2008 Joint Meeting of The Geological Society of America, Soil Science Society of America, American Society of Agronomy, Crop Science Society of America, Gulf Coast Association of Geological Societies with the Gulf Coast Section of SEPM

Paper No. 6
Presentation Time: 9:40 AM

Surface Energy Flux Estimation Using Diurnal Surface Temperature Modeling at BEAREX08

FRENCH, Andrew1, HUNSAKER, Doug2, COLAIZZI, Paul D.3, EVETT, Steven R.3, GOWDA, Prasanna H.3, HOWELL, Terry A.3, KUSTAS, William P.4, NEALE, Christopher M.U.5 and PRUEGER, J.H.6, (1)U.S. Water Conservation Lab, USDA-ARS, 21881 N. Cardon Lane, Maricopa, AZ 85239, (2)U.S. Arid Land Agricultural Research Center, USDA-ARS, 21881 N. Cardon Lane, Maricopa, AZ 85238, (3)Conservation and Production Research Laboratory, USDA-ARS, P.O. Drawer 10, Bushland, TX 79012-0010, (4)USDA-ARS Hydrology & Remote Sensing Laboratory, Bldg. 007 Rm. 104, Beltsville, MD 20705, (5)Biological and Irrigation Engineering Department, Utah State University, 4105 Old Main Hill, Logan, UT 84321, (6)ARS-USDA National Soil Tilth Laboratory, Ames, IA 50010, andrew.french@ars.usda.gov

Obtaining accurate estimates of the spatial distribution of surface energy fluxes through remote sensing techniques would be helpful for modeling daily evapotranspiration (ET) over crops such as cotton. Experience with energy balance models shows that techniques incorporating thermal infrared observations are particularly useful because departures from standardized ET estimates can be detected. Practical remote sensing from satellite platforms, however, precludes acquisitions at both high temporal and spatial resolutions. Consequently continuous estimation of surface fluxes over crops is not feasible without supplemental methods. One such method utilizes land surface temperature (LST) observations acquired from ground-based radiometers, which are then spatially extrapolated. The extrapolation process is constrained by vegetation densities and a sinusoidal/exponential diurnal LST model. Using data acquired from the BEAREX 2008, spatially and temporally continuous surface energy fluxes were estimated for cotton growing between June and August 2008. Results from these estimates, including comparisons against daily ET observations obtained from large, monolithic weighing lysimeters, will be discussed.