Public Release: 

Sea level rise from Antarctic collapse may be slower than suggested

Impact on sea level of Antarctic ice sheet collapse

British Antarctic Survey

A new study by scientists in the UK and France has found that Antarctic ice sheet collapse will have serious consequences for sea level rise over the next two hundred years, though not as much as some have suggested.

This study, published today in the journal Nature, uses an ice-sheet model to predict the consequences of unstable retreat of the ice, which recent studies suggest has begun in West Antarctica. Scientists, led by Catherine Ritz from Université Grenoble Alpes in France and Tamsin Edwards from The Open University, predict that the contribution is most likely to be 10 cm of sea-level rise this century under a mid to high climate scenario, but is extremely unlikely to be higher than 30 cm. When combined with other contributions, that's a significant challenge for adapting to future sea level rise. But it's also far lower than some previous estimates, which were as high as one metre from Antarctica alone.

The study's central estimate raises the Intergovernmental Panel on Climate Change (IPCC) central prediction of 60 cm global sea-level rise by just a few centimetres under the mid to high scenario they used. But the UK and France team's method allowed them to assess the likelihood of sea-level rise from substantial parts of the ice sheet collapsing, which the IPCC could not due to a lack of evidence. They predict there is a one in twenty chance that Antarctic collapse could contribute more than 30 cm sea-level rise by the end of the century and more than 72 cm by 2200. This does not rule out larger contributions on longer time scales.

Lecturer in Environmental Sciences at the OU, Dr Edwards says "Our method is more comprehensive than previous estimates, because it has more exploration of uncertainty than previous model predictions and more physics than those based on extrapolation or expert judgement."

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The paper 'Potential sea-level rise from Antarctic ice sheet instability constrained by observations' is authored by Catherine Ritz (Centre national de la recherche scientifique and Université Grenoble Alpes, France), Tamsin L. Edwards (The Open University, University of Bristol), Gaël Durand (Centre national de la recherche scientifique and Université Grenoble Alpes, France), Antony J. Payne (The University of Bristol), Vincent Peyaud (Centre national de la recherche scientifique and Université Grenoble Alpes, France) and Richard C.A. Hindmarsh (British Antarctic Survey). It has been published today (Wednesday 18 November 2015) in the academic journal Nature.

OU Media contact:

Email: Rebecca.Wilhelm@open.ac.uk

Direct line: 01908 654 565

General press office: 01908 654 316

Out of hours enquiries: 07901 515891

For media enquiries before 17 Nov, please contact Prof Tony Payne (A.J.Payne@bristol.ac.uk) or Dr Catherine Ritz (catherine.ritz@lgge.obs.ujf-grenoble.fr). For media enquiries from 18 Nov, or to arrange interviews for that period, contact Dr Tamsin Edwards - otherwise tamsin.edwards@open.ac.uk

Notes to the editor

1. To read the full paper 'Potential sea-level rise from Antarctic ice sheet instability constrained by observations' please visit the Nature website: http://dx.doi.org/10.1038/nature16147 [NOTE: the URL will go live after the embargo ends]

2. Caption for accompanying image: Dumont d'Urville Station, Coastal Antarctica. Credit: Bruno Jourdain, CNRS

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