The authors present the first synoptic characterisation of an oceanic mesoscale eddy’s full life cycle using groundbreaking SWOT satellite altimetry. This unprecedented view challenges the long-standing perception of eddies as simple, elliptical structures, revealing the crucial role of mesoscale interactions in their evolution. The SWOT results capture intense submesoscale turbulence at the eddy’s rim, exposing secondary instabilities that likely drive its dissipation. These findings not only validate decades of vortex theory but also open new frontiers in our understanding of oceanic turbulence.

Sea water thermodynamics is arguably one of the most central and fundamental areas concerning oceanography: how should we measure/interpret something as basic as temperature, salinity, heat and/or energy of sea water? The review is a tour de force by one of the leading experts of the subject area, summarising the development of sea water thermodynamics to date (spanning the author's career), highlights important subtleties that oceanographers should know, and provides interesting outlooks for further directions for investigation. Make no mistake, the review is by no means an easy or a short read, and the material will require time and effort to digest properly. This is likely one of those journeys where there simply is no shortcut, but this is an excellent guide to help those willing to undertake that journey.

This is an interesting study using a large rotating tank in the laboratory to simulate the flow through the Strait of Gibraltar. Laboratory experiments in geophysical fluid dynamics are increasingly rare, yet are highly visual and stimulating. The results are of high impact for understanding the processes such as tides determining the exchange between the Mediterranean and the Atlantic.

The sea surface microlayer (SML) is the thin layer on top of the ocean that is in direct contact with the atmosphere which is crucial for air–sea interactions. A novel paper shows data profiles close to the water surface in a mesocosm experiment. Using microsensor profiles at high vertical resolution, it shows dissolved oxygen and temperature gradients from the air, through the sea surface microlayer and into the water below. Phytoplankton bloom dynamics and surfactant concentrations influence the oxygen concentration and the diffusive layer depth but not temperature gradients. This has implications for air-sea exchanges across the sea surface microlayer.