南太平洋热带-副热带区斜压不稳定的多年代际趋势及其机制分析  

MECHANISM OF BAROCLINIC INSTABILITY AND MULTIDECADAL TREND IN SOUTH PACIFIC TROPICAL-SUBTROPICAL REGION

作　　者：刘丹丹 朱善良[1] 刘传玉[2,3] 冯岭 LIU Dan-Dan;ZHU Shan-Liang;LIU Chuan-Yu;FENG Ling(School of Mathematics and Physics,Qingdao University of Science and Technology,Qingdao 266061,China;Key Laboratory of Ocean Dynamic Processes Observation and Forecasting,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,China;Key Laboratory of Ocean Circulation and Waves,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,China)

机构地区：[1]青岛科技大学数理学院,山东青岛266061 [2]中国科学院海洋研究所海洋动力过程观测和预报重点实验室,山东青岛266071 [3]中国科学院海洋研究所海洋环流与波动重点实验室,山东青岛266071

出　　处：《海洋与湖沼》2025年第2期252-261,共10页Oceanologia Et Limnologia Sinica

基　　金：国家自然科学基金委重点项目,42430403号。

摘　　要：为了探究全球变暖对斜压不稳定的影响,本研究采用1°×1°的温度、盐度和流场格点数据,对1993~2022年南太平洋热带-副热带海区(south Pacific tropical-subtropical,SPTS)表层强化的Charney型斜压不稳定的长期变化趋势及其机制进行了分析。发现南太平洋热带区(south Pacific tropical,SPT)斜压不稳定的增长率表现出显著的减少趋势,每10 a减少0.12%,而南太平洋副热带区(South Pacific Subtropical,SPS)斜压不稳定的增长率则表现出显著的增加趋势,每10 a增加0.10%。上述增长率的变化趋势与卫星观测的涡旋动能(eddy kinetic energy,EKE)的变化趋势一致,且SPT的斜压不稳定的变化受剪切和层结的共同调控,而SPS的斜压不稳定的变化主要受剪切的影响,说明斜压不稳定性的变化体现了温盐和流场变化的综合效应。进一步分析发现,上述增长率及EKE的变化趋势与局地有效位能(available potential energy,APE)的趋势一致,突显了斜压不稳定性在能量转移转化中的关键作用。Using 1°×1°gridded data of temperature,salinity,and current fields,the long-term trend and mechanisms of surface-enhanced Charney-type baroclinic instability in the tropical-subtropical region of the South Pacific from 1993 to 2022 were analyzed.Results show that the growth rate in the tropical South Pacific(SPT)exhibited a significant decreasing trend,with a reduction of 0.12%per decade,while that in the subtropical South Pacific(SPS)showed a significant increasing trend,with an increase of 0.10%per decade.These trends are consistent with those observed in eddy kinetic energy(EKE)from satellite observations.The variation in baroclinic instability in the SPT was jointly regulated by shear and stratification,while that in the SPS was primarily influenced by shear,indicating that the variation in baroclinic instability is resulted from the combined effects of temperature,salinity,and current field.Further analysis revealed that the trends in growth rate and EKE were consistent with the trends in local available potential energy(APE),highlighting the critical role of baroclinic instability in energy transfer and conversion.

关 键 词：斜压不稳定 中尺度涡旋 涡动能 有效位能 

分 类 号：P731[天文地球—海洋科学]