海南岛极端降水时空变化特征分析

Analysis on Spatio-temporal Change Characteristics of Extreme Precipitation in Hainan Island

基于海南岛188个雨量站1980—2022年9个极端降水指数,采用线性回归、滑动平均、累积距平法、Mann-Kendall检验、滑动T检验、Lee-Heghinian检验、R/S分析法等方法,分析海南岛极端降水时空变化特征及未来变化趋势,并进行突变检验。结果表明:①海南岛极端降水事件空间分布呈“东多西少”,东部降水多且更易发生暴雨,西部尖峰岭也有较大可能出现短时强降雨;②43 a来全岛趋向湿润化,1、3 d的短时降水量呈北部、西部增加,南部减少,CWD增加,CDD减少,东部、北部和西部沿海部分地区发生暴雨、大暴雨趋势加大;③极端降水量指数PRCPTOT、Rx1day、Rx3day、R99PTOT分别以45.57、1.62、6.08、2.80 mm/10a速率不显著增加,极端降水日数指数CDD以2.07 d/10a的速率显著减少,CWD、R50、R100分别以0.26、0.22、0.02 d/10a不显著增加,极端降水强度指数SDII以0.18(mm/d)/10a不显著减少;④CDD、SDII未来将会以持续性较强的趋势增加,PRCPTOT、Rx1day、Rx3day、R99PTOT、CWD、R50、R100将会以持续性较弱的趋势减少;⑤突变检验显示PRCPTOT、Rx1day、Rx3day、R99PTOT、R50和R100突变点发生在2007年前后,SDII突变点出现在1988年,CWD、CDD突变点出现在1995、2010年左右。研究结果可为海南岛暴雨灾害防御提供参考。

The spatio-temporal variation characteristics and future trends of extreme precipitation in Hainan Island are analyzed based on 9 extreme precipitation indices from 188 rainfall stations in Hainan Island from 1980 to 2022,by means of methods such as linear regression,moving average,cumulative anomaly method,Mann-Kendall test,sliding T-test,Lee-Heghinian test,R/S analysis method.Then mutation analysis on the extreme precipitation index sequence is performed.The results show that:①The spatial distribution of extreme precipitation events in Hainan Island is"more in the east and less in the west";the eastern part has more precipitation and is more prone to rainstorms,and Jianfengling in the western part is also more likely to have short-term heavy rainfall.②In the past 43 years,the entire island has been tending towards humidification,with short-term precipitation on the 1st and 3rd day increasing in the north and west,and decreasing in the south;consecutive wet days(CWD)increase,consecutive dry days(CDD)decreases,and the trend of rainstorms and heavy rainstorms increases in eastern,northern and western coastal areas.③Extreme precipitation indices PRCPTOT,Rx1day,Rx3day,and R99PTOT show an insignificant increase at rates of 45.57,1.62,6.08,and 2.80 mm/10a,respectively;among the extreme precipitation day indices,CDD significantly decreases at a rate of 2.07 d/10a,while CWD,R50,and R100 show an insignificant increase at 0.26,0.22,and 0.02 d/10a,respectively;the extreme precipitation intensity index SDII show an insignificant decrease at 0.18(mm/d)/10a.④In the future,CDD and SDII will continue to increase with strong persistence,and PRCPTOT,Rx1day,Rx3day,R99PTOT,CWD,R50,and R100 will continue to decrease with weak persistence.⑤Mutation test shows that mutations in PRCPTOT,Rx1day,Rx3day,R99PTOT,R50,and R100 occurred around 2007,the SDII mutation point appeared in 1988,and the CWD and CDD mutation points appeared around 1995 and 2010,respectively.These results can provide a reference for rainstorm disaster prevention in Hainan Island.