Russian Journal of Earth Sciences Russian Journal of Earth Sciences Russian Journal of Earth Sciences 1681-1208 89566 10.2205/2024ES000948 gjrpbt ОРИГИНАЛЬНЫЕ СТАТЬИ ORIGINAL ARTICLES ОРИГИНАЛЬНЫЕ СТАТЬИ Distribution of Dissolved Oxygen and Nutrients in Abyssal Waters Flowing into the Brazil Basin, Southwest Atlantic Distribution of Dissolved Oxygen and Nutrients in Abyssal Waters Flowing into the Brazil Basin, Southwest Atlantic https://orcid.org/0009-0006-1489-8933 Селиверстова Анна М Seliverstova Anna M https://orcid.org/0000-0001-6856-4783 Зуев Олег Александрович Zuev Oleg Aleksandrovich qillous@gmail.com https://orcid.org/0000-0001-8141-9513 Фрей Дмитрий Ильич Frey D. I. https://orcid.org/0000-0001-6440-060X Кречик Виктор А. Krechik Viktor A https://orcid.org/0000-0002-0251-3454 Морозов Евгений Георгиевич Morozov Eugene Georgievich egmorozov@mail.ru Институт океанологии им. П.П. Ширшова РАН Россия Shirshov Institute of Oceanology RAS Russian Federation Институт океанологии им. П.П. Ширшова РАН P.P.Shirshov Institute of Oceanology of the Russian Academy of Science Институт океанологии им. П.П. Ширшова РАН Россия Shirshov Institute of Oceanology RAS Russian Federation Институт океанологии им. П.П. Ширшова РАН Россия Shirshov Institute of Oceanology RAS Russian Federation Институт океанологии им. П.П. Ширшова РАН Россия Shirshov Institute of Oceanology RAS Russian Federation 30 12 2024 30 12 2024 24 6 1 11 10 10 2024 05 11 2024 https://rjes.ru/en/nauka/article/89566/view

The Vema Channel is a deep narrow passage in the South Atlantic and a main path for bottom water which flows northward from the Argentine Basin to the Brazil Basin and after all into the North Atlantic. The thermohaline structure and dynamics in it have been studied for many years. In this study we report our new data on dissolved oxygen and nutrients measurements performed in 2022 at the exit of the Vema Channel. This is the first time that such measurements have been made with high spatial resolution. Data from standard oceanographic sections located near the study area are also analyzed. A significant dependence in the distribution of dissolved oxygen and nutrients on the hydrological structure is shown. Local dissolved oxygen minimum indicates the lower boundary of Circumpolar waters. It was also revealed insignificant temporal variability of nutrients concentration.

The Vema Channel is a deep narrow passage in the South Atlantic and a main path for bottom water which flows northward from the Argentine Basin to the Brazil Basin and after all into the North Atlantic. The thermohaline structure and dynamics in it have been studied for many years. In this study we report our new data on dissolved oxygen and nutrients measurements performed in 2022 at the exit of the Vema Channel. This is the first time that such measurements have been made with high spatial resolution. Data from standard oceanographic sections located near the study area are also analyzed. A significant dependence in the distribution of dissolved oxygen and nutrients on the hydrological structure is shown. Local dissolved oxygen minimum indicates the lower boundary of Circumpolar waters. It was also revealed insignificant temporal variability of nutrients concentration.

 Vema Channel abyssal waters dissolved oxygen silicate phosphate nitrate Vema Channel abyssal waters dissolved oxygen silicate phosphate nitrate This work was supported by the Russian Science Foundation grant 24-27-00181. This work was supported by the Russian Science Foundation grant 24-27-00181.

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