近50年长三角地区季节的气候变化特征

根据长三角地区31个站点1961-2010年逐日气温资料,按照国家标准进行季节划分,在研究四季长度和起始时间变化特征的基础上,利用Mann-Kendall检验、等值线等方法对季节的时间变化趋势和空间分布特征进行研究。结果表明,时间变化上,长三角地区夏季长度有极显著的增加趋势(P0.01),春、夏两季的起始日期有显著的提前趋势(P0.01和P0.05)。空间分布上,春、秋季节长度由内陆向沿海增加,夏季长度由北向南递增,冬季长度由北向南递减。四季长度变化趋势的空间结构为:春、夏季以延长为主,秋、冬季主要表现为缩短,其中夏季长度的延长最为显著(P0.01)。四季起始时间空间分布为:春、夏季南部入季早,秋、冬季北部入季早;起始时间变化趋势的空间结构为:春、夏季为一致的提早趋势;秋、冬季以延后为主。

Variation Characteristics of Seasons in the Yangtze River Delta during the Past 50 Years

Based on the daily temperature data of 31 weather observation stations from 1961 to 2010 in the Yangtze river delta, authors analyzed the variation characteristics of season length and starting date by using the trend analysis method, Mann- Kendall test method, and then analyzed the temporal and spatial distribution characteristics of seasonal climate variation by using the isoline technology. The temporal distribution results showed that the length of summer had a significant increasing trend（ P 〈 0. 01 ） , and the starting time of spring and summer had a significant advancing trend（ P 〈 0. 01 and P 〈 0. 05 ） during past 50 years in this study area. The spatial distribution results showed that the length of spring and autumn increased from inland to coast, the length of summer became longer from north to south and the length of winter became shorter from north to south. The spatial distribution showed that spring and summer became predominantly longer as while as autumn and winter became predominantly shorter, and the summer length changed most significantly （P 〈0. 01 ） ;the spring and winter started earlier in the north; and the starting dates of and summer had an advancing trend at many stations. and summer started earlier in the south, while autumn autumn and winter had a delaying trend while spring