About this Research Topic
The Southern Ocean is a critical component of the Earth's climate system, playing a crucial role in global oceanic circulation and climate regulation. Its dynamics facilitate the exchange of water masses, heat, freshwater, dissolved gases, and nutrients between the Southern Ocean and lower latitudes.
In the last decades, the Southern Ocean has undergone significant changes due to variations in atmospheric forcing, air-sea heat and freshwater exchange. North of 60°S, local warming, salinity increase, zonal acceleration of the ACC fronts and deepened isopycnals have been observed, while salinity has notably decreased south of 70°S. Several pieces of evidence support that the freshening of the Antarctic coastal region has strengthened the Antarctic Coastal Current and weakened the lower limb of the abyssal overturning circulation, reducing the deep ocean oxygen content. This slowdown is also attributed to the reduction in dense-water production, especially in the Weddell Sea, influenced by the declining sea-ice formation and northerly wind trends. These changes have critical implications for global ocean circulation and climate, such as a reduction in the Earth's surface albedo, a decrease in the ocean's capacity to absorb CO2, a global sea-level rise and AMOC alterations.
Despite its global consequences, the Southern Ocean remains one of the least understood and most challenging regions to study. Fortunately, technological advancements have revolutionized its assessment, providing new opportunities to observe and understand its complex dynamics. Integrating advanced observational techniques such as machine learning (ML), artificial intelligence (AI), and sophisticated regional or global numerical models (such as NEMO, MITgcm, etc.) is essential for capturing the processes at play and predicting eventual future changes.
This Research Topic aims to bring together cutting-edge research that enhances our understanding of the physical oceanography of the Southern Ocean, focusing on its dynamics, interactions with the atmosphere, and response to climate change. We invite contributions that address any of the subtopics mentioned below:
1. Ocean Circulation:
◦ Antarctic Circumpolar Current (ACC): Research on the structure, spatiotemporal variability and trends, ventilation, eddy kinetic energy, topographic interactions, upwelling and nutrient interbasin distribution, barotropic dynamics of the ACC, importance of the cold-water route and its role in global ocean circulation.
◦ Deep Water and Water Mass Formation: Studies on the deep-water formation, distribution, deep convection, water mass transformation and transport of mode and intermediate waters and their influence on the global thermohaline circulation.
2. Atmosphere-Ocean Interactions:
◦ Antarctic Oscillation (AAO)/Southern Annular Mode (SAM) and ENSO: Impacts of these climatic phenomena on the dynamics of the Southern Ocean, including changes in temperature, salinity, stratification, ventilation, and wind stress patterns in a large or regional scale. Moreover, seasonal and long-term interactions and correlations in SAM/ENSO phases and ACC strength.
◦ Heat and Moisture Exchange: Studies on heat and moisture exchange processes between the atmosphere and the ocean, meridional and vertical fluxes and their influence on regional and global climate, especially in terms of sea ice formation and marine productivity.
3. Effects of Climate Change:
◦ Warming Trends: Research on how climate change is affecting the sea surface temperature of the Southern Ocean, the mixed layer depth, implications for ocean dynamics, heat sink, warmer water intrusions towards the ice shelves, impacts of the sea ice decline and tipping points.
◦ Climate Feedbacks: Studies on positive and negative feedbacks (e.g. surface albedo, heat uptake, sea ice loss, etc.) and driver mechanisms between the Southern Ocean and the global climate system.
4. Sea Ice, Icebergs and Ice Shelves Dynamics:
◦ Ice-Ocean Interaction: Studies on how changes in sea ice extent and formation in coastal polynyas affect brine rejection, thermohaline circulation, mixing, dense water formation, ice-shelf stability and heat exchanges.
◦ Icebergs Calving and Melting: Research on trends in iceberg calving rates, iceberg drifts and ocean circulation, exploring interactions between icebergs and sea ice, and their contribution of freshwater to various ocean basins.
◦ Glacier and Ice Shelf Melting: Impact of glacier and ice shelf melting (basal melting, runoff, subglacial runoff, etc.) on water column stratification and ocean dynamics.
5. Mixing and Stratification Processes:
◦ Turbulence and Vertical Mixing: Research on vertical mixing processes and turbulent energy dissipation rates, and their impact on ocean stratification and nutrient distribution.
◦ Stratification and Circulation: Studies on how isopycnal, eddy-induced and wind-driven mixing affect the stratification and its subsequent influence on circulation and water mass dynamics in the Southern Ocean.
6. Technological Innovations in Physical Oceanography:
◦ Observation and Monitoring: Development and application of new technologies and methodologies for observing and monitoring physical dynamics in the Southern Ocean, including the use of satellites, floats, moorings and autonomous underwater vehicles.
◦ Machine Learning and Artificial Intelligence: Applications of ML and AI for analyzing oceanographic data, enhancing predictive models, and improving real-time monitoring systems.
◦ Modeling and Simulation: Advances in coupled and high-resolution regional numerical models and long-term simulations to predict changes in Southern Ocean dynamics under different climate scenarios.
We invite researchers to submit original articles addressing any of the abovementioned topics. The goal is to advance the understanding of the physical oceanography of the Southern Ocean and its importance in the global climate system.
In the last decades, the Southern Ocean has undergone significant changes due to variations in atmospheric forcing, air-sea heat and freshwater exchange. North of 60°S, local warming, salinity increase, zonal acceleration of the ACC fronts and deepened isopycnals have been observed, while salinity has notably decreased south of 70°S. Several pieces of evidence support that the freshening of the Antarctic coastal region has strengthened the Antarctic Coastal Current and weakened the lower limb of the abyssal overturning circulation, reducing the deep ocean oxygen content. This slowdown is also attributed to the reduction in dense-water production, especially in the Weddell Sea, influenced by the declining sea-ice formation and northerly wind trends. These changes have critical implications for global ocean circulation and climate, such as a reduction in the Earth's surface albedo, a decrease in the ocean's capacity to absorb CO2, a global sea-level rise and AMOC alterations.
Despite its global consequences, the Southern Ocean remains one of the least understood and most challenging regions to study. Fortunately, technological advancements have revolutionized its assessment, providing new opportunities to observe and understand its complex dynamics. Integrating advanced observational techniques such as machine learning (ML), artificial intelligence (AI), and sophisticated regional or global numerical models (such as NEMO, MITgcm, etc.) is essential for capturing the processes at play and predicting eventual future changes.
This Research Topic aims to bring together cutting-edge research that enhances our understanding of the physical oceanography of the Southern Ocean, focusing on its dynamics, interactions with the atmosphere, and response to climate change. We invite contributions that address any of the subtopics mentioned below:
1. Ocean Circulation:
◦ Antarctic Circumpolar Current (ACC): Research on the structure, spatiotemporal variability and trends, ventilation, eddy kinetic energy, topographic interactions, upwelling and nutrient interbasin distribution, barotropic dynamics of the ACC, importance of the cold-water route and its role in global ocean circulation.
◦ Deep Water and Water Mass Formation: Studies on the deep-water formation, distribution, deep convection, water mass transformation and transport of mode and intermediate waters and their influence on the global thermohaline circulation.
2. Atmosphere-Ocean Interactions:
◦ Antarctic Oscillation (AAO)/Southern Annular Mode (SAM) and ENSO: Impacts of these climatic phenomena on the dynamics of the Southern Ocean, including changes in temperature, salinity, stratification, ventilation, and wind stress patterns in a large or regional scale. Moreover, seasonal and long-term interactions and correlations in SAM/ENSO phases and ACC strength.
◦ Heat and Moisture Exchange: Studies on heat and moisture exchange processes between the atmosphere and the ocean, meridional and vertical fluxes and their influence on regional and global climate, especially in terms of sea ice formation and marine productivity.
3. Effects of Climate Change:
◦ Warming Trends: Research on how climate change is affecting the sea surface temperature of the Southern Ocean, the mixed layer depth, implications for ocean dynamics, heat sink, warmer water intrusions towards the ice shelves, impacts of the sea ice decline and tipping points.
◦ Climate Feedbacks: Studies on positive and negative feedbacks (e.g. surface albedo, heat uptake, sea ice loss, etc.) and driver mechanisms between the Southern Ocean and the global climate system.
4. Sea Ice, Icebergs and Ice Shelves Dynamics:
◦ Ice-Ocean Interaction: Studies on how changes in sea ice extent and formation in coastal polynyas affect brine rejection, thermohaline circulation, mixing, dense water formation, ice-shelf stability and heat exchanges.
◦ Icebergs Calving and Melting: Research on trends in iceberg calving rates, iceberg drifts and ocean circulation, exploring interactions between icebergs and sea ice, and their contribution of freshwater to various ocean basins.
◦ Glacier and Ice Shelf Melting: Impact of glacier and ice shelf melting (basal melting, runoff, subglacial runoff, etc.) on water column stratification and ocean dynamics.
5. Mixing and Stratification Processes:
◦ Turbulence and Vertical Mixing: Research on vertical mixing processes and turbulent energy dissipation rates, and their impact on ocean stratification and nutrient distribution.
◦ Stratification and Circulation: Studies on how isopycnal, eddy-induced and wind-driven mixing affect the stratification and its subsequent influence on circulation and water mass dynamics in the Southern Ocean.
6. Technological Innovations in Physical Oceanography:
◦ Observation and Monitoring: Development and application of new technologies and methodologies for observing and monitoring physical dynamics in the Southern Ocean, including the use of satellites, floats, moorings and autonomous underwater vehicles.
◦ Machine Learning and Artificial Intelligence: Applications of ML and AI for analyzing oceanographic data, enhancing predictive models, and improving real-time monitoring systems.
◦ Modeling and Simulation: Advances in coupled and high-resolution regional numerical models and long-term simulations to predict changes in Southern Ocean dynamics under different climate scenarios.
We invite researchers to submit original articles addressing any of the abovementioned topics. The goal is to advance the understanding of the physical oceanography of the Southern Ocean and its importance in the global climate system.
Keywords: Southern Ocean, Physical processes, Ocean dynamics, Climate change, Ocean interactions
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.
