Trends in North Atlantic sea-surface f CO 2 from 1990 to 2006

• Published in: Deep Sea Research Part II: Topical Studies in Oceanography
• Main Authors: Schuster, Ute, Watson, Andrew J., Bates, Nicholas R., Corbière, Antoine, Gonzalez-Davila, M., Metzl, Nicolas, Pierrot, Denis, Santana-Casiano, M.
• Other Authors: Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Institut Pierre-Simon-Laplace (IPSL), École normale supérieure - Paris (ENS-PSL), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X), Institut Polytechnique de Paris (IP Paris)-Institut Polytechnique de Paris (IP Paris)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Institut Polytechnique de Paris (IP Paris)-Institut Polytechnique de Paris (IP Paris)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: CCSD 2009
• Subjects: Carbon dioxide; Sea surface; North Atlantic; Temporal variations; Sea–air flux of CO 2; [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph]; [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph]; [SDE.MCG]Environmental Sciences/Global Changes; North Atlantic oscillation
• Online Access: https://hal.science/hal-00763146; https://doi.org/10.1016/J.DSR2.2008.12.011

International audience We examine observations from 1990 to 2006 from four voluntary observing ships and two time-series stations in the North Atlantic, fitting a sinusoidal annual cycle and linear year-on-year trend at all locations where there are sufficient data. Results show that in the subtropical regions, sea-surface f CO 2 has closely followed the increasing trend in atmospheric f CO 2 . In contrast, farther north, sea-surface f CO 2 has increased faster than f CO 2 in the atmosphere. The resulting Δ f CO 2 , driving air–sea flux of CO 2 , has therefore decreased in the North Atlantic, particularly at higher latitudes, as has the annual mean air–sea flux. Several underlying causes may have led to the observed changes in sea-surface f CO 2 . Low-frequency modes, such as the North Atlantic Oscillation, lead to changes in the sea-surface temperature, in sea-surface circulation and in vertical mixing, affecting sea-surface f CO 2 through biogeochemical processes. A comparison with measurements covering a longer time period shows that the sea-surface f CO 2 rise has accelerated since 1990 in the northern North Atlantic.