Research advances in oceanic mesoscale eddies

Oceanic mesoscale eddies are fundamental components of ocean dynamic systems, typically spanning tens to hundreds of kilometers and persisting for weeks to several months. As key dynamic features governing ocean energy distribution, these eddies regulate oceanic energy budgets, heat redistribution and material transport processes. Recent technological advancements have substantially expanded our understanding of oceanic mesoscale eddies, which could help inform future research paths to better understand and predict the eddies, according to a team of researchers based in China.

“The ocean is a complex dynamic system characterized by multiscale interactions, and mesoscale eddies are a key factor in the energy distribution within this system, exerting notable impacts on air-sea interactions and small-scale mixing processes,” said team lead Changming Dong, a professor at Nanjing University of Information Science & Technology.

The researchers published a review of the current body of scientific work on oceanic mesoscale eddies on Feb. 12 in Ocean-Land-Atmosphere Research. They identified and summarized six major areas of advancements in recent eddy research:

• Innovations in eddy detection technology, including automated systems
• A deeper understanding of the mechanisms behind eddy formation and dissipation, such as how they generate and why they break apart
• Breakthroughs in the study of energy cascade processes, when eddies transfer their energy to smaller scales
• New discoveries in mesoscale air-sea interactions, where the eddies can influence the air and vice versa
• The expansion of interdisciplinary research, which includes but is not limited to introducing the impacts of eddies on biogeochemistry and acoustics
• The achievements of specialized observation programs and collaborations to share and validate data

“These advancements collectively enhance our understanding of mesoscale eddies and their significant role in ocean dynamics and climate systems,” Dong said, explaining that technological advancements, such as improvements in satellite remote sensing and direct observation tools, have increased both the quality and quantity of research in the area. “As a result, we are now at a critical juncture where summarizing and consolidating research achievements in mesoscale eddy studies are essential.”

Based on the available data and research trends, Dong said the team identified four potential “hotspots” for future research: the stability of mesoscale eddies and their relation to subsequent submesoscale processes; how mesoscale eddies contribute to ocean circulation; impacts of mesoscale processes on the air-sea exchange, ecology, acoustics and what role these impacts play in climate change; computationally simulating and forecasting mesoscale eddies.

“Reflecting on the current state of mesoscale eddy research provides valuable insight for young researchers, helping them quickly grasp the key dynamics in this field and focus their efforts on promising areas for future breakthroughs,” Dong said. “This approach not only advances mesoscale eddy research but also lays a solid foundation for achieving significant innovations in the future.”  

Dong is also affiliated with the Southern Marine Science and Engineering Guangdong Laboratory. Other authors include Zhiwei You, Jihai Dong, Jinlin Ji, Wenjin Sun, Xiaojie Lu, Huarong Xie, Fangyuan Teng, Minghan Fu and Jin Wang, Nanjing University of Information Science & Technology; Guangjun Xu and Qiong Xia, Southern Marine Science and Engineering Guangdong Laboratory and Guangdong Ocean University; Yu Liu, Xiayan Lin and Guoqing Han, Zhejiang Ocean University; Anqi Xu, Key Laboratory of Ocean Observation and Forecasting and Key Laboratory of Ocean Circulation and Waves, Institute of Oceanology, Chinese Academy of Sciences; Qingyue Wang, Jiangsu Provincial Meteorological Service Center; and Yuhan Cao, Jiangsu Ocean University.

The National Natural Science Foundation of China and the Southern Marine and Engineering Guangdong Laboratory funded this research.