2013-2020年太平洋快速增暖现象的辨识与时空特征研究

Rapid warming of the Pacific during 2013-2020:identification and spatial-temporal characteristics

利用基于Argo的多套次表层温盐观测数据,本文分析了2004-2020年太平洋0~1500 m海洋热含量的变化趋势。研究发现,太平洋海洋热含量在2013年出现长期趋势的转变。2013-2020年太平洋海洋热含量相对于2004-2012年快速增加,前者线性趋势达到约0.50×10^(22)J/a,显著高于后者。近期太平洋出现了快速增暖现象。2013-2020年间,太平洋海洋热含量线性增加趋势最大出现在北太平洋西部,其次是热带太平洋和北太平洋东部,而整个南太平洋海洋热含量呈略微减少趋势。在北太平洋西部,海洋热含量快速增加集中在黑潮延伸体海域,该增暖趋势很可能是由黑潮延伸体主轴北移引起的。值得一提的是,日本以南出现了局地海洋热含量减少趋势,该变冷趋势与黑潮大弯曲不断加深有关。在增暖趋势次之的热带太平洋,海洋热含量的快速增加很可能是由温跃层快速加深导致的。此外,太平洋快速增暖反映在海表高度快速升高之中。1 cm/a的海表高度线性趋势对应于0.11×10^(9)J/(m^(2)·a)的海洋热含量线性趋势。本研究揭示了全球变暖停滞结束以来太平洋快速增暖现象,加深了对近期太平洋热力状况的认识。

Using multiple observational subsurface temperature and salinity datasets based on Argo,we analyze the trend of 0-1500 m ocean heat content in the Pacific between 2004 and 2020.It was found that the long-term trend of the Pacific ocean heat content showed a shift in 2013.The ocean heat content in 2013-2020 increased rapidly compared with that in 2004-2012.The linear trend of the former reaches about 0.50×10^(22) J/a,which is significantly higher than that of the latter.The Pacific has recently experienced rapid warming.During 2013-2020,the largest linear trend of the ocean heat content in the Pacific appeared in the western North Pacific,followed by the Tropical Pacific and eastern North Pacific.While the ocean heat content in the entire South Pacific showed a slightly decreasing trend.In the western North Pacific,the rapid increase of ocean heat content was concentrated in the Kuroshio Extension areas,and this warming trend is likely to be caused by the northward shift of the Kuroshio Extension main axis.It is worth mentioning that there was a local decreasing trend of ocean heat content in the sea south of Japan,and this cooling trend is associated with the strengthening of the Kuroshio large meander.In the Tropical Pacific where the warming trend is the second largest,the rapid increase of ocean heat content is likely to be induced by the thermocline deepening.In addition,we point out that the rapid warming in the Pacific is reflected by the rapid rise of sea level.The linear trend of sea level per 1 cm/a corresponds to the linear trend of ocean heat content of 0.11×10^(9) J/(m^(2)·a).This study elucidates the rapid warming of the Pacific since the end of the global warming hiatus,deepening our understanding of recent thermal conditions in the Pacific.