1961-2017年中国华东区域高空温度变化特征

Characteristics of upper-level air temperature over East China from 1961 to 2017

利用中国华东六省一市13个探空站1961-2017年高空温度数据,对850 h Pa、500 h Pa、200 h Pa高空温度的时间变化特征和空间变化特征进行分析,结果表明:1961-2017年中国华东区域对流层中下层增温趋势明显,向上增温趋势减弱,对流层顶增温趋势有所增强。850 h Pa、500 h Pa温度的年代际变化均呈现出先降低后升高的趋势,而200 h Pa温度的年代际变化则呈现持续升高的趋势。秋、冬季在各个层次上均为显著的增温趋势,冬季的增温趋势明显大于其他季节,500 h Pa春季和200 h Pa夏季有微弱的降温趋势。不同层次年平均气温的空间分布均有明显的南北差异,且随着高度的增加,南北平均温差先增大后减小。850 h Pa、500 h Pa年平均温度的空间变化趋势一定程度上呈现出华东沿海地区增温趋势大于内陆的特征,200 h Pa则呈现华东南部的增温趋势大于北部的特征。850 h Pa各季节呈现出中国华东沿海地区增温、内陆增温趋势不如沿海地区或内陆呈现降温趋势,500 h Pa的春季和200 h Pa的夏、秋季则呈现出中国华东南部地区增温、北部地区降温的趋势。

Based on upper-level air temperature radiosonde data obtained from 13 stations in East China( including six provinces and one city) from 1961 to 2017,we analyzed the spatiotemporal characteristics of upper-level air temperature at 850 hPa,500 hPa,and 200 hPa in this region. The results showed that an obvious warming trend can be observed in the middle-lower troposphere and at the troposphere top,and between them,such trend becomes weak gradually with increasing height. Annual mean upper-level air temperature at 850 h Pa and 500 hPa exhibits a "decrease first and then increase"variation,while it at 200 h Pa persistently increases during the studying period. During autumn and winter,air temperature at all levels shows a significant warming trend,most obviously in winter,whereas a weak cooling trend is observed at 500 h Pa in spring and 200 h Pa in summer. The spatial distribution of annual mean temperature at different levels differs from the north to the south. The temperature difference between the north and the south increases first and then decreases with the increase of height. Annual mean air temperature at 850 hPa and500 hPa has a stronger warming trend in the coastal area than in the inland area,while it at 200 hPa has a stronger warming trend in the southern area than in the northern area. In all seasons at 850 h Pa,the warming trend in the coastal area is stronger than that in the inland area,and sometimes the inland area even exhibits a cooling trend. In spring at 500 h Pa and summer and autumn at 200 hPa,a warming trend exhibits in the southern region,and a cooling trend is observed in the northern region in East China.