南海及周边地区春季海温年代际变化特征及其对印度太平洋地区气候的可能影响

Interdecadal variability of spring sea surface temperature in and around the South China Sea and its possible impact on climate in the Indo-Pacific region

为研究全球变暖背景下南海及周边地区春季气候主要特征、形成机制、季节变化趋势,利用经验正交函数(EOF)分解、线性倾向估计、滑动平均和相关分析等方法分析年代际背景下南海及周边地区春季海温主要模态及其对印度—太平洋地区同期春季气候的可能影响。结果表明,南海及周边地区春季海温异常呈现2种模态,第一模态为全区一致增暖,第二模态为北部冷而南部暖。第一模态海温分布受全球变暖影响显著,春季菲律宾海地区出现异常反气旋环流,副热带高压西侧加强,印度洋海盆在前一年冬季的一致增暖预示着次年春季南海及周边地区春季海温的一致增暖;第二模态受前一年冬季太平洋La Nina事件影响明显,南海海温异常在东亚沿岸激发出位势高度场正负相间的波列分布。第一(二)模态南海及周边地区降水呈现北涝(旱)南旱(涝)分布型。春季南海及周边地区海温异常将对印度—太平洋沿岸地区春季及夏季气候产生显著影响。

In order to study the main characteristics,formation mechanism and seasonal trends of spring climate in and around the South China Sea in the context of global warming,the main modes of spring sea temperature in and around the South China Sea in the context of the inter-generational context were analyzed,and their possible effects on spring climate in the Indian Ocean and the Pacific region during the same period were analyzed by the methods of empirical orthogonal function(EOF)decomposition,linear tendency estimation,sliding average and correlation analysis.The results show that in and around the South China Sea,the spring sea temperature anomaly presents two modes.The first mode is consistent warming in the region,and the second mode is cold in the north and warm in the south.The first modal sea temperature distribution is significantly affected by global warming.In the spring,there is an abnormal anti-cyclone circulation in the Philippine Sea area,and the western side of the subtropical high is strengthened.The consistent warming of the Indian Ocean basin in the previous winter indicate that the spring will be consistent warming in and around the South China Sea in the following spring.The second mode is obviously affected by the La Nina event in the pre-winter Pacific Ocean.The South China Sea temperature anomaly triggers a positive and negative wave distribution of the potential height field on the East Asian coast.The first(second)mode of precipitation in and around the South China Sea shows the distribution of waterlogging(drought)in the north and drought(waterlogging)in the south.The abnormal sea temperature in the South China Sea and its surrounding areas in spring will have a significant impact on the spring and summer climate in the India-Pacific coastal areas.