摘要
利用云南省1958-2013年28个气象站日降水数据,计算了9个极端降水指数。基于Mann-Kendall(MK)方法进行趋势分析,滑动t检验(MTT)、Mann-Kendall、Pettit三种方法进行突变检验,小波分析、反距离权重法则分别探讨极端降水指数周期特性及空间分布特征。结果表明:1时间上,中小雨及连续降水日数均减小,极端降水量则显著增加,1958-2013年全省年降水量以-11.8 mm/10a的速率减少;较能反映降水均值特征的指数(CDD、R10、R20、PRCPTOT)未发生突变,而能反映极端降水变化特征的指数(CWD、R95p、R99p、SDII)的突变分别发生于2002、1993、1980、1994年左右;周期变化上,除CDD、R99p、SDII(周期分别为18年、14年、8年)外,其余指数的周期大小及其变化过程均较为相似,对应周期均为8年左右。2空间上,除CDD、CWD、SDII、PRCPTOT外,其余指数总体时空变化趋势较为一致。对比云南省5个气象地理分区降水,滇中降水量处于中等偏下水平,但该地区遭受极端干旱、极端降水风险高于其他地区,而其他地区极端降水与年平均降水量的空间分布特征较为一致。
Changes of extreme precipitation in Yunnan Province,southwestern China,are analyzed by using observed daily data from 28 meteorological stations during the period of 1958- 2013. In order to detect possible trends,change points,periods and spatial distributions of the time series,analysis were performed with Mann-Kendal trend test,moving t test,Mann-Kendall abrupt change analysis,Pettit test and inverse distance weighting. Results indicated that annual total wet-day precipitation（ PRCPTOT） displayed a downward tendency at the rate of-11. 8mm /10 a,consecutive wet days（ CWD）,number of heavy precipitation days（ R10 and R20） also showed a decreasing trend,while the contribution of extreme precipitation to total precipitation exhibited a significant upward trend. Change points in consecutive dry days（ CDD）,R10,R20 and PRCPTOT,CWD,which can reflect the characteristics of average precipitation,were not detected. Change points in CWD,very wet days（ R95p）,extreme wet days（ R99p）,and simple daily intensity index（ SDII） were detected in 2002,1993,1980 and 1994,respectively. These indices reflect the changes of extreme precipitation features sensitively and efficiently. All extreme precipitation indices had similar oscillation cycles except the CDD,R99 p and SDII,which had three main characteristic timescales at 28 a,22a and 13 a,and the corresponding cycle is 18 year,14 year,and 8 years,respectively. According the meteorological geographic zoning,the precipitation ranks from high to low in Yunnan Province was southwest,southeast,northwest,central,and northeast. Except CDD,CWD,SDII,and PRCPTOT,spatiotemporal distribution for other indices were consistent with each other. The maximum precipitation did not occur in central region; however extreme droughts and extreme precipitation risk in this region were higher than other areas. At the same time,the spatial distribution characteristics of extreme precipitation in other areas are comparatively similar with average annual precipitation. Overall,the extreme precipitation occurred more frequently,and extreme precipitation occurred more intensively since 2002. Further studies for the future should focus on extreme precipitation in Yunnan Province.
出处
《灾害学》
CSCD
2015年第4期178-186,共9页
Journal of Catastrophology
基金
中国工程院重大咨询项目“我国旱涝事件集合应对战略研究”(2012-ZD-13)
关键词
极端降水指数
趋势
周期
突变
空间分布
云南
extreme precipitation indices
tendency
period
abruption
spatial distribution
Yunnan
作者简介
杨晓静（1988-），女，云南昆明人，博士研究生，主要从事水文学及水资源方面研究．E—mail：yxj@mail.bnu.edu.cn
通讯作者：徐宗学（1962-），男，山东淄博人，教授，博士生导师，主要从事水文学及水资源研究．E-ail：zxxu@bnu.edu.cn
