Submeso-scale Mixing Features in the Gerlache Strait Bays (Antarctica)
DOI:
https://doi.org/10.25268/bimc.invemar.2021.50.SuplEsp.934Keywords:
Sea ice, Antarctic Ocean dynamics, Diapycnal mixing, Gerlache Strait, Mixing.Abstract
Measurements of turbulence in the ocean are sparse, especially in environments such as Antarctica. Here we map the spatial distribution of diapycnal diffusivities and the water column characteristics across the three main bays in the Gerlache Strait on the western side of the Antarctic Peninsula. The measurements were recorded during the Fifth Colombian Antarctic Expedition, 2018-2019, using a Vertical Microstructure Profiler in free fall for the first 400 m, to record fluctuations of vertical shear at dissipation scales (10-3 – 103 m). Diapycnal diffusivities are higher by 1-2 orders of magnitude in the Gerlache mainstream compared with the interior bays, with values from O ( ) to O ( ) respectively over the upper 400 m. The highest mixing values were recorded in the southern section compared to the northern one, indicating better well-mixed water in the south. Observed hot spots of higher turbulence levels may be associated with the interaction of the entrance of the Upper Circumpolar Depth Water, the Antarctic Surface Water, and Weddell Sea Deep Waters with resident waters and topography.
Author Biographies
Jhon Fredy Mojica Moncada, Center for global Sea Level Change (CSLC), New York University Abu Dhabi (NYUAD)
Research Associate
Center for global Sea Level Change
NYU Abu Dhabi
David Holland, Center for global Sea Level Change (CSLC), New York University Abu Dhabi (NYUAD)
Julio cesar Monroy, Decano Facultad de Oceanografía Física Escuela Naval de Cadetes "Almirante Padilla"
Capitán de Corbeta JULIO CÉSAR MONROY SILVERA
Decano Facultad de Oceanografía Física
Escuela Naval de Cadetes "Almirante Padilla"
Barrio Bosque, sector Isla Manzanillo
Celular: (+57) 313 2109417
Cartagena, Colombia
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