南京地区降水结构时空演变特征

Temporal and Spatial Evolution Characteristics of Precipitation Structure in Nanjing Region

为研究南京地区降水结构时空演变规律,本文选取南京地区7个雨量站点1973—2021年的逐日降水资料,采用降水发生率和贡献率指标,利用Mann-Kendall法进行变化趋势检验,分析南京地区不同历时、不同等级降水结构的时空变化规律。结果表明,南京地区降水发生率随降水等级的增加而降低,各等级降水贡献率分布较为均衡;降水发生率及贡献率随降水历时的增加呈先增加后减小再增加的趋势,短历时降水发生率和贡献率呈由南向北逐渐增加的趋势。

To investigate the temporal and spatial evolution patterns of precipitation structure in the Nanjing region,this paper utilizes daily precipitation data from seven rainfall stations in Nanjing from 1973 to 2021.By using precipitation occurrence rate and contribution rate indicators,the Mann-Kendall test is applied to analyze the temporal and spatial variations of precipitation structure across different duration and intensity levels in Nanjing region.The results indicate that the precipitation occurrence rate decreases with increasing precipitation intensity levels,and the contribution rates of different intensity levels are relatively evenly distributed.Moreover,the precipitation occurrence rate and contribution rate exhibit a trend of initially increasing,then decreasing,and increasing again with the increase of precipitation duration.Additionally,the occurrence rate and contribution rate of short-duration precipitation show a gradual increase from south to north.