贵州省1960~2017年降水时空变化特征

Spatial-temporal variation characteristics of precipitation pattern in Guizhou Province from 1961 to 2017

针对近年来区域降水异常事件频发的问题,选取了贵州省32个气象站近57 a(1960~2017年)来的逐日降水数据,利用降水发生率和贡献率,分析该地区不同历时和等级降水条件下的时空变化规律,并运用Mann-Kendall法探讨了不同历时降水和不同降水等级的变化趋势。结果表明:①降水发生率随着降水历时增加呈逐渐减少的趋势;而贡献率则呈先增加后减少的趋势。桐梓、正安、仁怀、余庆、思南、铜仁、贵阳、罗甸和榕江2~4 d的降水贡献率较大;威宁、普安、盘县、织金、兴仁和兴义大于10 d的降水贡献率较大。②降水发生率随着降水等级的增加呈减少趋势,而贡献率则呈先增加后减少趋势。其中望谟、织金、都匀和安顺暴雨贡献率较高。③各历时降水贡献率和发生率变化趋势基本类似,表现为短历时呈增加趋势的站点较多,多数历时发生率呈增加趋势的站点较多。各等级的降水贡献率和发生率的变化趋势也基本类似,大雨和暴雨呈增加趋势,小雨呈减少趋势,中雨发生率呈增加趋势,贡献率则反之。研究成果可为贵州地区防灾减灾工作提供一定科学依据。

In view of the frequent occurrence of regional precipitation anomalies in recent years,we analyzed the spatial-temporal variation characteristics of precipitation pattern in Guizhou Province based on the daily precipitation data from 32 meteorological stations in 57 years(1960~2017)in Guizhou Province.In this paper,the incidence rate and contribution rate of precipitation events were used to assess the precipitation variations.The Mann-Kendall test was adopted to investigate the trends of precipitation change.The results showed that:①With the increase of precipitation duration,the incidence rate of precipitation events displayed a decreasing trend,and the contribution rate of precipitation events increased first then decreased.The contribution rates of 2~4 d duration precipitation events were high in Tongzi,Zhengan,Renhuai,Yuqing,Sinan,Tongren,Guiyang,Luodian and Rongjiang meteorological stations.The contribution rates of>10d duration precipitation events were high in Weining,Pu'an,Panxian,Zhijin,Xingren and Xingyi meteorological stations.②With the increase of precipitation grades,the incidence rate of precipitation events displayed a decreasing trend,and the contribution rate of precipitation events increased first then decreased.The contribution rates of precipitation events were high in Wangmo,Zhijin,Duyun and Anshun meteorological stations.③In terms of precipitation duration,the varying trends were similar for incidence rate and contribution rate.The upward trend was detected in the short-duration precipitation events,while the downward trend was detected in other duration precipitation.In terms of precipitation grades,the changing trends were similar for the incidence rate and the contribution rate.Heavy and storm rain events showed an increasing trend,and a decreasing trend was found in light rain events.However,an increasing trend was found in the incidence rate of moderate rain events,the opposite trend was found in the contribution rate of moderate rain events.The results could provide a scientific basis for the disaster prevention and mitigation in Guizhou Province.