杭嘉湖地区城市发展对降水影响的分析

Effect of Urbanization on Regional Precipitation in Hangzhou-Jiaxing-Huzhou Area

利用杭嘉湖地区长系列逐日降水资料,采用统计分析、线性回归、R/S分析、集中度和集中期等方法,探讨城市化发展条件下的降水变化规律。结果表明:随着城市化的快速发展,在年雨量、汛期雨量、大雨和暴雨日数上,杭嘉湖地区城区降水的增多趋势较郊区明显,城郊降水差距在增大,城市"增雨效应"显著;城郊年雨量的集中度均具有减少的趋势,但郊区递减速度稍大于城区;而冬季雨量则呈现出区域性特征,且城市化对小雨和中雨日数的影响仍具有一定的不确定性,反映出城市化对降雨影响的复杂性。

Taking daily rainfall data from 1961-2006 in Hangzhou-Jiaxing-Huzhou area and using statistical analysis,linear regression,R/S method,concentration degree and concentration period,this paper analyzes the effects of urbanization on the long term precipitation.The results show that with the development of urbanization,the increasing trend of annual precipitation,flood season precipitation,heavy rain days and storm rainfall days in urban areas is more than the suburban areas,the difference of urban and suburban areas is increasing and the urban precipitation increasing effect is evident.The precipitation concentration degree is on the decline in urban and suburban areas,and the rate of decrease in suburban areas is slightly more than urban areas.However,the winter precipitation shows the regional characteristics,the light rain days and moderate rain days are uncertain,reflecting the complexity of the impacts of urbanization on precipitation.