Using the hourly precipitation records of meteorological stations in Shanghai, covering a period of almost a century （1916-2014）, the long-term variation of extreme heavy precipitation in Shanghai on multiple spatia...Using the hourly precipitation records of meteorological stations in Shanghai, covering a period of almost a century （1916-2014）, the long-term variation of extreme heavy precipitation in Shanghai on multiple spatial and temporal scales is analyzed, and the effects of urbanization on hourly rainstorms studied. Results show that： （1） Over the last century, extreme hourly precipitation events enhanced significantly. During the recent urbanization period from 1981 to 2014, the frequency of heavy precipitation increased significantly, with a distinct localized and abrupt characteristic. （2） The spatial distribution of long-term trends for the occurrence frequency and total precipitation intensity of hourly heavy precipitation in Shanghai shows a distinct urban rain-island feature; namely, heavy precipitation was increasingly focused in urban and suburban areas. Attribution analysis shows that urbanization in Shanghai contributed greatly to the increase in both frequency and intensity of heavy rainfall events in the city, thus leading to an increasing total precipitation amount of heavy rainfall events. In addition, the diurnal variation of rainfall intensity also shows distinctive urban-rural differences, especially during late afternoon and early nighttime in the city area. （3） Regional warming, with subsequent enhancement of water vapor content, convergence of moisture flux and atmospheric instability, provided favorable physical backgrounds for the formation of extreme precipitation. This accounts for the consistent increase in hourly heavy precipitation over the whole Shanghai area during recent times.展开更多
利用印江县气象观测站1983—2016年和区域内16个自动气象观测站2011—2016年汛期(4—9月)逐时降水观测资料,采用相关对比分析、汇总归类等统计方法,分析近34a县中心城区的短时强降水特征和近6 a 16个站的短时强降水时空分布特征。结果表...利用印江县气象观测站1983—2016年和区域内16个自动气象观测站2011—2016年汛期(4—9月)逐时降水观测资料,采用相关对比分析、汇总归类等统计方法,分析近34a县中心城区的短时强降水特征和近6 a 16个站的短时强降水时空分布特征。结果表明:(1)近34 a,县中心城区汛期短时强降水量级以20~30 mm为主,对暴雨日贡献比较大,年次数呈波动变化;集中并均匀分布在5—8月;日次数集中在夜间,日变化特征在各月有明显不同。(2)近6 a,印江区域内汛期短时强降水多发生在中东部,月份分布似正态分布,集中在6月和7月,各月不同区域累积次数也不同;日次数集中在夜间,日变化特征在各月也有明显不同。(3)利用得到的降水分布特征,指导印江气象局更好的开展"三个叫应"气象服务,重点关注短时强降水易发区、大小流域区域、地质灾害点和人口密集区。展开更多
基金jointly supported by the Major Consulting Projects of the Chinese Academy of Engineering(“Study on Strategies and Measures for the Prevention and Control of Urban Flood and Waterlogging Disasters in China”)the Public Welfare Industry(Meteorological)Research Projects(Grant Nos.GYHY201306065,GYHY201406001)a research project of the Shanghai Meteorological Bureau(Grant No.YJ201604)
文摘Using the hourly precipitation records of meteorological stations in Shanghai, covering a period of almost a century （1916-2014）, the long-term variation of extreme heavy precipitation in Shanghai on multiple spatial and temporal scales is analyzed, and the effects of urbanization on hourly rainstorms studied. Results show that： （1） Over the last century, extreme hourly precipitation events enhanced significantly. During the recent urbanization period from 1981 to 2014, the frequency of heavy precipitation increased significantly, with a distinct localized and abrupt characteristic. （2） The spatial distribution of long-term trends for the occurrence frequency and total precipitation intensity of hourly heavy precipitation in Shanghai shows a distinct urban rain-island feature; namely, heavy precipitation was increasingly focused in urban and suburban areas. Attribution analysis shows that urbanization in Shanghai contributed greatly to the increase in both frequency and intensity of heavy rainfall events in the city, thus leading to an increasing total precipitation amount of heavy rainfall events. In addition, the diurnal variation of rainfall intensity also shows distinctive urban-rural differences, especially during late afternoon and early nighttime in the city area. （3） Regional warming, with subsequent enhancement of water vapor content, convergence of moisture flux and atmospheric instability, provided favorable physical backgrounds for the formation of extreme precipitation. This accounts for the consistent increase in hourly heavy precipitation over the whole Shanghai area during recent times.
