北京极端低温事件的长期变化特征

The Long-Term Change Features of Climatic Extreme Events for Daily Minimum Temperature in Beijing

利用1951—2008年北京逐日最低气温资料和新的气候极端事件阈值计算方法,对北京地区最低气温第10百分位阈值进行了计算,并分析了最低气温极端气候事件出现频率和寒冷程度的年际和年代际变化。结果表明,北京比较寒冷事件发生的频率和寒冷程度存在年代际变化,其变化趋势呈减少或减弱趋势,且在21世纪初发生了转变。北京地区最低气温的年代际变化存在13.3年和2.1年的主要变化周期。

Using the daily minimum temperature data in Beijing during 1951-2010 and the new meth- od of computing the threshold value of the climatic extreme event, the 10th percentile threshold value for minimum temperature in Beijing were calculated, and the interannual and interdecadal changes of the occurrence frequency of the extreme low temperature events were studied. The results show that the oc- currence frequency and the degree of the extreme cold events have obviously decreasing tendency in Bei- jing, but have changes in the early of the 21st century. It also shows that they have the interdecadal and decadal variations. The main periods of their variation are 13.3 and 2.1 years.