Temporal variability of the anthropogenic CO2 storage in the

• Main Authors: Irminger Sea, F. F. Pérez, E. Louarn, X. A. Padı́n, H. Mercier, A. F. Rı́os
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2008
• Subjects: Irminger Basin; Irminger Sea; Labrador Sea; North Atlantic; North Atlantic oscillation
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.626.2354; http://archimer.ifremer.fr/doc/2008/publication-5925.pdf

Abstract. The anthropogenic CO2 (Cant) estimates from cruises spanning more than two decades (1981–2006) in the Irminger Sea area of the North Atlantic Sub-polar Gyre reveal a large variability in the Cant stor-age rates. During the early 1990’s, the Cant storage rates (2.3±0.6 mol C m−2 yr−1) doubled the average rate for 1981–2006 (1.1±0.1 mol C m−2 yr−1), whilst a remark-able drop to almost half that average followed from 1997 onwards. The Cant storage evolution runs parallel to chlorofluorocarbon-12 inventories and is in good agreement with Cant uptake rates of increase calculated from sea sur-face pCO2 measurements. The contribution of the Labrador Seawater to the total inventory of Cant in the Irminger basin dropped from 66 % in the early 1990s to 49 % in the early 2000s. The North Atlantic Oscillation shift from a positive to a negative phase in 1996 led to a reduction of air-sea heat loss in the Labrador Sea. The consequent convection weakening accompanied by an increase in stratification has lowered the efficiency of the northern North Atlantic CO2 sink. 1