Physical controls on the dynamics of phytoplankton biomass, carbon flux and trophic interactions in the North Atlantic during the transition from regimes of winter convection to spring stratification - Cruise No. M87/1 - March 19 - May 02, 2012 - Lisbon (Portugal) - Reykjavik (Iceland)

• Main Authors: Christiansen, Bernd, Backhaus, Jan, Agersted, Mette Dalgard, Basedow, Sünnje, Bellerby, Richard, Blackett, Mike, Bohata, Karolina, Buchholz, Cornelia, Buchholz, Friedrich, Daniels, Chris, Davis, Cabell, De Lange, Tor, Denda, Anneke, Eckardt, André, Esposito, Mario, Giering, Sari, Grenvald, Julie Cornelius, Holste, Linda, Jacob, Katharina Juliane, Jacob, Juliane, Janßen, Silke, Jeansson, Emil, Koppelmann, Rolf, Koski, Marja, Lindemann, Christian, Martin, Bettina, Menden-Deuer, Susanne, Möller, Klas, Morison, Francoise, Naumann, Ann Kristin, Nondal, Gisle, Pankoke, Lene Mausson, Paulsen, Maria Lund, Reichelt, Theresa, Riisgaard, Karen, Silva, Teresa, St. John, Michael, Walter, Bettina
• Format: Report
• Language: English
• Published: DFG-Senatskommission für Ozeanographie 2014
• Subjects: Earth Science; Earth sciences and geology; Norwegian Sea; Calanus finmarchicus; Iceland; North Atlantic
• Online Access: https://dx.doi.org/10.2312/cr_m87_1; https://www.tib.eu/suchen/id/awi:5555564e9f18b771f14f8233b3568baf7ec22715

Recent studies suggest that winter convection contributes to a high biomass of phytoplankton in the deep convective layer, which is in contradiction to the classical spring bloom critical depth model of phytoplankton bloom dynamics. In order to investigate the implications of these two regimes for biogeochemical fluxes and ecosystem dynamics, cruise M87/1 as part of the EU project EURO-BASIN aimed to study the mechanisms influencing winter phytoplankton production and biomass, to resolve the fate of phytoplankton biomass produced during the winter convective period (i.e. flux to depth), and to examine its impact on exit from diapause of Calanus finmarchicus, a key secondary producer in this system. The cruise involved repeated physical (water masses, flowfield), chemical (nutrients), geochemical (carbonate system) and biological (phytoplankton, zooplankton, micronekton) sampling and focused on three main study sites in the North Atlantic. The first station was located in the Iceland Basin to the south of the Iceland-Faroe Ridge and was sampled four times during the cruise. The second station in the southern part of the Norwegian Sea was sampled three times, and the third station in the northern North Sea twice. The full sampling programme was performed at these locations, involving a variety of different gears like CTDrosette, different plankton nets, pumps, video plankton recorder, laser-optical plankton counter, marine snow catcher. Additional stations with a reduced sampling programme were located in the Norwegian Sea, in the Faroe-Scotland Channel and to the north and west of the Shetlands. : METEOR-Berichte