Changes of the oceanic CO 2 sink in the Eastern Indian sector of the Southern Ocean

• Published in: Tellus B: Chemical and Physical Meteorology
• Main Authors: Brévière, Emily, Metzl, Nicolas, Poisson, Alain, Tilbrook, Bronte
• 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 2006
• Subjects: [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]; Indian; Southern Ocean
• Online Access: https://hal.science/hal-00770727; https://doi.org/10.1111/J.1600-0889.2006.00220.X

International audience Changes in the carbon dioxide fugacity ( f CO 2 ) and air-sea CO 2 flux observed in the Southern Ocean, south of Tasmania were analysed and compared for two different years: 1996/1997 and 2002/2003. The CO 2 flux showed large and contrasting interannual changes in the permanent open ocean zone (POOZ, 53-61°S) between the 2 yr where the oceanic CO 2 sink increased from about -0.3 mmol m -2 d -1 in February 1997 to -20.6 mmol m -2 d -1 in February 2003. The strong sink in February 2003 was associated with increased phytoplankton biomass in this High-Nutrient, Low-Chlorophyll (HNLC) region. Three hypotheses that may have influenced the biomass and f CO 2 changes in the POOZ were investigated: sea surface temperature (SST) and El Niño/ Southern Oscillation (ENSO) event, total stratospheric ozone column and ultraviolet (UV) radiation, and atmospheric dust inputs. The strong CO 2 sink in 2003 in the POOZ cannot be explained by the observed changes in SST or UV, but would be qualitatively consistent with the presence of episodic atmospheric dust inputs.