New research findings underline the crucial role that sea ice throughout the Southern Ocean played for atmospheric CO2 in times of rapid climate change in the past.
New research findings underline the crucial role that sea ice throughout the Southern Ocean played for atmospheric CO2 in times of rapid climate change in the past. An international team of scientists with the participation of the University of Bonn has shown that the seasonal growth and destruction of sea ice in a warming world increases the biological productivity of the seas around Antarctica by extracting carbon from the atmosphere and storing it in the deep ocean. This process helps to explain a long-standing question about an apparent 1,900-year pause in CO2 growth during a period known as the Antarctic cold reversal. The research results have now been published in "Nature Geoscience".
Surrounding the remote continent of Antarctica, the Southern Ocean is one of the most important yet poorly understood components of the global carbon cycle. Having captured half of all human-related carbon that has entered the ocean to date, the Southern Ocean is crucial to regulating human-induced CO2. Therefore, understanding the processes that determine its effectiveness as a carbon sink through time are essential to reducing uncertainty in climate projections.
After the Last Ice Age, around 18,000 years ago, the world transitioned naturally into the warm interglacial world we live in today. During this period, CO2 rose rapidly from around 190 ppm to 280 ppm over around 7,000 years. This rise was not steady, and was interrupted by rapid rises and intermittent plateaus, reflecting different processes within the global carbon cycle.
Read more at University Of Bonn
Image: Drilling camp in the Horseshoe Valley with flat drill in the foreground. CREDIT: Chris Turney
