SCIENTIA GEOGRAPHICA SINICA ›› 2017, Vol. 37 ›› Issue (2): 283-291.doi: 10.13249/j.cnki.sgs.2017.02.015

• Orginal Article • Previous Articles     Next Articles

Spatiotemporal Characteristics of Extreme Precipitation Regimes and Related Driving Factors in the Pearl River Basin

Jiangyu Zheng1(), Qiang Zhang2,3,4(), Peijun Shi2,3,4, Xihu Gu1, Yongjie Zheng1   

  1. 1.Department of Water Resources and Environment, Sun Yat-sen University, Guangzhou 510275, Guangdong, China
    2.Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education, Beijing Normal University, Beijing 100875, China
    3.Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
    4.Academy of Disaster Reduction and Emergency Management, Beijing Normal University, Beijing 100875, China
  • Received:2016-03-03 Revised:2016-06-11 Online:2017-02-25 Published:2017-02-25
  • Supported by:
    Fund for Creative Research Groups of National Natural Science Foundation of China (41621061);National Science Foundation for Distinguished Young Scholars of China (51425903)

Abstract:

Daily precipitation and temperature data of 74 weather stations of the Pearl River Basin in 1952-2013 were analyzed to characterize spatiotemporal characteristics of extreme precipitation in terms magnitude, frequency and occurrence time by using the peaks-over-threshold approach (POT), Mann-Kendall test(MK) and Poisson Regression Model for the whole year, wet season(April-September) and dry season(October-March). In addition, causes behind extreme precipitation changes were investigated by relating spatiotemporal patterns of extreme precipitation to ENSO and large-scale moisture circulation. The results indicate that:1) Extreme precipitation over the Pearl River Basin is in uneven. Precipitation extreme mainly occurs from April to September and highest extreme precipitation regimes can be found in June; 2) The frequency of extreme precipitation across the Pearl River Basin during wet season and whole year is even. However, occurrence rates of extreme precipitation within the Pearl River Delta during dry season tends to be uneven with significant difference in annual frequency of extreme precipitation;3) Magnification of extreme precipitation can be observed during dry season with respect to precipitation magnitude and occurrence rates. Besides, occurrence timing of extreme precipitation regimes tends to be earlier. However, no significant trend can be identified in extreme precipitation during wet season and during the entire year. Winter flood has the potential to causeagriculturalloss. Therefore, wetting tendency of dry season can pose new challenges for regional water resources management; 4) Warming climate across the Pearl River Basin and variations of warm and cold episodes of ENSO have significant effects on extreme precipitation processes. From the perspective of the ENSO’s influence, magnitude and frequency of extreme precipitation over the west of the Pearl River Basin increases in El Ni?o years with decreased magnitude of extreme precipitation in the lower Pearl River Basin.

Key words: extreme precipitation, clustering, poisson process, ENSO, the Pearl River Basin

CLC Number: 

  • P333.2