不同类型El Nio事件对黑潮流域影响的统计分析

Statistical Analysis on the Influence of Different Types of El Nio in Kuroshio Region

利用全球海表面温度、海面流速、海平面异常、降雨和海面风场融合及再分析资料,采用相关分析和合成分析统计诊断方法,对1979-2014年发生的东太平洋和中太平洋El Nio事件对黑潮流域的影响进行分析,为黑潮流域及我国东南部气候变化预测提供参考。研究结果表明:前者对海表面温度的影响要比后者强烈,并经历了从降温到升温的效应转换;两者对黑潮流域海流流速的影响整体上呈相反状态,前者对东海PN断面海流流速起减缓作用,而后者对其流速起加速作用;对于黑潮流域的海平面异常,两者均没有明显的规律性影响;前者会引起黑潮流域降水增多,而后者则会引起黑潮流域降水减少。因此,东太平洋和中太平洋El Nio事件对黑潮流域的影响具有明显的差异。

Based on reanalysis data of sea surface temperature, sea surface current, sea level anomaly, precipitation and sea surface wind, correlation analysis and composite analysis are used to study the influence of Eastern Pacific （EP） and Central Pacific （CP） El Nino in the Kuroshio region from 1979 to 2014. This study provides statistical basis for the prediction of climate variations in Kuroshio region and southeastern China. The results show that the EP El Nino has stronger effect on SST variation in Kuroshio region than the CP El Nino, in which the SST anomaly experiences transition from cooling to warming. Impacts of these two types of El Nino on surface current are opposite, the current along the PN section in the East China Sea is weakened during EP El Nino but strengthened during CP El Nino. Both types of El Nino have no significant influence on SLA in this region. Precipitation in Kuroshio region increases during EP El Nino but decreases during CP El Nino. These results suggest that these two types of El Nino have significantly different impacts in the Kuroshio region.