【摘要】 极端降水是气候变化的重要研究内容之一。在全球气候变化背景下,探究秦岭地区的极端降水变化,对于明确区域极端气候差异及探究其机理具有重要的意义。基于秦岭地区1960—2015年29个气象站点降水数据以及秦岭25 m×25 m分辨率的DEM数据集,选取6个极端降水指数,运用最小二乘回归法、Man-Kendall突变检验法、5年滑动趋势法和克里金插值法研究了56年来秦岭地区极端降水的时空变化特征。结果表明:(1)秦岭地区极端降水分布存在明显空间差异性,西北部是年均连续无雨日数高值区,中西部为连续降水日数高值区;强降水日数、强降水量、5日最大降水量和降水强度等指数呈"南高北低"的分布格局,位于秦岭最南端的紫阳县是各个极端降水指数极大值区。(2) 56年来,秦岭地区极端降水的持续性整体呈减少趋势;强度呈增加趋势。秦岭山地降水时间短、强度大,尤其是在秦岭南部地区,应加强防备,以免引起洪水灾害造成的重大破坏。更多还原

【Abstract】 Extreme precipitation is one of the important research topics of climate change. Under the background of global climate change, study on the extreme precipitation variation in Qinling Mountains is of great significance for clarifying regional extreme climate difference and exploring its mechanism. Based on the precipitation data of 29 meteorological stations in Qinling Mountains from 1960 to 2015 and the DEM data set with the resolution of 25 m×25 m, six extreme precipitation indices were selected to study the spatial and temporal variation characteristics of extreme precipitation in Qinling Mountains in the past 56 years by using least square regression, Man-Kendall mutation test and 5-year sliding trend method and kriging interpolation method. The conclusions were as follows.(1) There were obvious spatial differences in the distribution of extreme precipitation in Qinling Mountains. The northwest part was the high value area of consecutive dry day(CDD), and the central and western parts were the high value areas of consecutive wet day(CWD). The distribution pattern of number of heavy precipitation days(R10), very wet days(R95 p), max 5-day precipitation amount(RX5 day) and simple daily intensity index(SDII) were high in the south and low in the north. Ziyang County, which is located at the southernmost end of Qinling Mountains, has the maximum value of all extreme precipitation indices.(2) In the past 56 years, the persistence of extreme precipitation in Qinling Mountains has decreased and the intensity has increased as a whole. Precipitation in Qinling Mountains was short and intense, especially in the southern aspect of Qinling Mountains. Relevant departments should strengthen their preparedness so as not to cause major damage caused by flood disasters.更多还原