Seasonal and mesoscale variability of oceanic transport of anthropogenic CO2 ...

• Main Authors: Lachkar, Zouhair, Orr, James C., Dutay, Jean-Claude
• Format: Article in Journal/Newspaper
• Language: English
• Published: ETH Zurich 2009
• Subjects: Orca; Sea ice; Southern Ocean
• Online Access: https://dx.doi.org/10.3929/ethz-b-000019688; http://hdl.handle.net/20.500.11850/19688

Estimates of the ocean's large-scale transport of anthropogenic CO2 are based on one-time hydrographic sections, but the temporal variability of this transport has not been investigated. The aim of this study is to evaluate how the seasonal and mesoscale variability affect data-based estimates of anthropogenic CO2 transport. To diagnose this variability, we made a global anthropogenic CO2 simulation using an eddy-permitting version of the coupled ocean sea-ice model ORCA-LIM. As for heat transport, the seasonally varying transport of anthropogenic CO2 is largest within 20° of the equator and shows secondary maxima in the subtropics. Ekman transport generally drives most of the seasonal variability, but the contribution of the vertical shear becomes important near the equator and in the Southern Ocean. Mesoscale variabilty contributes to the annual-mean transport of both heat and anthropogenic CO2 with strong poleward transport in the Southern Ocean and equatorward transport in the tropics. This "rectified" ... : Biogeosciences, 6 (11) ...