Multiple constraints on regional CO2 flux variations over land and oceans

• Published in: Global Biogeochemical Cycles
• Main Authors: Peylin, Philippe, Bousquet, P., Le Quéré, C., Sitch, S., Friedlingstein, P., Mckinley, G., Gruber, N., Rayner, P., Ciais, P.
• Other Authors: Biogéochimie et écologie des milieux continentaux (Bioemco), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Recherche Agronomique (INRA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE), 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-Saclay-Centre National de la Recherche Scientifique (CNRS), Modélisation INVerse pour les mesures atmosphériques et SATellitaires (SATINV), 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-Saclay-Centre National de la Recherche Scientifique (CNRS)-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-Saclay-Centre National de la Recherche Scientifique (CNRS), ICOS-ATC (ICOS-ATC)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2005
• Subjects: TERRESTRIAL ECOSYSTEMS; NORTH-ATLANTIC OCEAN; ATMOSPHERIC CARBON-DIOXIDE; INTERANNUAL CLIMATE VARIABILITY; EL-NINO; SUBTROPICAL ECOSYSTEMS; SOUTHERN OSCILLATION; VEGETATION DYNAMICS; CIRCULATION MODEL; DECIDUOUS FOREST; [SDE.MCG]Environmental Sciences/Global Changes; [SDU]Sciences of the Universe [physics]; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; Austral; Austral Ocean; Pacific; North Atlantic
• Online Access: https://hal-bioemco.ccsd.cnrs.fr/bioemco-00175981; https://hal-bioemco.ccsd.cnrs.fr/bioemco-00175981/document; https://hal-bioemco.ccsd.cnrs.fr/bioemco-00175981/file/2003GB002214.pdf; https://doi.org/10.1029/2003GB002214

International audience To increase our understanding of the carbon cycle, we compare regional estimates of CO2 flux variability for 1980 - 1998 from atmospheric CO2 inversions and from process-based models of the land (SLAVE and LPJ) and ocean (OPA and MIT). Over the land, the phase and amplitude of the different estimates agree well, especially at continental scale. Flux variations are predominantly controlled by El Nino events, with the exception of the post-Pinatubo period of the early 1990s. Differences between the two land models result mainly from the response of heterotrophic respiration to precipitation and temperature. The "Lloyd and Taylor'' formulation of LPJ [Lloyd and Taylor, 1994] agrees better with the inverse estimates. Over the ocean, inversion and model results agree only in the equatorial Pacific and partly in the austral ocean. In the austral ocean, an increased CO2 sink is present in the inversion and OPA model, and results from increased stratification of the ocean. In the northern oceans, the inversions estimate large flux variations in line with time-series observations of the subtropical Atlantic, but not supported by the two model estimates, thus suggesting that the CO2 variability from high-latitude oceans needs further investigation.