup algorithm. The index is the normalized difference infrared index (NDII), which is linear with respect to foliar water content from 0 to 1 kg/m2. The standard error of the regression is 0.07 kg/m2, which is equivalent to about a leaf area index of 0.5 m2/m2. Based on modeling the dynamic water flow through plants, the requirement for detection of water stress is about 0.01 kg/m2, so detection of water stress may not be possible. However, this standard error is accurate for detection of forest-fire fuel dryness and for input into the tau-omega model for soil moisture.