Mesoscale and diel to monthly variability of CO 2 and carbon fluxes at the ocean surface in the northeastern Atlantic

• Published in: Journal of Geophysical Research
• Main Authors: Merlivat, Liliane, González-Dávila, Melchor, Caniaux, Guy, Boutin, Jacqueline, Reverdin, Gilles
• Other Authors: Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), 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)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-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)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Facultad de Ciencias del Mar (FCM), University of Las Palmas de Gran Canaria (ULPGC)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2009
• Subjects: Oceanography: Biological and Chemical: Biogeochemical cycles processes and modeling (0412 0414 0793 1615 4912); Biogeosciences: Diel seasonal and annual cycles (4227); Oceanography: Biological and Chemical: Carbon cycling (0428); Biogeosciences: Carbon cycling (4806); Oceanography: General: Physical and biogeochemical interactions; [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph]; [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph]; Northeast Atlantic
• Online Access: https://hal.science/hal-00760286; https://hal.science/hal-00760286/document; https://hal.science/hal-00760286/file/2007JC004657.pdf; https://doi.org/10.1029/2007JC004657

International audience Four CARIOCA Lagrangian buoys were deployed in the northeast Atlantic Ocean as part of the Programme Océan Multidisciplinaire Méso Echelle (POMME) dedicated to the study of the role of mesoscale eddies in biological production, the carbon budget, and the subduction of mode waters. An extensive set of hourly surface measurements of temperature, salinity, and carbon dioxide fugacity ( f CO 2 ) was collected from February to August 2001. The high-frequency spatial and temporal variability observed in surface f CO 2 and in the derived dissolved inorganic carbon (DIC) concentrations suggests that abrupt changes of the carbon variables are being generated along frontal patterns and filaments by submesoscale and mesoscale eddy-eddy interactions, especially in winter. On the basis of a 1-D model of the diurnal mixed layer along the buoy trajectory, we show that under certain conditions the diel cycle of DIC is driven by the daily cycle of photosynthesis and metabolic CO 2 release at the ocean surface. This information is quantitatively used to derive in-situ primary production, carbon gross, and net community production. The analysis of 107 observed diel cycles of DIC shows that episodic biological production processes are triggered by the mesoscale activity of surface eddies. Over the sampled period, the POMME area is a sink for atmospheric CO 2 with an estimated flux of -4 mmol m -2 day -1 . The calculated amount of anthropogenic carbon transported into the ocean interior by subduction of subpolar mode water is equal to 2.8 10 13 gC yr -1 .