东北冬季极端气温趋势变化及其城市化影响

利用我国东北地区90个气象站和5个乡村气象站1957～2010年日最高、最低气温资料，分南北两区分析了冬季极端气温事件的长期趋势变化特征，并评价了城市化因素对各极端气温指数趋势变化的影响。结果表明，东北地区暖夜日数、暖昼日数明显增加；冷夜日数、冷昼日数、冷日持续指数均呈显著减少趋势；日较差逐年减小，北区变化更大；其中冷夜日数减少最明显，北区以3．3d／10a的速率下降，南区减少速率为1．9d／10a。城市化对各种极端气温指数序列的趋势变化具有明显的影响，对冷指数序列趋势变化的影响比暖指教更大；城市化对冷夜日教、冷昼日数长期减少趋势的贡献率为35．79％和20．62％，对暖昼日数增加的贡献率为14．46％。

Regional Studies of the Extreme Temperature Changes in Northeast China and Their Response to Urbanization

Using maximum and minimum temperature data in Northeast China 90 weather stations and 5 rural weather station during 1957 - 2010, the variation features of long-term trend of wirrter extreme temperature events were analyzed, and the effects of urbanization factors on extreme temperalure index trend were evaluated. The results showed that warm night days, warm day and day number increase; cold night days, cold day number, cold days continuous index are showing a decreasing trend; cold night days decreased most obviously, the decrease rate of northern area is 3.3 d/10a, southern area is 1.9 d/10 a. Urbanization has obvious effects on trend variation of extreme temperature in- dex. The contribution rate of urbanization to cold night days, cold day number long-term decreasing trend is 35.79% and 20.62% , and the contribution rate to warm day number increasing is 14.46%.