摘要
海洋中广泛存在的中尺度涡旋对动量、能量、热量和物质传输起着至关重要的作用。详细介绍了利用卫星高度计资料识别中尺度涡的闭合等值线、Okubo-Weiss数、绕角和流矢量的方法。结果表明,绝大部分涡旋都呈近刚性旋转的非线性特征,生命周期大于等于16周涡旋的平均寿命、传播距离、振幅和半径分别为32周、550 km、8 cm和90 km。重点介绍了结合卫星高度计和Argo浮标资料合成中尺度涡三维结构的方法。受生成地和移动到当地海洋温盐背景场的共同作用,涡旋呈现不同的三维结构。从演变角度简单介绍了墨西哥湾的回流环和大西洋的地中海涡旋的基本特征。最后,对中尺度涡研究的难点问题,如次中尺度过程、中尺度涡能量耗散和次表层涡旋等进行讨论,并提出今后应从中尺度涡立体化、机动性观测,中尺度涡多学科融合式观测以及多尺度相互作用等方面开展突破性研究。
Mesoscale eddies,which are widely found in the oceans,play a vital role in momentum,energy,heat and mass transport.The Euler method for identifying mesoscale eddies using satellite altimeter data was presented in detail,including closed SLA contours,OW numbers,Winding-Angle and flow vector methods.The results show that mesoscale eddies are almost nonlinear and solid-body rotation.The long-lived eddies with lifetimes≥16 weeks have an average lifetime of 32 weeks and an average propagation distance of 550 km.Their mean amplitude and a speed-based radius scale as defined by the automated procedure are 8 cm and 90 km,respectively.The method combining with SLA and Argo profiles to composite the three-dimensional structure were addressed.Due to the different temperature and salt structure in the various oceans of the world,the eddies in different oceans show different three-dimensional structures,which are influenced by both the generation and local temperature and salinity.Two special types of eddies were introduced from the perspective of generation,evolution and dissipation processes,namely the Loop Current Ring in the Gulf of Mexico and Mediterranean eddy in the Atlantic Ocean.Finally,issues including submesoscale processes,dissipation of eddies and subthermocline eddies were discussed,and some future research directions were proposed.
作者
张永垂
王宁
周林
刘科峰
汪浩笛
Zhang Yongchui;Wang Ning;Zhou Lin;Liu Kefeng;Wang Haodi(College of Meteorology and Oceanography,National University of Defense Technology,Nanjing 211101,China;Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai),Zhuhai Guangdong 519082,China)
出处
《地球科学进展》
CAS
CSCD
北大核心
2020年第6期568-580,共13页
Advances in Earth Science
基金
国家重点研发计划项目“高分辨率海洋模式关键物理过程参数化方案的研发”(编号:2017YFA0604100)
国家自然科学基金项目“北太平洋副热带东西部海平面反相变化趋势和气候模态的相关关系研究”(编号:41406003)资助。
关键词
中尺度涡旋
表面特征
三维结构
回流环
地中海涡旋
Mesoscale eddies
Surface characteristics
Three-dimensional structure
Loop Current Ring
Mediterranean eddy
