FN Archimer Export Format PT J TI Assessing net primary production in the northwestern Barents Sea using in situ, remote sensing and modelling approaches BT AF Castro de la Guardia, Laura HERNANDEZ FARINAS, Tania Marchese, Christian Amargant-Arumí, Martí Myers, Paul G. Bélanger, Simon Assmy, Philipp Gradinger, Rolf Duarte, Pedro AS 1:1;2:2;3:3,4;4:5;5:6;6:7;7:1;8:5;9:1; FF 1:;2:PDG-ODE-LITTORAL-LERN;3:;4:;5:;6:;7:;8:;9:; C1 Norwegian Polar Institute, Fram Centre, Tromsø, Norway Ifremer, Normandy, France University of British Columbia, British Columbia, Canada University of Victoria, British Columbia, Canada UiT, The Arctic University of Norway, Tromsø, Norway University of Alberta, Edmonton, Alberta, Canada Université Québec à Rimouski, Quebec, Canada C2 NORWEGIAN POLAR INST, NORWAY IFREMER, FRANCE UNIV BRITISH COLUMBIA, CANADA UNIV VICTORIA, CANADA UNIV ARCTIC UIT NORWAY, NORWAY UNIV ALBERTA, CANADA UNIV QUEBEC (UQAR), CANADA SI PORT-EN-BESSIN SE PDG-ODE-LITTORAL-LERN IN WOS Ifremer UPR copubli-europe copubli-int-hors-europe IF 4.1 TC 1 UR https://archimer.ifremer.fr/doc/00861/97310/106302.pdf https://archimer.ifremer.fr/doc/00861/97310/106303.pdf LA English DT Article DE ;Net primary production;Northwestern Barents Sea;Bioregionalization;Nansen Legacy AB The northwestern Barents Sea (NW-BS) is a highly productive region within the transitional zones of an Atlantic to Arctic-dominated marine ecosystem. The steep latitudinal gradients in sea ice concentration, Atlantic and Arctic Water, offer an opportunity to test hypotheses on physical drivers of spatial and temporal variability of net primary production (NPP). However, quantifying NPP in such a large ocean region can be challenging by the lack of in situ measurements with high spatial and temporal resolution, and gaps in remote sensing estimates due to the presence of clouds and sea ice, and assumptions regarding the depth distribution of biomass. Without reliable data to evaluate models, filling these gaps with numerical models is limited by the model representation of the physical environment and its assumptions about the relationships between NPP and its main limiting factors. Hence, within the framework of the Nansen Legacy Project, we combined in situ measurements, remote sensing, and model simulations to constrain the estimates of phytoplankton NPP in NW-BS. The region was subdivided into Atlantic, Subarctic, and Arctic subregions on the basis of different phytoplankton phenology. In 2004 there was a significant regime change in the Atlantic subregion that resulted in a step-increase in NPP in tandem with a step-decrease in sea ice concentration. However, neither region experienced significant long term trends in NPP despite changes in the physical environment. Mixing was the main driver of simulated annual NPP in the Atlantic subregion, while light and nutrients drove annual NPP in the Subarctic and Arctic subregions. The multi-source estimate of annual NPP ranged 79–118 gC m−2 yr−1 in the Atlantic, 74–82 gC m−2 yr−1 in the Subarctic, and 19–47 gC m−2 yr−1 in the Arctic. The total NPP in the NW-BS region was estimated between 15 and 48 Tg C yr−1, which is 15–50% of the total NPP needed to sustain three of the most harvested fish species north of 62°N (roughly  90 Tg C yr−1). This research shows the importance of continuing to strive for better regional estimates of NPP. PY 2023 PD DEC SO Progress In Oceanography SN 0079-6611 PU Elsevier BV VL 219 UT 001125248400001 DI 10.1016/j.pocean.2023.103160 ID 97310 ER EF