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（M-K）方法进行趋势分析，滑动 t 检验（MTT）、Mann-Kendall、Qettit 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、QRCQTOT）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、QRCQTOT 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。
Spatio-temporal Characteristics of Extreme Precipitation in Yunnan Province from 1958 -2013
Changes of extreme precipitation in Yunnan Qrovince,southwestern China,are analyzed by using observed daily data from 28 meteorological stations during the period of 1 958 -201 3.In order to detect possible trends,change points,periods and spatial distributions of the time series,analysis were performed with Mann-Ken-dal trend test,moving t test,Mann-Kendall abrupt change analysis,Qettit test and inverse distance weighting.Re-sults indicated that annual total wet-day precipitation (QRCQTOT)displayed a downward tendency at the rate of -1 1 .8mm /1 0a,consecutive wet days (CWD),number of heavy precipitation days (R1 0 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),R1 0,R20 and QRCQTOT,CWD,which can reflect the characteristics of average precipitation,were not detected.Change points in CWD,very wet days (R95p),ex-treme wet days (R99p),and simple daily intensity index (SDII)were detected in 2002,1 993,1 980 and 1 994, respectively.These indices reflect the changes of extreme precipitation features sensitively and efficiently.All ex-treme precipitation indices had similar oscillation cycles except the CDD,R99p and SDII,which had three main characteristic timescales at 28a,22a and 1 3a,and the corresponding cycle is 1 8 year,1 4 year,and 8 years,re-spectively.According the meteorological geographic zoning,the precipitation ranks from high to low in Yunnan Qrovince was southwest,southeast,northwest,central,and northeast.Except CDD,CWD,SDII,and QRCQTOT, spatiotemporal distribution for other indices were consistent with each other.The maximum precipitation did not oc-cur 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 compara-tively 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 Qrovince.
国家科技期刊平台
NSTL
万方数据
维普
