Biogeosciences www.biogeosciences.net 1726-4170 1726-4189 6 3 2009 10.5194/bg-6-439-2009 http://www.biogeosciences.net/6/439/2009/ http://www.biogeosciences.net/6/439/2009/bg-6-439-2009.html http://www.biogeosciences.net/6/439/2009/bg-6-439-2009.pdf 439 451 2009-03-18 Anthropogenic carbon distributions in the Atlantic Ocean: data-based estimates from the Arctic to the Antarctic M. Vázquez-Rodríguez F. Touratier C. Lo Monaco D. W. Waugh X. A. Padin R. G. J. Bellerby C. Goyet N. Metzl A. F. Ríos F. F. Pérez Instituto de Investigaciones Marinas, CSIC, Eduardo Cabello 6, 36208 Vigo, Spain IMAGES, Université de Perpignan, 52 avenue Paul Alduy, 66860 Perpignan, France LOCEAN/IPSL, Université Pierre et Marie Curie, case 100, 75252 Paris cedex 05, France Department of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, USA Bjerknes Centre for Climate Research, University of Bergen, Allégaten 55, 5007 Bergen, Norway Geophysical Institute, University of Bergen, Allégaten 70, 5007 Bergen, Norway Five of the most recent observational methods to estimate anthropogenic CO₂ (C_ant) are applied to a high-quality dataset from five representative sections of the Atlantic Ocean extending from the Arctic to the Antarctic. Between latitudes 60° N–40° S all methods give similar spatial distributions and magnitude of C_ant. However, discrepancies are found in some regions, in particular in the Southern Ocean and Nordic Seas. The differences in the Southern Ocean have a significant impact on the anthropogenic carbon inventories. The calculated total inventories of C_ant for the Atlantic referred to 1994 vary from 48 to 67 Pg (10¹⁵ g) of carbon, with an average of 54±8 Pg C, which is higher than previous estimates. These results, both the detailed C_ant distributions and extrapolated inventories, will help to evaluate biogeochemical ocean models and coupled climate-carbon models. % vor jede Referenz A\"ıt-Ameur, N. and Goyet, C.: Distribution and transport of natural and anthropogenic CO₂ in the Gulf of Cadiz, Deep-Sea Res. II, 53, 1329–1343, 2006. Álvarez, M., Pérez, F. F., Shoosmith, D. R., and Bryden, H. L.: The unaccounted role of Mediterranean Water in the draw-down of anthropogenic carbon, J. Geophys. Res., 110, 1–18. doi:10.1029/2004JC002633, 2005. Anderson, L. G., Holby, O., Lindegren, R., and Ohlson, M.: The transport of anthropogenic carbon dioxide into the Weddell Sea, J. Geophys. 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