The melting of the ice sheet at the end of the last Ice Age may have caused sea levels to rise ten times faster than it is now, according to a study published Thursday by a team led by scientists at the British University of Durham.
Based on geological data, the researchers estimate that worldwide oceans rose 3.6 meters (11.8 feet) per century over 500 years, some 14,600 years ago.
The findings raise a red flag about today’s potential for rapid sea-level rise that could engulf coastal cities and densely populated deltas around the world.
The team found that the roughly 18-meter sea-level rise may have been mainly from melting ice sheets in the Northern Hemisphere and not Antarctica, as previously thought.
The scientists say their work could provide “vital clues” about future ice sheet melting and sea level rise due to climate change.
“We found that most of the rapid sea-level rise was due to the melting of ice sheets in North America and Scandinavia, with a surprisingly small contribution from Antarctica,” said study co-author Pippa Whitehouse of the department. geography from Durham University.
“The next big question is to find out what triggered the ice melt, and what impact the massive inflow of meltwater had on the ocean currents in the North Atlantic.
“This is our view today – any disturbance to the Gulf Stream, for example from the melting of the Greenland ice sheet, will have a significant impact on the UK climate.”
Current models used by many climate scientists estimate that global sea levels could rise by 1 to 2 meters by the end of this century.
The Durham researchers used detailed geological sea level data and state-of-the-art modeling techniques to reveal the sources of the dramatic five-century sea level rise.
Similar to the melting of an ice sheet twice the size of Greenland, it resulted in the inundation of vast low-lying areas and disrupted ocean circulation, affecting the global climate, they said.
“Our study provides new information from lakes around the coast of Scotland that were isolated from the ocean as a result of inland force following the retreat of the British Ice Sheet, allowing us to confidently identify meltwater sources,” co-author Yucheng Lin also added . from Durham’s Geography Department.
Identifying the source of the meltwater will help improve the accuracy of climate models used to replicate the past and predict changes in the future, the team added.
They noted that the findings were particularly timely, as Greenland’s ice sheet is rapidly melting, contributing to rising sea levels and changes in global ocean circulation.
In 2019, Greenland shed more than half a trillion tons of ice and meltwater, accounting for 40 percent of the total sea level rise that year.
© Agence France-Presse