Utility of a Thermal-Based Two-Source Energy Balance Model for Estimating Surface Fluxes over a Wide Variety of Landscapes
William P Kustas, USDA ARS, Beltsville, MD, United States, Martha Anderson, USDA Agricultural Research Service, Hydrology and Remote Sensing Laboratory, Beltsville, United States, Carmelo Cammalleri, JRC - IES, Climate Risk Management Unit, Ispra, Italy, Joseph G Alfieri, USDA Agricultural Research Service, Hydrology and Remote Sensing Laboratory, Beltsville, MD, United States, Kathryn A Semmens, Nurture Nature Center, Easton, United States, John H Prueger, U. S. Department of Agriculture, Agricultural Research Service, National Laboratory for Agriculture and Environment, Ames, United States, Christopher Hain, NASA Marshall Space Flight Center, Huntsville, AL, United States, Feng Gao, USDA ARS, Pendleton, OR, United States, Cezar Kongoli, University of Maryland, College Park, Earth System Science Interdisciplinary Center, College Park, MD, United States, Ana Andreu, Instituto de Investigacion y Formacion Agraria y Pesquera (IFAPA), Córdoba, Spain, Kyunghwa Han, Soil & Fertilizer Management Division, National Academy of Agricultural Science, RDA, Jeonju City, Korea, Republic of (South) and Ting Xia, Tsinghua University, Beijing, China
Abstract:
Many landscapes are comprised of a variety of vegetation types with different canopy structure, rooting depth, physiological characteristics, soil/substrate conditions, etc. Even in agricultural regions, different management practices, including crop rotations, irrigation scheduling, planting density, seed varieties, tilling practices, and other factors result in complex patterns in vegetation growth stages, canopy cover, canopy architecture, cropping densities and understory soil/substrate properties. This variability at the canopy, field and landscape scale, makes it very challenging to reliably quantify spatially-distributed surface fluxes. This paper describes a robust but relatively simple thermal-based energy balance model that parameterizes the key soil/substrate and vegetation exchange processes affecting the radiative balance and turbulent energy transport with the overlying atmosphere. The thermal-based model, called the Two-Source Energy Balance (TSEB) model solves for the soil/substrate and canopy temperatures that achieves a balance in the radiation and turbulent heat flux exchange with the lower atmosphere for the soil/substrate and vegetation elements. The TSEB scheme permits interaction between soil/substrate and canopy elements which are both are coupled to the atmosphere via canopy-air temperature that is strongly correlated to the aerodynamic surface temperature. In doing so the TSEB modeling framework is applicable to a wide range in atmospheric and land cover conditions. An overview of applications of the TSEB modeling framework to a variety of landscapes will be presented that include both natural and agricultural ecosystems having a soil/substrate with standing water (flooded), snow covered and vegetated (canopy understory) requiring different levels of refinements to the TSEB formulations for these unique land cover conditions. In addition, examples using a modeling framework that allows the TSEB scheme to be applied at regional scales using geostationary and polar orbiting satellites with a data fusion technique will be presented.
