31/01/2025Words by
Rob HutchinsPhotography by
Tetiana GrypachevskaShare31/01/2025New and vital evidence confirming that a dramatic Antarctic ice sheet melt took place some 126,000 years ago will now be critical for predicting how future global warming will impact the region’s vast ice sheets and global sea level rises, a team of scientists behind the discovery have said.By looking at data taken from ice core records, researchers from the British Antarctic Survey and the University of Cambridge have been able to draw new conclusions about how Antarctica was affected by increased temperatures during the last interglacial, some 100,000 years ago. Presenting their findings in the scientific journal Nature this week, these scientists have shown how, during a period of warming, large parts of the West Antarctic Ice Sheet were lost, contributing to significant sea level rises several metres above present. While the melt was dramatic, the same data has shown, however, that the nearby Ronne Ice Shelf – which current climate models project could be lost under future warming scenarios – actually survived.It’s widely recognised that greenhouse gas emissions are warming the Earth at an unprecedented speed and scale. While human-induced global warming has no direct comparable period in the planet’s history, episodic warm periods can offer clues to the future.Led by Eric Wolff from Cambridge University, a team of ice core scientists wanted to find out what happened to the West Antarctic Ice Sheet during the last interglacial, when polar regions were around 3°C warmer than present and sea levels were significantly higher. This is a period in Earth’s history scientists believe is comparable to conditions we might see within decades.“Solving the puzzle of how quickly and how much of the Antarctic ice sheet melted during the last interglacial has been a major goal for paleoclimate researchers for decades,” said Louise Sime, a climate scientist at British Antarctic Survey and a contributing author of the new paper.“By drilling and analysing their new West Antarctic SkyTrain ice core, it seems that Eric Wolff and his team have finally got their hands on key evidence that a large loss of ice really did occur 126,000 years ago.”This is a first for scientists who, for years, have been searching for conclusive data showing such major changes to Antarctica in climate records.“This information from the last time Antarctica was warmer than present day is crucial for predicting how and when the West Antarctic ice sheet will change under future warming,” said Sime.
