青藏高原四季开始日期随海拔高度和纬度变化

利用中国气象局国家气象信息中心提供的青藏高原60个测站1961～2007年逐日气温资料,分析了青藏高原近47年来四季开始日期随海拔高度和纬度的变化趋势。结果表明,春季和夏季开始日期是整体提前,而秋季和冬季开始日期是整体延迟的,春季和冬季开始日期的变化相对夏季和秋季更为明显;四季开始日期随海拔高度变化分布明显不同,海拔越高,春夏季开始日期来临越晚,秋冬季开始日期来临越早,海拔越低,春夏季开始日期来临越早,秋冬季开始日期来临越晚;海拔越高,春夏开始日期提前的天数越多,秋冬开始日期推迟天数越多,反之低海拔地区相对更小,由此得知高海拔地区的季节开始日期对当地气温的增温更为敏感;春季开始日期在36°N以南基本随纬度递增而开始日期推后,36°N以北地区春季相对偏早,夏季、秋季、冬季开始日期随纬度的变化和春季变化基本相似;四季开始日期来临的早晚受到多种因素包括气温、海拔和纬度共同影响,季节延迟率也受到气温和海拔的影响,但是纬度对季节延迟率影响不大;四季开始日期的提前和延迟变化和当地气温的变化几乎一致,秋冬季节的开始日期对气温变化更为敏感,高海拔地区的季节开始日期对气温变化更为敏感。

Research on the Relationships between the Beginning Data of Seasons and the Change of Altitude and Latitude

In this article, daily temperature data of 60 stations on the Tibet Plateau during 1961 -2007, which is applied by the National Meteorological Information Center of China Meteorological Administration, was used to analyzed the start datag change with altitude and latitude. The results show that, the beginning date of spring and summer is the advance overall, and the beginning date of autumn and winter is delayed, the change of spring and winter is obvious. At high altitude, the beginning date of spring and summer comes late, but the beginning date of autumn and winter behaves in opposite, the lower the altitude, the beginning date of spring and summer is coming sooner, the beginning date of autumn and winter comes too late; at higher altitudes, the more the beginning dates of spring and summer advanced, the more the beginning date of autumn and winter de- layed, and the changes of low altitude areas are relatively smaller, so, the beginning date of seasons at high altitude is more sensitive to the local temperature ; to the south of 36 ~ N, the beginning date of spring pushes back with latitude, to the north of 36 o N, which is relatively early in spring, summer, autumn, winter. The factors including temperature, altitude and lati- tude affect the beginning date of the seasons ; the beginning date of the seasons is coherent with local temperature.