中文摘要：

北宋开封地区的气候，绝大部分时间表现为继唐代以来我国气候变迁史上第三个温暖期的延续。其转变为第三个寒冷期的时间不是如近几十年来学者们承竺可桢所说的北宋前期，而是在北宋后期的徽宗初年。建中靖国元年前后，该地气候突然发生明显变化而进入了新的寒冷期。其间尽管这里的气候在徽宗、钦宗年间曾出现过由温暖期向寒冷期的突变，但总体上是一个渐进的变化过程。在当时每一段温暖期与另一段寒冷期气候交替变化的周期中，每一个较长时间的气候变化周期内都有若干个气候暖、冷交替变化的短周期，甚至在每一个短的气候暖、冷变化的周期内还有一些特别偏寒冷或偏温暖的年份。

英文摘要：

The climate in Kaifeng district in the Northern Song Dynasty is the extension to the third Warm Stage following the Tang Dynasty in the history of climate vicissitudes in China. However, the changing period of the third Cold Stage, which is explained that existed in the early period of the Song Dynasty according to Zhu Kezhen, does happen in the period of Huizong Monarch. The climate, which had changed in Huizong and Qinzong periods, is changing dramatically into a new cold stage in this district. At that time, the climate alternated between Warm Stage and Cold Stage, including several alternative short periods. In each climate changing period, each long period includes several short periods during which the temperature is changing alternately, and the changing period is a year which is cold or warm evidently.