45 million years from VUW MR

Scientists chart 45 million years of Antarctic temperature change

16 September 2022

Molecular fossils and computer modelling have enabled scientists to build the first catalogue of Antarctic ocean temperatures over the past 45 million years, offering new insights into future sea level changes.

The team, led by scientists from Te Herenga Waka—Victoria University of Wellington, GNS Science, and Birmingham University (UK), says the results provide further evidence we may be nearing a ‘tipping point’ where ocean warming caused by atmospheric carbon dioxide (CO2) will cause a major rise in sea levels as ice sheets melt.

The results are published today (16 September, 2022 NZT) in Nature Geoscience.

“The record we’ve produced shows there is a very clear and direct response of Antarctic temperature to changing atmospheric CO2 throughout geological time,” says Dr Bella Duncan, the study’s lead author.

“Our findings indicate we’ve crossed a threshold where increased CO2 means oceans will warm to a level where there is major ice loss at the marine margins of Antarctic ice sheets, resulting in global sea-level rise over the coming decades and centuries,” she says.

Read Te Herenga Waka—Victoria University of Wellington's media release

1News report: New Antarctica data reveals 'tipping point' for ice melt

The Antarctic Science Platform's Project 1: Ice Dynamics is investigating ice sheet retreat and what is means for sea level rise. The amount and rate of sea level rise in the coming centuries depends on the response of the Antarctica’s marine-based ice sheets, and specifically the West Antarctic Ice Sheet, to warming of the atmosphere and ocean.