The increase in sea ice in Antarctica , caused by the rupture of the floating ice sheet that raises sea level, could have a devastating effect on Earth’s climate, to the point of generating a new glaciation . That is the conclusion of a team of researchers from the University of Chicago that has computer simulated a chain reaction of climate change.
In a study published in ‘Nature Geoscience’ , the researchers presented a new model that details how rising sea ice could change the circulation of the ocean and prevent it from exchanging carbon dioxide with the atmosphere . More carbon dioxide in the ocean and less in the air would lead to a reverse greenhouse effect.
“A key question in this field remains what caused the Earth to periodically enter and exit the glaciations,” explains the University of Chicago professor and co-author of the study, Malte Jansen, in a statement. “We are pretty sure that the carbon balance between the atmosphere and the ocean must have changed, but we don’t know exactly how or why.”
The last major ice age ended at the end of the Pleistocene era, about 2.5 million years ago, as glaciers have grown periodically and then become smaller. The researchers believe that changes in Earth’s orbit may be partly responsible for part of the Earth’s cooling , but additional factors are likely to play a role. “The most plausible explanation is that there was some change in how carbon was divided between the atmosphere and the ocean,” Jansen adds.
Jansen said the Southern Ocean around Antarctica “plays a key role in ocean circulation” due to the deep waters of the area, leading to “huge consequences.” “What this suggests is that it is a feedback cycle, ” explains the lead author of the study, Alice Marzocchi. “As the temperature drops, less carbon is released into the atmosphere, which triggers more cooling.” Understanding the huge role that carbon storage in the ocean plays can help scientists “more accurately simulate future environmental change,” Marzocchi adds.