Submitted to: American Geophysical Union
Publication Type: Abstract Only
Publication Acceptance Date: 3/15/2004
Publication Date: 5/17/2004
Citation: Jackon, T.J., Lettenmair, D. 2004. Soil Moisture Experiments 2004 (SMEX 04)[abstract]. EOS, Transactions, American Geophysical Union. 85(17):JA181. Interpretive Summary:
Technical Abstract: Soil Moisture Experiments 2004 (SMEX04) will be conducted during the summer of 2004 to address overlapping science issues of the North American Monsoon Experiment (NAME) and soil moisture remote sensing programs. Surface boundary conditions play an important role in initiation and maintenance of the system that controls summer precipitation over much of the NAME region. A working hypothesis of NAME is that among the land surface antecedent boundary conditions that control the onset and intensity of the precipitation is soil moisture in the southwestern U.S. and northern Mexico. Surface soil moisture can change dramatically after rain events. This increased soil moisture after precipitation can increase evapotranspiration between storm events, which may contribute to enhanced convection and further precipitation. Soil moisture can vary both spatially, due to topography, soil, vegetation and precipitation variability, and temporally, due to differences in soil physical characteristics that control drainage and accumulated evapotranspiration. SMEX04 will focus on providing these critical soil moisture products using the new generation of satellite sensors supported by insitu observations and high-resolution aircraft mapping. Intensive study regions will be established over 50 by 75 km domains in southeastern Arizona and northwestern Mexico. Insitu observations will be collected over an extended time frame. Aircraft mapping and intensive regional ground sampling will be performed between mid-July and Mid-August. The field campaign will at the same time contribute to the validation of these satellite products, expand our knowledge of the effects of key land surface features, establish algorithms for future satellite sensors, and explore the potential of new technologies.