Final meeting of ice2sea highlights sophisticated new modelling techniques to measure ice-melt contribution to future sea-level rise
PR No. 07/2013
On Wednesday, 15th May scientists from the major European Union programme ice2sea met in London at the Royal Institution of Great Britain to discuss four years of research into how to better understand and model ice-melt and its contribution to sea-level rise.
Stakeholders have been presented with a document that summarises the work done and key findings from more than 150 ice2sea scientific papers published since 2009 in respected scientific journals around the world.
The programme was born out of an urgent call for research by the international community following the last Intergovernmental Panel on Climate Change report (IPCC AR4) in 2007, which identified the uncertainty in projections of ice-sheet contributions to sea-level rise as a key problem that must be addressed.
Professor David Vaughan, of the British Antarctic Survey who is the coordinator of the ice2sea programme says,
“Today, as the glaciers and ice sheets lose their ice, the water that they once held has melted and flowed in to rivers and seas, increasing their volume and raising global sea-levels. Current rates of sea-level rise are already having impacts on the most vulnerable communities and ecosystems.
“It is likely that some future ice-loss and sea-level rise is now unavoidable. But nevertheless, understanding why changes are occurring today and how they could increase in the future is the first step in maintaining the security of our coastal regions for future generations.”
The new ice2sea report’s summary of outcomes states,
“Ice2sea has reduced uncertainty in the contribution of ice sheets and glaciers to sea-level projections by: making key measurements of current changes; improving understanding of their causes; and by developing new methods for projection. Ice2sea has established a substantial European capability in sea-level projection, has identified where the remaining uncertainties exist, and which key processes are still not fully understood.”
The programme has combined expertise across a wide range of scientific disciplines which has enabled contributors to develop projections of continental ice-loss using computer models that are based exclusively on simulations of the physics at work in glaciers and ice sheets.
The ice2sea projections based on simulations of physical processes suggest lower overall contributions from melting ice to sea-level rise than many studies published since AR4.
They suggest a contribution from continental ice of 3.5-36.8cm to global mean sea-level rise to the year 2100 for a “business as usual” mid-range emissions scenario.
To obtain a projection of total global sea-level rise, other contributions, not explicitly addressed by ice2sea, must be added (for instance thermal expansion of the oceans, and changes in terrestrial water storage). For the period after 2100, sea levels will continue to rise, initially at an accelerating rate, for many centuries.
These numbers represent the state-of-the-art in projections based on a clearer understanding of the physics, but inevitable uncertainties remain both in how the climate is expected to change over the century, and in the ice sheets’ response.
To explore these remaining uncertainties, ice2sea has used a less-formal approach of an “expert elicitation.” This method concluded that there is a less than 1-in-20 risk of the contribution of ice sheets to global sea-level rise exceeding 84cm by 2100.
Several factors cause local and regional sea level to differ by as much as tens of centimetres to the global mean. Ice2sea has investigated the pattern of this variation and its simulations of ice loss indicate that European coastlines will experience a sea-level rise of 10-20% less than the global mean.
However, sea-level rise needs to be taken together with known patterns of vertical land movement, and projected changes in ocean circulation and storminess. These indicate that 50-year extreme storm-surge events could approach 1 metre higher than at present on some European coasts.
Other key aspects of the ice2sea programme have been to enable the production of the first projections of the contribution of continental ice (glaciers and ice sheets) based solely on physically-based models and tied to specific scenarios of greenhouse gas emissions. It has also identified and trained a new generation of young scientists with the insight, skills, and collaborative networks to take the science of sea-level projection forward in future decades.
ENDS
The report From Ice to High Seas is available here.
To request an interview with Professor David Vaughan, Professor Jonathan Bamber or Professor Tony Payne please contact Paul B. Holland at the British Antarctic Survey Communications Office, Cambridge. Tel: +44 (0)7771 905977; Email: paul.b.holland@bas.ac.uk.
Notes to editors:
Ice2sea brings together the EU’s scientific and operational expertise from 24 leading institutions across Europe and beyond. Improved projections of the contribution of ice to sea-level rise produced by this major programme funded by the European Commission’s Framework 7 Programme (grant agreement 226375) will inform the fifth IPCC report (due in 2013). In 2007, the fourth Intergovernmental Panel on Climate Change (IPCC) report highlighted ice-sheets as the most significant remaining uncertainty in projections of sea-level rise.
Europe’s coastline: Fifteen EU countries have substantial coastlines. Economic assets within 500 m of the sea have an estimated value between €500 and €1,000 billion. Some 47,500 Km2 of sites within 500m of the coastline are identified as having high ecological value. Around 70 million people live close to the coast in Europe.
Free talk: ice2sea scientists will present a free public talk and Q&A session on Thursday (May 16th) at the Royal Institution of Great Britain (Faraday Lecture Theatre), 21 Albemarle Street, London, W1S 4BS, called “From Ice to High Seas: Future Sea-level rise and its impact on London”. The event starts at 7pm and entrance is free. For more information please contact the ice2sea programme office at the British Antarctic Survey via email: ice2sea@bas.ac.uk.
