山西北部极端降水时空演变规律及与大气环流因子的响应OA北大核心CSTPCD
Temporal and spatial evolution of extreme precipitation and its response to atmospheric circulation factors in northern Shanxi Province
基于山西北部28个国家气象站点,1972-2020年逐日降水资料,选用8个极端降水指数,采用线性回归、Pearson相关分析、连续小波和交叉小波变换分析等方法,研究了山西北部极端降水的时空变化及其与大气环流因子的相关性和周期特征.结果表明:(1)在时间上,山西北部8个极端降水指数都是在20世纪70年代后期和21世纪00年代后期到10年代,年总降水量(PRCPTOT)、中雨以上日数(R10mm)、强降水量(R95P)、极强降水量(R99P)、1 d最大降水量(Rx1day)、5 d最大降水量(Rx5day)均增多,日降水强度(SDII)显著增强,持续湿期日数(CWD)也略有增多.整个20世纪80年代降水异常偏少.(2)在空间上,极端降水指数呈从东北向西南地区逐步增加的态势.从站点趋势变化来分析,大多数站点的极端降水指数呈上升趋势,其中,上升趋势最显著的站点均位于忻州市境内西南部.朔州市境内和忻州市东南部站点PRCPTOT和SDII都呈增加趋势,但CWD则呈减少趋势,由此说明朔州市境内和忻州市东南部地区发生极端降水事件的概率较大.(3)通过小波变换分析发现,1990-2020年山西北部极端降水指数表现出约4a左右的周期特征.在选取的大气环流指数中,北大西洋涛动指数(NAO)对山西北部极端降水影响最明显,NAO越大,PRCPTOT、R10mm、R95p、R99p、Rx1day、Rx5day、SDII则越小,同时CWD也越少,山西北部产生少雨干旱的几率较大,反之,易发生多雨、洪涝现象.研究结果可为山西北部气象灾害的防御提供科学理论依据.
Based on daily precipitation data from 28 national meteorological stations in northern Shanxi Prov-ince,China,from 1972 to 2020,temporal and spatial changes in extreme precipitation in northern Shanxi and their correlation with atmospheric circulation factors and periodic characteristics were studied using linear regres-sion,Pearson correlation analysis,continuous wavelet analysis,and cross wavelet transform analysis.The results show the following:(1)In terms of time,the eight extreme precipitation indices in northern Shanxi increased sig-nificantly in the late 1970s and from the late 2010s to the early 2000s:annual total wet-day precipitation(PRCP-TOT),number of heavy precipitation days(R10mm),soaked days(R95P),extremely wet days(R99P),maximum 1-day precipitation amount(Rx1day),and maximum 5-day precipitation amount(Rx5day).The simple daily in-tensity index(SDII)increased significantly,and consecutive wet days(CWD)also increased slightly.Precipita-tion was unusually low throughout the 1980s.(2)Spatially,the extreme precipitation indices gradually increased from northeast to southwest.From the analysis of the stations'trend change,the extreme precipitation indices of most stations showed an upward trend,with the most significant upward trend of the stations located southwest of Xinzhou City.PRCPTOT and SDII in Shuozhou City and southeast of Xinzhou City showed an increasing trend.However,days of CWD showed a decreasing trend,indicating that the probability of extreme precipitation events in Shuozhou City and the southeast of Xinzhou City was high.(3)Through wavelet transform analysis,it was dis-covered that the extreme precipitation indices in northern Shanxi had a periodic feature of recurring in approxi-mately 4 years in the past 30 years.Among the selected atmospheric circulation indices,the North Atlantic Oscil-lation Index(NAO)had the most obvious influence on extreme precipitation in northern Shanxi.The larger the NAO,the smaller the PRCPTOT,R10mm,R95p,R99p,Rx1day,Rx5day,and SDII,and the lower the CWD,the greater the probability of low rainfall and drought in northern Shanxi,which is prone to flash flooding.The re-search results can provide a scientific theoretical basis for the prevention of meteorological disasters in northern Shanxi.
蔡霞;梁桂花;张冬峰;蔡琳;白樱;李锐锋
山西省朔州市气象局,山西 朔州 036002山西省朔州市朔城区气象局,山西 朔州 036002山西省气候中心,山西 太原 030006山东省菏泽学院,山东 菏泽 274000河北省邯郸市气象局,河北 邯郸 056001山西省朔州市平鲁区气象局,山西 朔州 036002
极端降水指数时空分布大气环流异常因子小波分析山西北部
extreme precipitation indicesspatiotemporal distributionatmospheric circulation anomaly factorwavelet analysisnorthern Shanxi
《干旱区地理》 2024 (003)
391-402 / 12
山西省气象局课题(SXKMSQH20236329);山西省重点研发计划项目(201803D31219);菏泽学院科研基金计划项目(扶贫专项)(XY18FP08)资助
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