Satellite-Derived Spatiotemporal Variations in Evapotranspiration over Northeast China during 1982–2010

Remote Sensing

Yuhu Zhang¹  Zhiqiang Wang²  Jia Xu³  Lilin Zhang³  Xiaotong Zhang³  Kun Jia³  Yunjun Yao³  Xuanyu Wang³  Xiaowei Chen³ 

[1] College of Resource Environment and Tourism, Capital Normal University, Beijing 100048, China;National Disaster Reduction Center/Satellite Application Center for Disaster Reduction of the Ministry of Civil Affairs, Beijing 100124, China;State Key Laboratory of Remote Sensing Science, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China;

关键词: evapotranspiration;    Northeast China;    MS–PT algorithm;    spatial-temporal variations;    controlling factors;    potential evapotranspiration;   

DOI  :  10.3390/rs9111140

来源: DOAJ

【 摘 要 】

Evapotranspiration (ET) is a critical process for the climate system and water cycles. However, the spatiotemporal variations in terrestrial ET over Northeast China over the past three decades calculated from sparse meteorological point-based data remain large uncertain. In this paper, a recently proposed modified satellite-based Priestley–Taylor (MS–PT) algorithm was applied to estimate ET of Northeast China during 1982–2010. Validation results show that the square of the correlation coefficients (R2) for the six flux tower sites varies from 0.55 to 0.88 (p < 0.01), and the mean root mean square error (RMSE) is 0.92 mm/d. The ET estimated by MS–PT has an annual mean of 441.14 ± 18 mm/year in Northeast China, with a decreasing trend from southeast coast to northwest inland. The ET also shows in both annual and seasonal linear trends over Northeast China during 1982–2010, although this trend seems to have ceased after 1998, which increased on average by 12.3 mm per decade pre-1998 (p < 0.1) and decreased with large interannual fluctuations post-1998. Importantly, our analysis on ET trends highlights a large difference from previous studies that the change of potential evapotranspiration (PET) plays a key role for the change of ET over Northeast China. Only in the western part of Northeast China does precipitation appear to be a major controlling influence on ET.

【 授权许可】

Unknown