北京夏季高温闷热天气的气候特征和2008夏季奥运会

利用1951～2000年北京6、7、8月的逐日最高和最低温度资料，统计分析了北京夏季高温天气和闷热天气的逐月、旬、候的分布及持续时间。结果表明，北京夏季高温天气和闷热天气发生概率分别为1／10和1／20，是一个适宜举办奥运会的城市。高温天气主要集中在6月下旬和7月份，逐候分布呈双峰型，分别在6月第6候和7月第5候。闷热天气主要集中在7月中旬到8月上旬，逐候分布也呈双峰型，分别在7月第6候和8月第2候。6月份高温天气较多，但闷热天气很少。8月份高温日数非常稀少，但闷热天气日数还有一定数量。每年至少出现一次持续2天的高温天气，另外还非常有可能出现一次持续3天或3天以上的高温天气(0．84次／年)以及一次2天及2天以上的持续闷热天气(0．88次／年)。高温天气和闷热天气的平均持续日数均约为3天。8月中、下旬，高温天气和闷热天气出现的概率都非常小，是最适宜举办夏季奥运会的时期。

Climatic Characteristics of Estival Muggy Weather in Beijing Related to 2008 Olympics

The characteristics, including the distribution in a month and the duration of Beijing estival muggy weather, is gained here by analyzing the daily maximum and minimum temperature in summer season(June, July and August) from 1951 to 2000. It revealed that the occurrence probabilities of the hot and muggy weather during the summer in Beijing are, respectively,1/10 and 1/20, which indicates Beijing is a suitable city for the Summer Olympic Games. The hot weather mainly occurs in late June and the whole July, with two maximum frequencies in the period of 26 to 30 June and 21 to 25 July, respectively. The muggy weather mainly occurs in the middle of July and early August, with two maximum frequencies in the period of 26-31 July and 6-10 August, respectively. There are many hot weather days but few muggy weather days in June . And there are very few hot weather days but several muggy days in August. The hot weather lasting more than 2 days occurs at least once a year. The occurrence frequencies of the hot and muggy weather lasting more than 3 days are 0.84 times/ year and 0.88 times/year respectively. The average duration of the hot and muggy weather are both 3 days. In the middle and late August, the hot and muggy weather seldom occur. That time is a good period for holding the Olympic Games.