1961～2017年中国不同长历时暴雨与总降雨事件的空间分异特征对比研究

长历时强降雨事件所导致的城市内涝已经成为当前中国城市安全建设和发展的严峻问题，因此，研究不同长历时强降雨事件空间演变特征具有重要的意义。采用1961~2017年中国545个日值气象站点降水数据，从雨量和雨日2个属性，分析不同长历时暴雨和总降雨事件的总量特征、变化趋势和年际变率空间分异格局。结果表明：(1)中国不同长历时暴雨和总降雨事件均呈东南高-西北低的空间分异格局，且随着降雨历时的增加，量级较高的不同长历时暴雨和总降雨事件在空间分布上逐渐向东南沿海地区集聚，且空间高低分异特征逐渐趋于减小。在华西秋雨的影响下，华西地区总降雨雨日相比同纬度其它地区较高。(2)中国不同长历时暴雨雨量和雨日主要在东南地区呈增加趋势，西北地区增减不明显。总降雨雨量变化趋势在东南和西北呈增加趋势，而在两者中间过渡带呈减少趋势，且随着降雨历时增加，减少趋势地带向东南和西北地区扩张。不同长历时总降雨雨日变化趋势则呈南方减少北方增加态势。(3)中国历时2 d的暴雨雨量和雨日年际变率在农牧交错带及其毗邻地区最大，而历时3 d以上的暴雨雨量和雨日年际变率则呈东南大-西北的分异格局。中国不同长历时总降雨雨量和雨日年际变率整体上呈南高-方低的分异格局，且随着降雨历时的增加，年际变率较大的地区向中国南部地区扩张。

Comparative Study on Spatial Differentiation Characteristics of Different Long Duration Heavy Rainfall and Total Rainfall Events in China from 1961 to 2017

Urban waterlogging caused by long duration heavy rainfall events has become a serious problem in urban safety construction and development in China. Therefore, it is of great significance to study the spatial evolution characteristics of different long duration heavy rainfall events. In this study, the precipitation datasets of 545 meteorological stations in China during 1961-2017 years were collected. From two attributes of rainfall amounts and rainfall days, the aggregate characteristics, trend and interannual variability to analyze the spatial pattern of different long duration heavy rainfall and total rainfall events. The results showed that: Firstly, the spatial pattern of different long duration heavy rainfall and total rainfall events over in China were higher in the Southeast China than in the Northwest China. With the increasing of rainfall duration, the spatial distribution of different long duration heavy rainfall events and total rainfall events with higher magnitude gradually converged to the southeastern coastal areas, and the spatial differentiation characteristics tended to decrease. Under the influence of autumn rainfall in the West China, the total rainfall amounts and days in the West China are higher than those in other regions of the same latitude. Secondly, different long duration heavy rainfall amounts and days in China were increasing mainly in the Southeast China, but not in the Northwest China. The trend of total rainfall amounts was increasing in the Southeast and Northwest China, but decreasing in the transitional zone between them. With the increasing of rainfall duration, the decreasing trend zone extended to the Southeast China and Northwest China. The trend of total rainfall days in different duration was increasing in the North China and decreasing in the South China. Thirdly, the interannual variability of heavy rainfall amounts and days over 2 days in China were the greatest in the ecotone between agriculture and animal husbandry and its vicinity, while the interannual variability of heavy rainfall amounts and days over 3 days are high in the Southeast China and low in the Northwest China. The interannual variability of total rainfall amounts and days are mainly high in the South China and low in the North China, and with the increasing of rainfall duration, the region with greater interannual variability expanded from North China to South China.