The reinvigoration of the Southern Ocean carbon sink

Peter Landschützer , Nicolas Gruber , F. Alexander Haumann , Christian Rödenbeck (1) , Dorothee C. E. Bakker , Steven M. A. C. van Heuven , Mario Hoppema , Nicolas Metzl (2) , Colm Sweeney , Taro Takahashi , Bronte Tilbrook , Rik H. Wanninkhof (3)

1 Biogeochemical Systems Department [Jena]
2 E-CO2 - Équipe CO2
3 AOML - NOAA Atlantic Oceanographic and Meteorological Laboratory

Several studies have suggested that the carbon sink in the Southern Ocean—the ocean’s strongest region for the uptake of anthropogenic CO₂ —has weakened in recent decades. We demonstrated, on the basis of multidecadal analyses of surface ocean CO₂ observations, that this weakening trend stopped around 2002, and by 2012, the Southern Ocean had regained its expected strength based on the growth of atmospheric CO₂. All three Southern Ocean sectors have contributed to this reinvigoration of the carbon sink, yet differences in the processes between sectors exist, related to a tendency toward a zonally more asymmetric atmospheric circulation. The large decadal variations in the Southern Ocean carbon sink suggest a rather dynamic ocean carbon cycle that varies more in time than previously recognized.

Domaines: Géophysique [physics.geo-ph]

Peter Landschützer, Nicolas Gruber, F. Alexander Haumann, Christian Rödenbeck, Dorothee C. E. Bakker, et al.. The reinvigoration of the Southern Ocean carbon sink. Science, 2015, 349 (6253), pp.1221-1224. ⟨10.1126/science.aab2620⟩. ⟨hal-01200529⟩