There is now important evidence that the rise in atmospheric carbon dioxide levels at the end of the last ice age was triggered by changes in the Antarctic Ocean. The Southern Ocean plays an important role in climate events because CO2 can be absorbed from the atmosphere into the ocean.
When increased amounts of dust are deposited in the seawater, microscopic algae multiply because the iron contained in the dust acts as a fertilizer. When these single celled algae die, they sink to the ocean floor, taking the sequestered carbon dioxide with them. To ensure long-term removal of the CO2 from the atmosphere, however, it must be stored in stable conditions in deep water over long periods of time.
The study was carried out by a team from Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research. For some time now climate researchers have been speculating on why fluctuations in atmospheric CO2 levels followed the same pattern as temperature in the southern hemisphere whereas the temperature in the north at times ran counter to these fluctuations. One theory is that certain processes in the Southern Ocean played an important role.