Study on daily surface evapotranspiration with SEBS in Tibet Autonomous Region

作     者：ZHUO Ga LA Ba PUBU Ciren LUO Bu ZHUO Ga;LA Ba;PUBU Ciren;LUO Bu;Tibet Institute of Plateau Atmospheric and Environmental Science

作者机构：Tibet Institute of Plateau Atmospheric and Environmental Science Lhasa 850000 China 

出 版 物：《Journal of Geographical Sciences》 (地理学报（英文版）)

年 卷 期：2014年第24卷第1期

页      面：113-128页

核心收录：

学科分类：07[理学] 08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0713[理学-生态学] 

基　　金：National Natural Science Foundation of China, No.41130960 No.41165011 Public Project of Meteorology, No.GYHy201006054 Major projects in Gansu Province, No. 1001JKA001 Project of the China Meteoro- logical Administration, No.CMAGJ2013M51 

主　　题：TAR SEBS P-M method ET PET estimation approach 

摘      要：The estimation of surface evapotranspiration （ET） with satellite dataset is one of the main subjects in the understanding of climate change, disaster monitoring and the circulation of water vapor and energy in Tibet Autonomous Region （TAR）. This research selects satellite images on January 11, April 6, July 31 and October 19 in 2010 as the representative of winter, spring, summer and autumn respectively, estimates the distribution of daily surface ET based on the surface energy balance system （SEBS） along with potential evapotranspiration （PET） and ET derived from Penman-Monteith （P-M） method. The results are obtained as follows. （1） The seasonal distribution of ET and PET basically decreases from the southeast part to the northwest part of TAR. Although ET and PET have similar spatial distributions, there are still some differences to estimate the extreme values especially the maximum value in the middle and southeastern parts of TAR. No matter what kind of methods we adopted, the maximum value of ET and PET always appears in summer, followed by autumn or spring while that in winter is the smallest. （2） In order to better understand the accuracy of SEBS model in the estimation of ET, we compared the ET from SEBS and the ET obtained from P-M method. Results show that the ET from SEBS could estimates the variation trend of actual ET, but it slightly underestimates or overestimates the value of ET as a whole, especially for those areas with thick forest. （3） The spatial distribution of Normalized Difference Vegetation Index （NDVI） exhibits a decreasing trend from the southeast part to the northwest part of TAR which displays remarkable consistency of distributions between ET and vegetation index. ET is well positively related to NDVI, minimum, mean, maximum air temperature and sunshine duration in different seasons while negatively related to precipitation, relative humidity and wind speed in summer.