Abstract
We investigate the role of mesoscale eddies in modulating the partial
pressure of CO2 (pCO2) in the Southern Ocean from 1996 to 2015 using an
eddy-centric composite method. The variation of pCO2 is dominated by the
balance between sea surface temperature (SST) and dissolved inorganic
carbon (DIC) effects, which are affected by eddy-induced
upwelling/downwelling. According to the rotation direction and SST
signals, eddies can be classified into warm/cold and
anticyclonic/cyclonic eddies and have different pCO2 anomalies in
different seasons. In winter, the pCO2 anomalies within cold/warm eddies
show positive/negative signals, which are dominated by DIC other than
SST. However, in summer, the mechanisms affecting pCO2 anomalies within
eddies vary with regions in the Southern Ocean. In regions with larger
(smaller) magnitudes of DIC anomalies, the pCO2 anomalies within eddies
are dominated by DIC (SST) anomalies and thus show positive/negative
(negative/positive) signals within cold/warm eddies.