Dissolved inorganic carbon budgets in the eastern subpolar North Atlantic in the 2000s from in situ data

• Published in: Geophysical Research Letters
• Main Authors: Zunino, Patricia, Lherminier, Pascale, Mercier, Herle, Padin, Xose A., Rios, Aida F., Perez, Fiz F.
• Other Authors: Laboratoire d'Océanographie Physique et Spatiale (LOPS), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique des océans (LPO), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS), European Project: 264879,EC:FP7:ENV,FP7-ENV-2010,CARBOCHANGE(2011)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2015
• Subjects: [SDU]Sciences of the Universe [physics]; North Atlantic
• Online Access: https://hal.science/hal-04200774; https://hal.science/hal-04200774/document; https://hal.science/hal-04200774/file/Geophysical%20Research%20Letters%20-%202015%20-%20Zunino%20-%20Dissolved%20inorganic%20carbon%20budgets%20in%20the%20eastern%20subpolar%20North%20Atlantic%20in.pdf; https://doi.org/10.1002/2015GL066243

International audience The subpolar North Atlantic (SPNA) is important in the global carbon cycle because of the deep water ventilation processes that lead to both high uptake of atmospheric CO2 and large inventories of anthropogenic CO2 (C-ant). Thus, it is crucial to understand its response to increasing anthropogenic pressures. In this work, the budgets of dissolved inorganic carbon (DIC), C-ant and natural DIC (DICnat) in the eastern SPNA in the 2000s, are jointly analyzed using in situ data. The DICnat budget is found to be in steady state, confirming a long-standing hypothesis from in situ data for the first time. The biological activity is driving the uptake of natural CO2 from the atmosphere. The C-ant increase in the ocean is solely responsible of the DIC storage rate which is explained by advection of C-ant from the subtropics (65%) and C-ant air-sea flux (35%). These results demonstrate that the C-ant is accumulating in the SPNA without affecting the natural carbon cycle.