Changing Antarctic Waters 'Disturbingly Similar' to Conditions of 14,000 Years Ago

Could we be close to a steep rise in sea levels? Scientists have found that current changes in the ocean around Antarctica are disturbingly similar to conditions that occurred 14,000 years ago and resulted in an abrupt 3 to 4 meter rise in the global sea level.

When ocean temperatures around Antarctica became more layered in the past, ice sheets and glaciers melted much faster than when the cool and warm waters mixed more easily.  This particular, defined layer is currently occurring around the Antarctic. Global warming is causing land-based ice to melt, which is adding freshwater to the surface of the ocean. This freshwater prevents mixing and causes a distinct layer between temperatures.

"At the same time as the surface is cooling, the deeper ocean is warming, which has already accelerated the decline of glaciers on Pine Island and Totten," said Matthew England, one of the authors of the new paper, in a news release. "It appears global warming is replicating conditions that, in the past, triggered significant shifts in the stability of the Antarctic ice sheet."

The new research comes after scientists created model simulations of the last time this occurred, about 14,000 years ago. At the time, the Antarctic alone contributed three to four meters to global sea levels in just a few centuries.

"Our model simulations provide a new mechanism that reconciles geological evidence of past global sea levels rise," said Chris Fogwill, one of the researchers. "The results demonstrate that while Antarctic ice sheets are remote, they may play a far bigger role in driving past and importantly future sea level rise than we previously suspected."

The findings are important as our climate continues to change. Currently, the scientists want to investigate whether the ice sheet will react as quickly as it did 14,000 years ago. This is especially important to note since such a dramatic rise in sea levels would impact the 700 million people worldwide that live less than 10 meters above the present sea level.

The findings are published in the journal Nature Communications.