1961年-2016年鲁中地区极端降水时空变化特征及与ENSO关系研究

Spatial-temporal Variation Characteristics of Extreme Precipitation and Its Relationship with ENSO in Central Shandong from 1961 to 2016

利用RClimdex软件计算1961年-2016年鲁中地区18个站点极端降水指数,结果表明:在研究时段内,降水强度有上升趋势,极端降水指数均呈现非显著性下降趋势;鲁中东部、西南部降水强度呈现减少趋势,其他区域则均呈现增加趋势;鲁中北部的强降雨日数、日最大与连续5日最大降水量超过95%、99%阈值的次数均呈增加趋势,而鲁中西部则呈现减少趋势;日最大降水量与连续5日最大降水量一般在夏秋两季,且在冬、春两季均呈现上升趋势;ENSO强度与同年的降水指数是反相关,与次年的连续降雨日数成正相关。

RClimdex was used to calculate the extreme precipitation index of 18 stations in central Shandong from 1961 to 2016.The results showed that:the precipitation intensity showed an upward trendduring the study period,while the extreme precipitation indexes showed a non-significant downward trend.The precipitation intensity showed a decreasing trend in the central and eastern part and southwest part of Shandong province,while it showed an increasing trend in other regions.The number of heavy rainfall days,daily maximum and consecutive 5-day maximum precipitation in the central and northern part of Shandong increased,while the number of precipitation over 95%and 99%thresholds decreased in the central and western part of Shandong.Daily maximum precipitation and consecutive 5-day maximum precipitation generally occurred in summer and autumn,and showed an upward trend in winter and spring.ENSO intensity was inversely correlated with the precipitation index of the same year and positively correlated with the number of consecutive rainfall days in the next year.