昆明市气候时空变化及其影响因素

以低纬高原城市昆明市为研究区域,利用昆明市近30年(1978—2015)的年平均气温数据,采用回归分析、滑动平均法和Mann-Kendall检验法分析昆明地区气温的年代际变化以及跃变;采用趋势拟合和相关分析,分析年平均气温与城市人口、GDP、建成区面积3项城市发展指标之间的关系。研究结果表明:(1)近30年来,昆明市的年平均气温呈波动上升趋势,增温率为0.55℃/10 a。(2)通过滑动平均法检测出昆明的气温跃变年份为1992年,通过Mann-Kendall突变检验得昆明的气温跃变年份为1994年,即昆明气温跃变时间为20世纪90年代初。(3)昆明各项城市发展指标都与气温变化成呈相关关系,表明它们与昆明气温变化关系密切。总的来说,人口和建成区面积是城市气温变化最主要的驱动因素,GDP也具有重要影响。

三峡库区近50年来的气温变化趋势

利用三峡库区及周边32个气象站点1960～2006年的气温资料,运用线性趋势分析、累积距平分析和t检验等统计学方法研究了三峡库区近50a来的气温变化趋势。研究结果表明:(1)近50a来三峡库区气温变化总体上呈显著上升趋势,增温率为0.13℃/10a;其中1960’s～1980’s末存在一个缓慢降温过程,1980’s末后快速增温。(2)三峡库区各季节平均气温变化过程与年气温变化过程相似,总体上也呈上升趋势,春、夏、秋、冬四季平均气温增温率分别为0.10、0.005、0.19和0.21℃/10a,其中冬季气温上升对库区年平均气温上升的贡献率最大。(3)年均气温跃变出现在1996年,春、夏、秋、冬四季气温跃变点分别出现在1996、1993、1997、1996年,季节气温的跃变与年均气温跃变具有较好的同步性。(4)三峡库区偏暖和显著偏暖年份都发生在1996年以后,其中1998和2006年为异常偏暖年份;偏冷年份基本出现在1990’s以前,尤其集中在1980’s,但无显著偏冷和异常偏冷年份。

RECENT TRENDS OF TEMPERATURE AND PRECIPITATION DISTURBED BY LARGE-SCALE RECLAMATION IN THE SANGJIANG PLAIN OF CHINA

The regional observed temperature and precipitation changes and their abruptjumps disturbed by large-scale reclamation in the Sanjiang Plain, Northeast China were studied. Meanannual temperature of the region was tending to go up and has increased by 1.2-2.2℃ over the past50 years. A warming jump of mean annual temperature of the region occurred in the 1980s, which hadan increasg amplitude of 0.9℃. Linear tendency rates of annual precipitation were negative in mostof the region. The maximum of annual precipitation decrease was 155.8mm over the past 50 years. Anabrupt decrease of regional annual precipitation happened in the middle of the 1960s, which had adecrease of 102.1mm. Based on the fact of climatic change of the Sanjiang Plain over the past 50years, it is held that the region had larger warming amplitude than that of the surrounding areas inthe recent years, which resulted from the large-scale reclamation of various kinds of wetlands.