Impact of the Agulhas Return Current on the oceanography of the Kerguelen Plateau region, Southern Ocean, over the last 40 kyrs
"The oceanography of the western Indian sector of the Southern Ocean is extremely complex due to the presence of several subantartic islands and plateaus that alter the zonal flow of the Antarctic Circumpolar Current. The circulation is even more complex around the Kerguelen Islands (KI) as the hydrological fronts merge with the Agulhas Return Current, the latter transporting warm surface waters from the low latitudes to the Subantarctic Zone (SAZ) east of KI. Here we present new sea-surface and sub-surface temperatures, based on diatom and radiolarian census[...]"
Source: Science Direct
Authors: M.Civel-Mazens et al.
A pole-to-equator ocean ousverturning circulation on Encelad
"Enceladus is believed to have a saltwater global ocean, heated at the ocean–core interface and losing heat to the floating ice shell above. This configuration suggests an important role for vertical convection. The ice shell has dramatic meridional thickness variations that, in steady state, must be sustained by the ocean circulation against processes acting to remove these anomalies. This could be achieved through spatially separated regions of freezing and melting at the ocean–ice interface. Here, we use an idealized[...]"
Source: Nature Geoscience
Authours: Ana H. Lobo et al.
Greenhouse gas cycling by the plastisphere: The sleeper issue of plastic pollution
"Plastic is an allochthonous material to marine ecosystems but is rapidly colonized by marine microbial communities, with an as yet unclear contribution to biogeochemical cycles. In this study, we investigated the influence of an active microbial community grown on microplastic particles (the plastisphere) on CO2 and N2O recycling and its potential role in greenhouse gas inventories and air-sea exchange. Microplastics were collected during two cruises (Cimar 21 and FIP Montes Submarinos) from the surface layer (5 m depth) from several contrasting trophic regions of the South Pacific Ocean, i.e., from a transition zone off the eutrophic coastal upwelling of Chile, to a mesotrophic transition area of oceanic seamounts and, finally, to an oligotrophic zone in the South Pacific Subtropical Gyre. [...]"
Authors: MarcelaCornejo-D’Ottone et al.
Scientists, students to conduct first live, interactive public broadcasts from arctic ocean
The innovative, 18-day Northwest Passage Project research expedition will depart on July 18 from the U.S. Air Base in Thule, Greenland, aboard the Swedish Icebreaker Oden, returning to Thule August 4 after a 2,000 nautical mile voyage through the Northwest Passage [...]"
Dimethylsulfide (DMS) production in polar oceans may be resilient to ocean acidification
"Emissions of dimethylsulfide (DMS) from the polar oceans play a key role in atmospheric processes and climate. Therefore, it is important we increase our understanding of how DMS production in these regions may respond to environmental change. The polar oceans are particularly vulnerable to ocean acidification (OA). However, our understanding of the polar DMS response is limited to two studies conducted in Arctic waters, where in both cases DMS concentrations decreased with increasing acidity. [...]"
Source: Biogeosciences (under Review)
Authors: Frances E. Hopkins et al.
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