中文摘要：

利用中国气象局国家气象信息中心提供的中国599个测站1961～2007年逐日温度资料,分析了我国近47年来四季开始日期的变化趋势。结果表明,四季开始日期在全国范围内主要表现为春季、夏季提早,秋季、冬季推迟的变化趋势,其中以夏季的变化最为明显,且在显著增温的21世纪初最为明显。这种趋势在空间分布上有所差异,北方比南方明显,东部比西部明显。东北最北部、华南最南部以及新疆局部区域春季推迟,青海东部以及内蒙古最北部的小范围地区夏季推迟,华南及西南局部地区冬季提早。此外,全国平均四季开始日期的年代际变化在20世纪并不是很明显,而在21世纪初非常明显。但年代际变化特征存在区域性差异,高原地区20世纪80年代和90年代春季提早,冬季推迟。而在21世纪初春季、冬季均推迟,但冬季的变化比春季明显得多。华南南部地区春季推迟、冬季提早。西南地区在21世纪初春季、夏季明显提早,秋季、冬季推迟,但之前这种趋势并不明显。

英文摘要：

The variation trends of season start dates during recent 47 years were analyzed by using daily temperature data of 1961-2007 from 599 standard meteorological stations provided by the National Meteorological Information Center,China Meteorological Administration. The results show that the season start dates of spring and summer become earlier,of autumn and winter become later,of summer have the most obvious change,and this trend is the most evident in the beginning of the 21st century when the global warming is significant. This trend has different spatial distribution all over China,which is more evident in the north than in the south and more evident in the eastern part than in the western part. In the northernmost part of Northeast China,the southernmost part of South China and some areas of Xinjiang,spring become later; in small area of the east of Qinghai and the northernmost part of Inner Mongolia,summer become later; in some areas of East China and Southwest China,winter become earlier. And the decadal change in national average is not very obvious in the 20th century,but reverse in the beginning of the 21st century. The features of decadal change are not the same in different regions. In the plateau,there is earlier spring and later winter in the 1980s and the 1990s. In the beginning of the 21st century,both of spring and winter are late,but the change in winter is more obvious than in spring. In the south of South China,spring become later when winter become earlier. In the beginning of the 21st century,the trend that spring and summer become earlier is more obvious than the trend that autumn and winter become later in Southwest China.