关键词：
极端降水事件;Kendall-tau;气候分区;降水指数;河套地区
摘 要：
采用河套地区73个国家基本气象站1951—2014年气象数据,在模糊聚类法划分子区域的基础上,利用Kendall-tau非参数检验和Sen’s斜率估计相结合的方法,分析了该地区极端降水指标的变化趋势。结果表明:(1)在河套地区的干旱半干旱子区(黄河上游),湿润半湿润子区(黄河中下游),极端降水事件的变化趋势是不同的,降水空间分布不均衡。(2)河套地区的干旱半干旱子区的极端潮湿天的降水量R99p指标显著增加,变化速率为32.01 mm·(10a)-1。其他10个指标均呈非显著增加趋势,变化速率分别为:强降水日数R10mm:0.05d·(10a)-1,非常强降水日数R20mm:0.16 d·(10a)-1,极强降水日数R25mm:0.19 d·(10a)-1,年度总降水量PRCPTOT:18.28 mm·(10a)-1,非常潮湿天的降水量R95p:30.82 mm·(10a)-1,1日最大降水量Rx1day:0.19mm·(10a)-1,5日最大降水量Rx5day:1.04 mm·(10a)-1,普通日降水强度SDII:0.26 mm·d-1·(10a)-1,说明该子区域极端降水事件发生呈上升趋势。而该区域连续无雨日数CDD和连续有雨日CWD指标都呈增加趋势,分别为0.91 d(10a)-1和0.18 d(10a)-1,也说明干旱和强降水过程都会在这个区域发生,时而无雨、时而强雨,区域降水极端化趋势明显。(3)河套地区的湿润半湿润子区域除CDD和CWD指标呈上升趋势外[CDD:2.00d·(10a)-1,CWD:0.03 d·(10a)-1],其他9个指标都呈非显著下降趋势,R10mm:-0.12 d·(10a)-1,R20mm:-0.16 d·(10a)-1,R25mm:-0.11 d·(10a)-1,PRCPTOT:-12.24 mm·(10a)-1,R95p:-8.11 mm·(10a)-1,R99p:-5.94 mm·(10a)-1,Rx1day:-0.43 mm·(10a)-1,Rx5day:-0.43 mm·(10a)-1,SDII:-0.03mm·d-1·(10a)-1,说明该子区域降水、降水强度、强降水持续日数都在减少。但在这种减少的趋势下,降水仍存在极端化趋势。
译 名：
Climatic Characteristics of Extreme Precipitation Events in Hetao in Recent Half A Century
作 者：
FENG Ke-peng;TIAN Jun-cang;SHEN Hui;College of Civil and Hydraulic Engineering,Ningxia University;Ningxia Research Center of Technology on Water-saving Irrigation and Water Resources Regulation;Engineering Research Center for Efficient Utilization of Water Resources in Modern Agriculture in Arid Regions;
单 位：
College of Civil and Hydraulic Engineering,Ningxia University%Ningxia Research Center of Technology on Water-saving Irrigation and Water Resources Regulation%Engineering Research Center for Efficient Utilization of Water Resources in Modern Agriculture in Arid Regions
关键词：
extreme precipitation event;;Kendall-tau;;climate district;;precipitation Index;;Hetao area
摘 要：
Based on the meteorological data from 73 basic meteorological stations in the Hetao area during the period from 1951 to 2014 and the trend of indicators,the Kendall-tau nonparametric test method,Sen's slope estimation method and fuzzy clustering method were used to analyze the extreme precipitation in the study area. The results are as follows:(1) In the arid and semiarid regions located in the upper reaches of the Yellow River and the humid and subhumid regions located in the middle and lower reaches of the river in Hetao,the trend of extreme precipitation events was different,and the spatial distribution of precipitation was very uneven;(2) The annual precipitation,precipitation intensity and duration of heavy precipitation,especially the R99 p index in the arid and semiarid regions in Hetao increased significantly,and the PRCPTOT: 18. 28 mm ·(10 a)-1,R95 p: 30. 82 mm·(10 a)-1,R99 p:32. 01 mm·(10 a)-1,Rx1 day: 0. 19 mm·(10 a)-1,Rx5 day: 1. 04 mm·(10 a)-1 and SDII: 0. 26 mm·d-1·(10 a)-1 indicated that the occurrence of extreme precipitation events in these regions was on the rise. The increase of CDD index of continuous rainy days in the study area was 0. 91 d ·(10 a)-1,which also showed that both drought and heavy precipitation occurred,and extreme precipitation was very significant;(3) In the humid and subhumid regions in the Hetao area,the other 9 indicators showed a non-significant decreasing trend,and the R10 mm:-0. 12 d·(10 a)-1,R20 mm:-0. 16 d·(10 a)-1,R25 mm:-0. 11 d·(10 a)-1,PRCPTOT:-12. 24 mm·(10 a)-1,R95 p:-8. 11 mm·(10 a)-1,R99 p:-5. 94 mm·(10 a)-1,Rx1 day:-0. 43 mm·(10 a)-1,Rx5 day:-0. 43 mm·(10 a)-1,SDII:-0. 03 mm·d-1·(10 a)-1,except CDD and CWD indicators [CDD: 2. 00 d·(10 a)-1,CWD: 0. 03 d·(10 a)-1],were on the rise. These indicated that the precipitation,precipitation intensity and days of heavy precipitation decreased in these regions,and drought or flood occurred sometimes.
