Two-metre sea level rise would have 'profound impact on humanity'

22 May 2019, 10:27 | Updated: 22 May 2019, 11:00

Global sea levels could rise by more than two metres causing catastrophic consequences for the world, according to a team of scientists.

Such a rise could result in the loss of 1.79 million km2 of land, including critical regions of food production, and the potential displacement of up to 187 million people.

Traditional methods for predicting rising sea levels from the melting ice sheets in Greenland and the Antarctic are based on numerical modelling, but these remain challenging due to changing factors.

A team of international scientists used a technique called structured expert judgement to ask 22 ice sheet experts to estimate plausible ranges for future sea level rises.

They asked them to consider the projected melting of each of the Greenland, West Antarctic and East Antarctic ice sheets under low and high future global temperature rise scenarios.

Lead author professor Jonathan Bamber, from the University of Bristol, said: "Structured expert judgement provides a formal approach for estimating uncertain quantities based on current scientific understanding, and can be useful for estimating quantities that are difficult to model.

"Projections of total global subsequent sea level rise using this method yielded a small but meaningful probability of subsequent sea level rise exceeding two metres by the year 2100 under the high temperature scenario, roughly equivalent to 'business as usual', well above the 'likely' upper limit presented in the Fifth Assessment Report of the Intergovernmental Panel on Climate Change."

Prof Bamber added: "Such a rise in global sea level could result in land loss of 1.79 million km2, including critical regions of food production, and potential displacement of up to 187 million people.

"A subsequent sea level rise of this magnitude would clearly have profound consequences for humanity."

The study is published in the journal Proceedings of the National Academy of Sciences of the United States of America.

:: Sky's Ocean Rescue campaign encourages people to reduce their single-use plastics. You can find out more about the campaign and how to get involved at www.skyoceanrescue.com.