More than 30 BIOPOLE scientists, in person or online, took part in the BIOPOLE II cruise planning meeting on 11th Nov at the British Antarctic Survey. The cruise (SD046) will be on board the Sir David Attenborough and will be led jointly by Geraint Tarling and Sophie Fielding of BAS. It will sample large areas of the Scotia and Weddell Sea in the Southern Ocean during February and March, 2025. SD046 is deliberately timed to be in the late summer to autumn period when there is a large seasonal migration of mesozooplankton into deep ocean layers, where they overwinter. It is during this time that many are likely to be washed onto the banks of continental shelves to be predated on by organisms living on the seabed. All of these processes are key to the sequestration of atmospheric carbon into the deep ocean.
During the cruise meeting, Geraint and Sophie firstly outlined the general plan, highlighting the three distinct phases of the cruise (see map above), the first focussing on the South Georgia region (phase SG), the second, a long transect in the eastern Scotia Sea (phase A23) and the third, sampling in the Weddell Sea, particularly the South Orkneys and Powell Basin (phase BP). There will be a different emphasis to the sampling plans in each of these three phases, although all will involve sampling plankton and seabed organisms and measuring the physical and biogeochemical properties of the water.
There followed presentations from each of the science disciplines taking part, including ocean physics, biogeochemistry, phytoplankton, zooplankton, krill, benthic communities, and higher predators/marine mammals. This led into breakout groups considering water sampling protocols, the use of controlled temperature rooms and approaches to higher predator monitoring. The meeting ended with a general discussion on how to prepare for life on board, how activities may differ between sampling stations, and further contingencies in the face of unknown factors such as the early advance of sea-ice over our intended sampling area. These matters, and others, were considered further in the more relaxed atmosphere of the Castle Pub later that evening. In all, a successful meeting and a good foundation on which to develop further plans for the cruise.
The Author of this Article Geraint Tarling (British Antarctic Survey)