Ancient peat reveals that sea level surged rapidly twice at the end of the last ice age

By Nicole S. Khan – nature.com

An analysis of peat from ancient wetlands provides a reconstruction of how sea level increased millennia ago — and how it might rise again with global warming.

As Earth warms, ice sheets will melt and sea levels will rise at rates projected to surpass those of the past several thousand years. The last time the planet experienced such rapid sea-level rise was 11,700 to 8,200 years ago — during the early Holocene, the beginning of the current geological epoch — as the planet transitioned out of the last ice age. Detailed records from ancient periods such as the early Holocene are needed to constrain estimates of future sea-level rise, but the records are sparse and uncertain. Writing in Nature, Hijma et al. address this knowledge gap by producing an early-Holocene sea-level record from the North Sea that has unprecedented temporal resolution. The findings provide fresh insight into how ice sheets melted and sea level rose during the final stages of deglaciation, bolstering understanding of how the Earth system responds to climate change and re-shapes the world.