Resources Science ›› 2018, Vol. 40 ›› Issue (8): 1658-1671.doi: 10.18402/resci.2018.08.15

• Orginal Article • Previous Articles     Next Articles

Evapotranspiration simulation and its spatio-temporal variation characteristics in Fenqin Region

Xiang HAN1,2(), Yunhe YIN1(), Shaohong WU1,2, Haoyu DENG1,2   

  1. 1. Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
    2. University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2018-03-22 Revised:2018-05-30 Online:2018-08-25 Published:2018-08-10

Abstract:

Evapotranspiration (ET) is a critical component in the surface energy budget as well as the water cycle. ET is also a key bond that connects the soil-vegetation-atmosphere system. With the climate change, studying the spatio-temporal distribution of ET has great implications in the reasonable allocation of regional water resources. This paper simulated the monthly ET based on water balance method using Gravity Recovery and Climate Experiment (GRACE) data in Fenqin Region from 2003 to 2015, and then analyzed its spatio-temporal dynamics in different time scales. It was found that the ET simulated by water balance method considering the water storage changes were more stable in the time series (the coefficient of variation, the standard variation, and the extreme values respectively reduced 0.12, 5.50mm, 3.20%), and more accurately in reflecting the temporal variations of annual and seasonal ET in Fenqin Region, comparing to the results simulated by water balance method neglecting the water storage changes. Average annual ET was 530.19mm in Fenqin Region from 2003 to 2015. There was a spatial distribution of increasing from north to south. Moreover, ET fluctuated quite smoothly during the study period with a lowest value in 2010 (478.22mm) and a highest value in 2011 (614.57mm), and the coefficient of variation was 0.08. At seasonal scale, ET was highest in summer (263.36mm) which accounted for 49.67% of annual ET and lowest in winter (19.50mm). Besides, the degree of dispersion was relatively higher in winter and lower in summer. The temporal variation of ET in Fenqin Region from 2003 to 2015 was mainly affected by precipitation and temperature, and the fluctuation of annual ET was mainly related to precipitation.

Key words: evapotranspiration, GRACE, water balance, precipitation, temperature, spatio-temporal distribution, Fenqin Region