A new analysis of ancient layers of peat at the bottom of the North Sea will help scientists more accurately project how much sea level will rise in the coming decades and centuries. The research shows how fast sea level rose about 11,000 years ago, at the end of the last ice age, the last time Earth warmed as fast as it is warming now.

Current estimates for sea level rise in the next 75 years range between 1 and 4 feet. The new study, published today in Nature, affirms that projections for 3 feet of sea level rise by 2100 are not unrealistic, and "help[s] unravel the complex interaction between ice sheets, climate, and sea level," said co-author Marc Hijma, a geologist with Deltares, a nonprofit research institute in The Netherlands.

The findings suggest sea level jumped by as much 3.3 feet per century during at least two separate periods between about 8,300 and 10,300 years ago, as the North American and Eurasian ice sheets melted away early in the Holocene geologic era. Previous estimates for the total amount of sea level rise in the early Holocene varied by as much as 50 feet.

"The uncertainty was just enormous for this time period ... because of a lack of good data," said Hijma, adding that pinpointing future sea level rise is critical for coastal communities trying to prepare themselves. "This provides insights for both scientists and policymakers, so that we can prepare better for the impacts of current climate change, for example by focusing on climate adaptation," he said.

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https://insideclimatenews.org/news/19032025/rapid-sea-level-rise-during-last-ice-age/