1892-2010年间重庆主城降水变化趋势分析

 针对近年来普遍存在的城市雨洪灾害问题，利用重庆市沙坪坝气象站1892—2010年的逐月降水量资料，采用线性倾向估计和方差分析法（ANOVA）分析了119 a来重庆主城不同统计时段的降水量及不同等级的降水频率，探讨了近百年来重庆市主城区域降水变化的趋势，以期为城市雨洪灾害防治及城市排水规划的决策提供科学指导。结果表明：119 a来，全年及汛期降水量稍有增加的趋势，年降水量增长向汛期趋于集中;此外，近30 a来，主城区域降水量年际变化幅度有明显的扩大趋势，较大等级降水的发生频率也明显增加;特别是最近10 a，该变幅更加剧烈，连续时段内灾害性气候的发生频率有增长趋势，加剧了城市汛期排水系统的压力。

Trend of Precipitation Variation in Main Urban Area of Chongqing City from 1892 to 2010

The present research aims to provide scientific basis for storm water disaster prevention and storm water drainage planning in urban area.Based on monthly precipitation data from 1892 to 2010 at Shapingba meteorological station in Chongqing,we analyzed the precipitation and the frequencies of different precipitation grading in different statistical periods in the past 119 years through linear trend estimation and analysis of variance(ANOVA).We also discussed the trend of precipitation variation in Chongqing urban area.Results showed that annual precipitation and precipitation in flood seasons increased slightly.Annual precipitation increase mainly concentrated in flood seasons.In addition,in the past three decades,the range of annual variation had an obvious expanding trend,and the frequencies of large precipitation also had been increasing significantly.Particularly in the recent decade,annual precipitation variation in urban area had been more intensive and the frequencies of catastrophic climate in continuous period had been increasing,which exacerbated the pressures on drainage system in flood seasons.