气候变暖背景下清远气温变化特征

根据1957—2007年清远站的年和月平均气温资料,采用线性倾向的最小二乘法估计分析季及年平均气温的变化趋势。结果表明:在气候变暖背景下,近50 a清远年平均气温存在与全球、中国及广东省同步的增暖趋势,增暖幅度(平均气温线性增暖速率为0.17℃/10 a)高于近50 a全球平均线性增暖速率,低于近50 a中国及广东省平均线性增暖速率。四季及年平均气温在变暖趋势上基本同步,只有冬季稍落后。且在气候变暖背景下,清远异常冷、暖冬事件出现频繁,暖冬明显。应用Mann-Kendall法检测气候的突变性,表明清远冬季平均气温于1968年前后存在由低向高的突变。

Characteristics of air temperature in Qingyuan,Guangdong province

Based on the annual and monthly average air temperatures data from 1957 to 2007 in Qingyuan weather station,the change trends and characteristics of annual and seasonal average air temperatures were analyzed by linear tendency of least squares method.The results show that annual average air temperature takes on an increase trend in Qingyuan during recent 50 a,which is synchronous to those in the globe,China and Guangdong province.The ratio of warming is 017 ℃/10 a,and it is higher than that in the globe and lower than those in China and Guangdong province during recent 50 a.The warming trends of seasonal and annual average air temperatures are synchronous,while the trends in winter lag lightly.Events of the abnormal cold and warm winters occur frequently,and the warm winter is obvious.An abrupt change of winter average air temperature from high to low appears in 1968 according to the determination of Mann-Kendall method.