黑潮弯曲时的北太平洋冬季海温异常对大气低频振荡的影响

THE EFFECT OF THE SST ANOMALY IN THE NORTH PACIFIC DUE TO THE MEANDER OF THE KUROSHIO IN WINTER ON THE LOW FREQUENCY OSCILLATION

利用中科院大气物理研究所开放实验室ＩＡＰ－ＡＧＣＭ（二层大气环流模式），针对黑潮弯曲时的北太平洋冬季表层海温（ＳＳＴ）异常进行八个月的数值积分试验。试验结果表明：黑潮弯曲时北太平洋冬季ＳＳＴ异常对大气低频振荡的影响具有明显的３０－６０ｄ振荡的特征；在北半球的３０－６０ｄ振荡，大部分地区为向西传播，在南半球则为向东传播；其经向传播较为复杂，在１２０°Ｅ剖面上以向南传播为主；热带地区受此ＳＳＴ异常的影响以西太平洋、印度洋大气加热场的３０－６０ｄ振荡为主要标志。

A numerical integration experiment was carried out on the Sea Surface Temperature (SST) anomaly in the North Pacific corresponding to the meander of the Kuroshio in winter(January-March) by using a two-layer global atmospheric general circulation model (IAP-AGCM). The experiment showed that the SST anomaly in the North Pacific in winter could induce a 30- 60 day oscillation in the global atmosphere. The direction of the oscillation propagation along the latitude and the longitude is different in different hemispheres. In the tropical zone, the 30- 60 day oscillation of the atmospheric heating field is induced. The low frequency oscillation affects the global circulation through a 2-dimensional Rossby wave train.