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Thank you to the 1396 reviewers who provided 2328 reviews during 2023 to ensure the quality and integrity of JGR‐Oceans manuscripts. Key Point: Thank you to our 2023 peer reviewers [ABSTRACT FROM AUTHOR]

Plain Language Summary: Thank you to the 1528 reviewers who provided 2647 reviews during 2022 to ensure the high quality and integrity of JGR‐Oceans manuscripts. Key Points: The editors thank the 2022 peer reviewersNew editorial practices reduce pressure on reviewersCo‐reviewer tool allows collaboration with students and postdocs [ABSTRACT FROM AUTHOR]

JGR‐Oceans receives many more submissions from a broader demographic of authors than in the past and burnout among reviewers as well as potential bias among editors is threatening excellence and equity at the journal. To confront these issues, we have implemented some new editorial strategies that are anticipated to provide a fairer and more rewarding peer‐review experience for authors, as well as alleviate pressure on reviewers and deliver high quality science for readers. First, we have recruited a dozen new editors from across the world who better reflect our author demographic and who can make wiser and more inclusive decisions about the running of the journal. Second, we now require that each manuscript clearly communicate new understanding about the ocean before we send it out for review. This simple rubric deflects potentially biased editorial decisions based on author attributes and brings us closer to the original scope of JGR‐Oceans. Third, we are facilitating a culture of collaboration among reviewers and among ourselves, the editors, that brings more balanced decision‐making to reviews and manuscripts and provides authors more feedback. Our aim is to better help authors communicate their science with confidence and clarity. Finally, JGR‐Oceans has always been a multi‐disciplinary journal and we are encouraging more submissions that convey new understanding of biogeochemical processes and human interact ocean variability and change. Key Points: JGR‐Oceans has diversified the editorial board and implemented new editorial strategies [ABSTRACT FROM AUTHOR]

Observations from the global ocean have long confirmed the ubiquity of thermohaline inversions in the upper ocean, often accompanied by a clear signal in biogeochemical properties. Their emergence has been linked to different processes such as double diffusion, mesoscale stirring, frontal subduction, and the recently discussed submesoscale features. This study uses the central Baltic Sea as a natural laboratory to explore the formation of salinity inversions in the thermocline region during summer. We use realistic high‐resolution simulations complemented by field observations to identify the dominant generation mechanism and potential hotspots of their emergence. We propose that the strongly stratified thermocline can host distinct salinity minima during summer conditions resulting primarily from the interaction between lateral surface salinity gradients and wind‐induced differential advection. Since this is a generic mechanism, such salinity inversions can likely constitute a typical feature of the upper ocean in regions with distinct thermoclines and shallow mixed layers. Plain Language Summary: The upper ocean is characterized by a well‐mixed surface layer, below which temperature decreases rapidly with depth, forming the so‐called thermocline region. A corresponding salinity increase with depth is typically anticipated for stable density stratification to occur. Temperature and salinity inversions can, however, emerge in the upper ocean. Such thermohaline inversions have been observed in different regions of the world's oceans, and various mechanisms have been proposed to explain their generation. Here, the central basin of the Baltic Sea is used as a natural laboratory to explore the formation of distinct salinity minima in the thermocline region during summer conditions. Using high‐resolution numerical simulations and measurements from a field campaign, we show that inversions are abundant and can emerge throughout the entire basin. They increase with increasing wind speeds and concentrate mainly in regions with strong lateral salinity differences. We propose that thermocline salinity minima can occur during summer when the wind transports saltier water over less saline surface waters. This is a generic mechanism that can therefore be responsible for the formation of the salinity inversions observed worldwide in areas with distinct thermoclines and shallow mixed layers. Key Points: Observations collected in the central Baltic Sea during summer indicate patches of distinct salinity minima in the thermocline regionRealistic high‐resolution simulations are used to explore the origin of the salinity minima and to identify the hotspots of their genesisLateral surface salinity gradients interacting with wind‐induced differential advection are shown to generate most of the inversions [ABSTRACT FROM AUTHOR]

Plain Language Summary: Thank you to the 1,371 reviewers who provided 2,661 reviews during 2021 to ensure the same quality and integrity of JGR‐O manuscripts. Key Point: The editors thank the 2021 peer reviewers [ABSTRACT FROM AUTHOR]

Recently discovered, ocean submesoscales have attracted considerable attention due to their ability to change the upper ocean stratification, affect vertical transport, and induce a downscale cascade of energy toward dissipation. In this paper, we highlight the effect of submesoscale fronts and filaments on surface layer properties and dynamics during storm events, extending previous idealized simulations toward real‐ocean applications. Here, we use the Baltic Sea as a natural laboratory to study the rich submesoscale activity of this system with the help of realistic high‐resolution numerical simulations. These simulations reveal a wealth of cold submesoscale filaments with sharp lateral buoyancy gradients, strong surface convergence, and high vertical velocities. Highly heterogeneous Mixed Layer Depth (MLD) modulations are associated with these features, maintaining locally reduced MLDs even during storm events due to vigorous submesoscale restratification. The interaction of near‐surface turbulence and submesoscale restratification results in strong and highly efficient mixing inside the submesoscale fronts. Focusing on a typical filament, it is shown that frontogenesis is associated with the convergent cross‐front circulation arising from a turbulent thermal wind balance, consistent with previous studies. We show that the sharp fronts generated by this process may become symmetrically unstable, and show enhanced (modeled) energy dissipation rates that are in good quantitative agreement with existing theoretical estimates. Plain Language Summary: Recent studies have revealed that horizontal density differences on scales of 0.1–10 km (submesoscales) are ubiquitous in the surface mixed layer and play an essential role in its evolution. Submesoscale features can restratify, that is, bring warm water above cold water and shallow the depth of the mixed layer, which along with their high vertical velocities, makes them particularly relevant for biology. In this study, we highlight the effect of submesoscales on the restratification process and near‐surface turbulence during the lifetime of storms, thereby extending previous idealized simulations toward real‐ocean applications. We analyze a realistic high‐resolution numerical simulation focusing on the central Baltic Sea, an area where observations from a field campaign confirm that it constitutes a hotspot of submesoscale activity, hence forming an ideal natural laboratory. The simulation reveals a strong lateral temperature gradient that persists during autumn. The basin is found to be rich in submesoscale features that create shallow and heterogeneous Mixed Layer Depths (MLDs). The MLD presents high temporal variability, with the submesoscales being able to maintain shallow MLDs during storms and induce rapid restratification when the wind subsides. Submesoscale restratification tends to counteract the destratification effect caused by atmospheric forcing, yielding stably stratified patches. Key Points: Using realistic simulations a strong surface front, characterized by intense submesoscale activity, was identified in the central Baltic SeaSubmesoscales maintain shallow mixed layers during storms and induce rapid restratification afterward creating stably stratified patchesThe interaction of near‐surface turbulence and submesoscale restratification results in highly efficient mixing inside submesoscale fronts [ABSTRACT FROM AUTHOR]

Intrusions of large amounts of dense and oxygen-rich waters during so-called Major Baltic Inflows (MBIs) form an essential component of the Baltic Sea overturning circulation and deepwater ventilation. Despite their importance, however, detailed observations of the processes occurring in the central basins during an MBI are virtually lacking. Here data from a long-term deployment of an autonomous profiling platform located in the center of one of the main basins are presented, providing the first direct and detailed view of the deepwater modifications and dynamics induced by one of the largest MBIs ever recorded (MBI 2014/2015). Approximately, 21 Gmol of oxygen were imported during three distinct inflow phases with an unexpectedly large contribution of oxic intrusions at intermediate depth. Oxygen consumption rates during the stagnation period immediately following the inflow phase was found to be 87 g m−2 yr−1 with a dominant contribution of sedimentary oxygen demand. The most energetic deepwater processes (topographic and near-inertial waves) were only marginally affected by the inflow; however, subinertial energy levels associated with intrusions and eddies were strongly enhanced. Turbulence microstructure data revealed that the deep interior regions remain essentially nonturbulent even during the energetic conditions of an MBI, emphasizing the importance of boundary mixing. Warm intrusions frequently showed a temperature fine structure with vertical scales of the order of 0.1 m, without any signs of active turbulence. At the upper flanks of these intrusions, double-diffusive staircases were often found to develop, suggesting an important alternative mixing process during inflow conditions. [ABSTRACT FROM AUTHOR]