Journal of Geographical Sciences ›› 2010, Vol. 20 ›› Issue (4): 557-568.doi: 10.1007/s11442-010-0557-3

• Climate Change • Previous Articles     Next Articles

Trend in pan evaporation and its attribution over the past 50 years in China

LIU Min1,2, SHEN Yanjun1, ZENG Yan3, LIU Changming4   

  1. 1. Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, CAS, Shijiazhuang 050021, China;
    2. Graduate University of Chinese Academy of Sciences, Beijing 100049, China;
    3. Jiangsu Institute of Meteorological Sciences, Nanjing 210008, China;
    4. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China
  • Received:2009-05-18 Revised:2009-08-10 Online:2010-08-15 Published:2010-08-15
  • Contact: Shen Yanjun, Ph.D and Professor, E-mail: yjshen@sjziam.ac.cn E-mail:yjshen@sjziam.ac.cn
  • About author:Liu Min (1982–), Ph.D Candidate, specialized in hydrology and water resources in response to climate change. E-mail: agnes0505@163.com
  • Supported by:

    Innovation Knowledge Project of the Chinese Academy of Sciences, No.KZCX2-YW-448; National Key Technology R&D Program, No.2007BAC03A06-01

Abstract:

Trends in pan evaporation are widely relevant to the hydrological community as indicators of hydrological and climate change. Pan evaporation has been decreasing in the past few decades over many large areas with differing climates globally. This study analyzes pan evaporation data from 671 stations in China over the past 50 years in order to reveal the trends of it and the corresponding trend attribution. Mann-Kendall test shows a significant declining trend in pan evaporation for most stations, with an average decrease of 17.2 mm/10a in China as a whole, the rate of decline was the steepest in the humid region (29.7 mm/10a), and was 17.6 mm/10a and 5.5 mm/10a in the semi-humid/semi-arid region and arid region, respectively. Complete correlation coefficients of pan evaporation with 7 climate factors were computed, and decreases in diurnal temperature range (DTR), SD (sunshine duration) and wind speed were found to be the main attributing factors in the pan evaporation declines. Decrease in DTR and SD may relate to the increase of clouds and aerosol as well as the other pollutants, and decrease in wind speed to weakening of the Asian winter and summer monsoons under global climate warming.

Key words: pan evaporation, Mann-Kendall test, diurnal temperature range, wind speed, compete correlation, China