Russian Journal of Earth Sciences Russian Journal of Earth Sciences Russian Journal of Earth Sciences 1681-1208 46596 10.2205/2019ES000679 ОРИГИНАЛЬНЫЕ СТАТЬИ ORIGINAL ARTICLES ОРИГИНАЛЬНЫЕ СТАТЬИ Thermohaline structure of Antarctic Bottom Water in the abyssal basins of the South Atlantic Thermohaline structure of Antarctic Bottom Water in the abyssal basins of the South Atlantic Frey D I Frey D I Morozov E G Morozov E G egmorozov@mail.ru Ansorge I Ansorge I Fomin V V Fomin V V Diansky N A Diansky N A Tarakanov R Yu Tarakanov R Yu Shirshov Institute of Oceanology RAS ru Shirshov Institute of Oceanology RAS ru Shirshov Institute of Oceanology RAS ru Shirshov Institute of Oceanology RAS ru University of Cape Town, Rondebosch ru University of Cape Town, Rondebosch ru Zubov State Oceanographic Institute ru Zubov State Oceanographic Institute ru Zubov State Oceanographic Institute; Lomonosov Moscow State University; Institute of Numerical Mathematics RAS ru Zubov State Oceanographic Institute; Lomonosov Moscow State University; Institute of Numerical Mathematics RAS ru Shirshov Institute of Oceanology RAS ru Shirshov Institute of Oceanology RAS ru 19 5 29 10 2021 https://ras.editorum.ru/en/nauka/article/46596/view

Antarctic Bottom Water (AABW) occupies the lowest ocean layer in the major part of the Atlantic. Despite the fact that this water has the same origin from the Weddell Sea, thermohaline properties of bottom layers vary strongly in different deep basins. Temperature and salinity increase along the pathways of bottom water propagation is caused by mixing of AABW with the warmer and more saline water in the overlying layers. This mixing strongly intensifies over underwater ridges; in addition, these ridges determine the pathways of bottom water spreading. Thus, the ocean topography plays the most important role in the formation of thermohaline structure of deep basins. In particular, the properties of AABW in the western and eastern parts of the South Atlantic significantly differ from each other. In this paper we compare temperature and salinity structure of the abyssal waters of the Southeast and Southwest Atlantic. We used the results of high spatial resolution modeling and hydrographic measurements for this study. We also simulated the velocity field in the bottom layer of the South Atlantic.

Antarctic Bottom Water (AABW) occupies the lowest ocean layer in the major part of the Atlantic. Despite the fact that this water has the same origin from the Weddell Sea, thermohaline properties of bottom layers vary strongly in different deep basins. Temperature and salinity increase along the pathways of bottom water propagation is caused by mixing of AABW with the warmer and more saline water in the overlying layers. This mixing strongly intensifies over underwater ridges; in addition, these ridges determine the pathways of bottom water spreading. Thus, the ocean topography plays the most important role in the formation of thermohaline structure of deep basins. In particular, the properties of AABW in the western and eastern parts of the South Atlantic significantly differ from each other. In this paper we compare temperature and salinity structure of the abyssal waters of the Southeast and Southwest Atlantic. We used the results of high spatial resolution modeling and hydrographic measurements for this study. We also simulated the velocity field in the bottom layer of the South Atlantic.

 Antarctic Bottom Water deep-water processes thermohaline structure numerical modeling Antarctic Bottom Water deep-water processes thermohaline structure numerical modeling The work was carried out within the State Task of the Russian Federation 0128-2019-0009; the research was supported by the Russian Foundation for Basic Research (grant 19-57-60001, numerical simulations, and 19-05-00878, model adjustment) and by the Russian Science Foundation (grant 16-17-10149, data analysis). The work of I. Ansorge was supported by the National Research Foundation of South Africa (Grant UID 118901).

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