Yang Yuting, Scott R, Shang Songhao. Modeling evapotranspiration and its partitioning over a semiarid shrub ecosystem from satellite imagery: a multiple validation. Journal of Applied Remote Sensing, 2013, 7(1): 071599(1-12), doi: 10.1117/1.JRS.7.073495

 Abstract.Numerous modeling approaches have been proposed to estimate evapotranspiration(ET) and its partitioning between evaporation from soil (E) and transpirationfrom vegetation (T) over the last several decades. Although these ET modelsclaimed to give reasonable E and T partitioning, few studies have comparedtheir modeling results with direct E and T observations. In this study, ahybrid dual source scheme and trapezoid framework based evapotranspirationmodel (HTEM) fed with MODIS data was applied in a Chihuahuan Desert shrublandduring the growing season of 2003 and validated with direct ET measurementusing the Bowen-ratio technique and T measurement using scaled-up sap-flowmeasurements. Results show that the HTEM is capable of decomposing the remotelysensed land surface temperature into temperature components (soil and canopytemperatures) and providing accurate E and T estimates. At satellite overpasstime, the root-mean-square error (RMSE) of estimated latent heat flux (LE) is47.7 W/m^2. The agreement between estimated and simulated LE was largelyimproved when observed net radiation and ground heat flux were used (35.1W/m^2). At daily scale, the RMSE of estimated daily ET, E, and T are 0.52,0.36, and 0.41 mm/day, respectively.

梯形状态空间示意图（Fc-LST）