Data-based estimates of the ocean carbon sink variability – first results of the Surface Ocean pCO2 Mapping intercomparison (SOCOM)

Type Article
Date 2015-08-27
Language English
Author(s) Rödenbeck C.1, Bakker D. C. E.2, Gruber N.3, Iida Y.4, Jacobson A. R.5, 16, Jones S.13, Landschützer P.3, Metzl N.6, Nakaoka S.7, Olsen A.8, 17, Park G.-H.9, Peylin P.10, Rodgers K. B.11, Sasse T. P.12, Schuster U.13, Shutler J. D.13, Valsala V.14, Wanninkhof R.15, Zeng J.7
Affiliation(s) 1 : Max Planck Institute for Biogeochemistry, Jena, Germany
2 : Centre for Ocean and Atmospheric Sciences, School of Environmental Sciences, University of East Anglia, Norwich, UK
3 : nstitute for Biogeochemistry and Pollutant Dynamics, ETH Zürich, Zürich, Switzerland
4 : Global Environment and Marine Department, Japan Meteorological Agency, Tokyo, Japan
5 : University of Colorado, Boulder Colorado, USA
6 : Sorbonne Universités (UPMC, Univ Paris 06)-CNRS-IRD-MNHN, LOCEAN/IPSL Laboratory, Paris, France
7 : National Institute for Environmental Studies, Tsukuba, Japan
8 : Geophysical Institute, University of Bergen, Bergen, Norway
9 : East Sea Research Institute, Korea Institute of Ocean Science and Technology, Uljin, Republic of Korea
10 : Laboratoire des Sciences du Climat et de l'Environnement (LSCE), Gif sur Yvette, France
11 : AOS Program, Princeton University, NJ, USA
12 : Climate Change Research Centre, University of New South Wales, Sydney, Australia
13 : College of Life and Environmental Sciences, University of Exeter, UK
14 : Indian Institute of Tropical Meteorology, Pune, India
15 : NOAA/AOML, 4301 Rickenbacker Causeway, Miami, FL, USA
16 : NOAA Earth System Research Laboratory, Boulder Colorado, USA
17 : Bjerknes Centre for Climate Research, Bergen, Norway
Source Biogeosciences (1726-4189) (Copernicus GmbH), 2015-08-27 , Vol. 12 , N. 23 , P. 7251-7278
DOI 10.5194/bg-12-7251-2015
Abstract Using measurements of the surface-ocean CO2 partial pressure (pCO2) and 14 different pCO2 mapping methods recently collated by the Surface Ocean pCO2 Mapping intercomparison (SOCOM) initiative, variations in regional and global sea–air CO2 fluxes have been investigated. Though the available mapping methods use widely different approaches, we find relatively consistent estimates of regional pCO2 seasonality, in line with previous estimates. In terms of interannual variability (IAV), all mapping methods estimate the largest variations to occur in the Eastern equatorial Pacific. Despite considerable spead in the detailed variations, mapping methods with closer match to the data also tend to be more consistent with each other. Encouragingly, this includes mapping methods belonging to complementary types – taking variability either directly from the pCO2 data or indirectly from driver data via regression. From a weighted ensemble average, we find an IAV amplitude of the global sea–air CO2 flux of 0.31 PgC yr−1 (standard deviation over 1992–2009), which is larger than simulated by biogeochemical process models. On a decadal perspective, the global CO2 uptake is estimated to have gradually increased since about 2000, with little decadal change prior to 2000. The weighted mean total ocean CO2 sink estimated by the SOCOM ensemble is consistent within uncertainties with estimates from ocean-interior carbon data or atmospheric oxygen trends.
Full Text
File Pages Size Access
Preprint 56 3 MB Open access
Publisher's official version 28 3 MB Open access
Top of the page

How to cite 

Rödenbeck C., Bakker D. C. E., Gruber N., Iida Y., Jacobson A. R., Jones S., Landschützer P., Metzl N., Nakaoka S., Olsen A., Park G.-H., Peylin P., Rodgers K. B., Sasse T. P., Schuster U., Shutler J. D., Valsala V., Wanninkhof R., Zeng J. (2015). Data-based estimates of the ocean carbon sink variability – first results of the Surface Ocean pCO2 Mapping intercomparison (SOCOM). Biogeosciences, 12(23), 7251-7278. Publisher's official version : , Open Access version :