Arid Zone Research ›› 2021, Vol. 38 ›› Issue (5): 1295-1305.doi: 10.13866/j.azr.2021.05.11

• Applied Climate • Previous Articles     Next Articles

Spatiotemporal characteristics of extreme precipitation in Shaanxi Province based on the regional L-moments method

LUO Zhiwen1,2(),WANG Xiaojun3,4(),LIU Mengyang2,KE Hang5,WAN Ting6,YIN Yixing2   

  1. 1. Power China Jiangxi Electric Power Engineering Co., LTD., Nanchang 330096, Jiangxi, China
    2. Nanjing University of Information Science and Technology, Nanjing 210044, Jiangsu, China
    3. Nanjing Hydraulic Research Institute, State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Nanjing 210029, Jiangsu, China
    4. Research Center for Climate Change, Ministry of Water Resources, Nanjing 210029, Jiangsu, China
    5. Fuzhou Meteorology Bureau, Fuzhou 350008, Fujian, China
    6. Jiangxi Science and Technology Exchange Center, Nanchang 330096, Jiangxi, China
  • Received:2021-03-04 Revised:2021-06-24 Online:2021-09-15 Published:2021-09-24
  • Contact: Xiaojun WANG E-mail:luozhiwen567@163.com;xjwang@nhri.cn

Abstract:

Extreme precipitation can cause severe disasters in arid and semi-arid regions, such as in the Shaanxi Province of Northern China. To investigate the spatiotemporal characteristics of extreme precipitation in the Shaanxi Province, this study adopted the daily precipitation data of 58 meteorological stations from 1971 to 2015 with no missing observations and relatively uniform distribution and used the maximum precipitation on the 1st, 3rd, 5th, and 7th day to represent the extreme precipitation. The regional L-moments method was further applied to study the temporal and spatial characteristics of the extreme regional precipitation, which involves the screening and processing of precipitation data, identification of homogeneous regions, goodness-of-fit test, quantile estimation for each region, comparison between at-site and regional estimation, deriving regional growth factors, and mapping of the spatial patterns of extreme precipitation. The results and conclusions of the study were: (1) Shaanxi Province can be divided into six hydrometeorological homogeneous regions, among which GEV distribution in each homogeneous region has the best simulation effect, and the estimated optimal quantiles of each homogeneous region are in good agreement with the measured value of the same frequency. (2) The estimated extreme precipitation quantiles calculated by the regional analysis method have better robustness and accuracy compared with the single-station analysis method, especially more significant in calculating extreme precipitation over a long period. (3) When the return period is once every 2 years, the regional growth factor of southern Shaanxi is greater than that of northern Shaanxi; when the return period is once every 5 years, the opposite is true, and with the increase of the return period, the regional growth factor and the difference between southern Shaanxi and northern Shaanxi also increase. (4) In the 100-and 50-year return periods, extreme precipitation is large in the south, centered in the east, the Xianyang-Shangluo region in the middle, the northwest corner of Yan’an in the west, and the west of Yulin are small. The distribution characteristics of extreme precipitation are related to the unique geographical characteristics of Shaanxi Province, especially the east-west Qinling Mountains, which block the water vapor transmission to the north, causing differences in extreme precipitation between the north and south.

Key words: Shaanxi Province, extreme precipitation, spatiotemporal characteristics, regional L-moment method