Climate-Driven Changes to the Atmospheric CO sub(2) Sink in the Subtropical North Pacific Ocean

The global ocean is recognized as an important sink for atmospheric carbon dioxide. Analyses have indicated that variability in the strength of this sink is evident on interannual timescales due to regional and basin-scale changes in the physical and biological parameters that govern the flux of carbon dioxide into and out of the surface mixed layer. Findings are reported from an analysis of a 13-year time series of oceanic carbon dioxide measurements obtained from station ALOHA in the subtropical northern Pacific Ocean, near Hawaii. Evidence indicated a significant reduction in the strength of the carbon dioxide sink over the period 1989-2001. A significant fraction of this reduction can be linked to an increase in the partial pressure of the surface ocean carbon dioxide due to excess evaporation and associated concentrations of solutes in the water mass.