中低纬海气相互作用的耦合模态变化研究

利用1948—2003年的NCEP再分析资料和英国气象局Hadley气候预测和研究中心的海表面温度资料，从整体分析地球中低纬三大洋海气耦合系统的角度出发，使用SVD方法研究中低纬海气相互作用的耦合变化。结果表明，中低纬海气相互作用是一个有机的耦合整体，其变化不管从年际还是年代际上都存在耦合相关性，这一点给我们提出了一个新的研究全球范围海气耦合变化的思路。提取的海气耦合基本模态的正、负异常年份的海温和风场异常合成分析结果显示，当赤道东太平洋的海水偏暖时，热带印度洋和热带大西洋的海水也偏暖，热带西太平洋直至中纬度太平洋的海温总体偏冷。就印度洋而言非洲大陆以南30~50 °S的大片海区存在明显的海温负异常。北美洲大陆的东岸30 °N以北和南美洲大陆的东岸30 °S以南的海区都为明显的海温负异常。当赤道东太平洋的海水偏冷时各大海区的海温分布情况反之。 

MID-LOW LATITUDE AIR-SEA INTERACTION IN THE COUPLING CHANGES

Using the NCEP/NCAR reanalysis data, the sea surface temperature (SST) data of Hadley Center /the United Kingdom Meteorological Office during 1948 to 2003 and singular value decomposition (SVD) method, we investigate the leading coupled modes between the SST anomalies and the atmospheric circulation anomalies in the East Asia-subtropical North Pacific region. The results show that the global mid-low latitude air-sea interaction is the coupling of an organic whole, regardless of its annual or decadal change there is synchronized coupling. This also gives us a new idea of global changes in air-sea coupling. The results of extracted composite analysis of SST anomaly and wind anomaly of the basic air-sea coupled mode in positive and negative anomalous years show that when the sea water of the equatorial eastern Pacific is warm, the tropical Indian Ocean and tropical Atlantic sea water is simultaneously warm, while at the same time the SST of the area from the tropical western Pacific to mid-latitude Pacific is generally cool. The sea water in both of the east and west of the Pacific coast is generally warm. In terms of the Indian Ocean, the large sea area of 30~50 °S of the southern Africa has obvious negative SST anomalies. There are obvious negative SST anomalies in the sea areas north of 30 °N on the east coast of the North America and south of 30 °S on the east coast of the South America. When the SST of the eastern equatorial Pacific is cool, the reverse is true for the SST distribution of each of the oceans.