Testing of Two Source Energy Balance Model Under Irrigated and Dryland Conditions Using High Resolution Airborne Imagery.

Two Source Energy Balance Model (TSM), also referred as dual source model, separately calculates the heat and water exchange and interaction between soil-atmosphere and vegetation-atmosphere. This is achieved through decomposition of radiometric surface temperature to soil and vegetation component temperatures either from multi-angular remotely sensed thermal data or from an iteration of respective solution of soil and vegetation energy balance. This study combines high resolution remote sensing data with  field measurements of the agro-meteorological variables and surface energy fluxes to evaluate TSM parameterizations. High resolution aircraft images (0.5-1.8 m) acquired during the Bushland Evapotranspiration and Agricultural Remote Sensing Experiment 2007 and 2008 ( BEAREX07, BEAREX08 ) conducted at the USDA-ARS Conservation and Production Research Laboratory (CPRL) in Bushland, Texas, were used. The CPRL has four large weighing lysimeters (3 m long x 3 m wide x 2.4 m deep) each located in the middle of a 4.3 ha fields arranged in a block pattern. Two lysimeters fields located on the east (NE and SE) are managed under irrigation conditions and two lysimeters on the west (NW and SW) are managed under dryland conditions. Each lysimeter field was equipped with net radiometer, infra-red thermometer and soil heat flux plates for measuring net radiation, radiometric surface temperature, and soil heat fluxes, respectively. Apart from the above instrumentation, each lysimeter field had an automated weather station. In addition a grass reference ET weather station field (0.31 ha), which is a part of the Texas High Plains ET Network is located on the eastern edge of the irrigated lysimeter fields