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.
The data set SMEX04 Surface Roughness Data is comprised of data collected over the regional study areas of Arizona, USA and Sonora, Mexico as part of the 2004 Soil Moisture Experiment (SMEX04). The experiment was conducted 30 July 2004 to 25 August 2004 at various hydrologic network sites in Arizona and Sonora. Surface roughness parameters include root mean square error, correlation length, root mean square error adjusted for slope, and power coefficient. For each study area, surface roughness conditions were photographed using a grid board and the roughness photographs were then digitized using a SigmaScan pro 4 scanner in order to derive surface roughness calculations. The total volume for this combined data set is approximately 36 kilobytes. Data are provided in ASCII text files and are available via FTP.
These data were collected as part of a validation study for the Advanced Microwave Scanning Radiometer - Earth Observing System (AMSR-E). AMSR-E is a mission instrument launched aboard NASA's Aqua Satellite on 04 May 2002. AMSR-E validation studies linked to SMEX are designed to evaluate the accuracy of AMSR-E soil moisture data. Specific validation objectives include assessing and refining soil moisture algorithm performance; verifying soil moisture estimation accuracy; investigating the effects of vegetation, surface temperature, topography, and soil texture on soil moisture accuracy; and determining the regions that are useful for AMSR-E soil moisture measurements.