The oceans play an important role in mitigating climate change by acting as large carbon sinks, especially at high latitude regions. The Southern Ocean plays a major role in the global carbon dioxide (CO2) budget. This work aims to investigate the behavior of turbulent CO2 fluxes and quantify it under different atmospheric and oceanic conditions in the Drake Passage and Bransfield Strait regions on high spatiotemporal resolutions when compared with traditional CO2 fluxes estimations. The atmospheric stability condition was used to corroborate the description of CO2 fluxes. In situ, satellite, and reanalysis data from 08 to 22 November 2018, were used in this work. The Bransfield Strait uptaked 38.59% more CO2 than the Drake Passage due to the cold and fresh waters, allied to the influence of glacial meltwater dilution. Which increased the CO2 solubility, directing the CO2 fluxes to the ocean. The Bransfield Strait had predominantly stable atmospheric conditions, which contributed to this region acting as a CO2 sink. The Drake Passage, on average, behaved as a CO2 sink, mainly due to physical characteristics. This research contributes to a better understanding of the Southern Ocean’s role in the global carbon balance on scales that are very difficult to monitor.
1 January 2022 in Anais da Academia Brasileira de Ciências
The Antarctic region has experienced recent climate and environmental variations due to climate change, such as ice sheets and ice shelves loss, and changes in the production, extension, and thickness of sea-ice. These processes mainly affect the freshwater supply to the Southern Ocean and its water masses formation and export, being crucial to changes in the global climate. Here, we review the influence of the glacial freshwater input on the Antarctic Peninsula adjacent ocean. We highlight each climate process' relevance on freshwater contribution to the sea and present a current overview of how these processes are being addressed and studied. The increase of freshwater input into the ocean carries several implications on climate, regionally and globally. Due to glacier melting, the intrusion of colder and lighter water into the ocean increases the stratification of the water column, influencing the sea-ice increase and reducing ocean-atmosphere exchanges, affecting the global water cycle. This study shows the role of each hydrological cycle processes and their contributions to the regional oceanography and potentially to climate.
Oceanic mesoscale activity influences the atmosphere in the southwestern and southern sectors of the Atlantic Ocean. However, the influence of high latitudes, specifically sea ice, on mid-latitudes and a better understanding of mesoscale ocean–atmosphere thermodynamic interactions still require further study. To quantify the effects of oceanic mesoscale activity during the periods of maximum and minimum Antarctic sea ice extent (September 2019 and February 2020), numerical experiments were conducted using a coupled regional model and an online two-dimensional spatial filter to remove high-frequency sea surface temperature (SST) oscillations. The largest SST anomalies were observed in the Brazil–Malvinas Confluence and along oceanic fronts in September, with maximum SST anomalies reaching 4.23 °C and −3.71 °C. In February, the anomalies were 2.18 °C and −3.06 °C. The influence of oceanic mesoscale activity was evident in surface atmospheric variables, with larger anomalies also observed in September. This influence led to changes in the vertical structure of the atmosphere, affecting the development of the marine atmospheric boundary layer (MABL) and influencing the free atmosphere above the MABL. Modulations in precipitation patterns were observed, not only in oceanic regions, but also in adjacent continental areas. This research provides a novel perspective on ocean–atmosphere thermodynamic coupling, highlighting the mesoscale role and importance of its representation in the study region.
19 June 2023 in Quarterly Journal of the Royal Meteorological Society