Submitted to: Remote Sensing for Agriculture Ecosystems and Hydrology
Publication Type: Abstract Only
Publication Acceptance Date: June 18, 2002
Publication Date: September 23, 2002
Citation: Schmugge, T.J., French, A.N., Jacob, F., Ritchie, J.C., Chopping, M.J., Rango, A. 2002. ASTER thermal infrared observations over New Mexico [abstract]. Remote Sensing for Agriculture Ecosystems and Hydrology.
More than ten clear sky ASTER scenes over the Jornada, New Mexico LTER site have been acquired since the launch of NASA's Terra satellite in December, 1999. The Advanced Spaceborne Thermal Emission Reflectance Radiometer (ASTER) instrument has 5 channels in the 8 to 12 micrometer wave band with 90 meter resolution. To support the ASTER overpasses there were simultaneous field campaigns for the 5/09/00, 5/12/01 and 9/17/01 scenes. Also, data from an airborne simulator, MASTER, were obtained for the 5/12/01 scene to provide high resolution (3 m) data roughly coincident with ASTER. The Jornada Experimental Range is a long term ecological reserve (LTER) and is at the northern end of the Chihuahuan desert. The site is typical of a desert grassland where the main vegetation components are grass and shrubs. The White Sands National Monument is also within several of the scenes. The Temperature Emissivity Separation (TES) algorithm was used to extract emissivity values from the ASTER data for the gypsum sand at White Sands. The results are in good agreement with values calculated from the lab spectra for gypsum and with each other. The results for sites in the Jornada show reasonable agreement with the lab results when the mixed pixel problem is taken into account. These results indicate ASTER and TES are working very well. The surface brightness temperatures from ASTER were in reasonable agreement with measurements made on the ground during the field campaigns. Bowen ratio flux measurements were made at two sites during several of the ASTER overpasses and the results have been compared with flux made with two different models again showing reasonable agreement.