Notice to Data Users: The documentation for this data set was provided solely by the Principal Investigator(s) and was not further developed, thoroughly reviewed, or edited by NSIDC. Thus, support for this data set may be limited.This data set consists of Vegetation Water Content (VWC) data for two Soil Moisture Experiment 2004 (SMEX04) regional study areas: Arizona, USA and Sonora, Mexico. VWC was derived from the Normalized Difference Infrared Index (NDII) which was obtained from Landsat 5 Thematic Mapper (TM) imagery.