应用JEDAC海温和SODA再分析资料,分析研究了西太平洋暖池(WPWP)的热状况变化特征,探讨了WPWP的热含量变化与不同深度海温变化,特别是与表层和次表层海温场之间的内在联系,分析研究了WPWP异常海温东传过程中与温跃层变化之间的关系,最后讨论了赤道潜流在异常海温东传过程的作用。结果表明,WPWP区域的热含量变化与次表层的海温变化具有相同变化趋势。WPWP区域的热含量变化与次表层海温达到(超过)99.9%信度检验的相关出现在次表层海温变化超前热含量变化的12个月至次表层海温变化滞后热含量变化12个月,最佳相关出现在同期,相关系数r=0.92(样本n=552)。WPWP区域的热含量变化与SST达到99.9%信度检验的相关只出现在热含量滞后SST5个月至同期。这一结果表明,WPWP区域的热含量变化主要体现了次表层海温场的变化特征。由此认为,WPWP区域热含量变化(次表层海温场)对气候变化的贡献主要体现在东向传播对ENSO的贡献上。由WPWP异常海温沿赤道东传过程和温跃层变化之间的关系可知,温跃层变化滞后于WPWP区域东传的异常海温,在WPWP区域异常海温东传过程中,赤道潜流起了重要作用。
Based on the reanalysis of JEDAC datasets and the assimilation of SODA, the authors studied the variation of the heat status in the West Pacific Warm pool (WPWP) and discussed the ocean temperature variety in the heat content at different depths, the inherent relations between ocean temperatures at surface and subsurface, the eastward propagation of anomalous ocean temperature and the thermocline variation, and the influence of equatorial undercurrent (EUC) on the eastward propagation. The result indicates that the variation tendency of heat storage is the same as that of subsurface ocean temperature. The correlation result has shown the variation at the subsurface ocean temperature led that of heat storage by 12 months, and lagged that of SST by 12 months. The SST variation lagged behind that of the heat storage by 5 months. These results indicate that the heat storage variation reflects mostly the variation at the subsurface ocean temperature in WPWP. It is therefore believed that the contribution of the variation of the heat storage (in subsurface ocean temperature field) in WPWP to climate change is mostly shown in the eastward propagation and then the influence on ENSO. The relation between the eastward propagation of the ocean temperature anomalies and the thermocline variation along the equator tells that the temperature variation at thermocline lags behind the eastward propagation during which the EUC plays an important role.