Melting Greenland ice sheet will lead to higher sea level rise than previously predicted
Spanning an area of about 1.8 million km2, the Greenland ice sheet is the largest body of ice in the northern hemisphere, and the second largest in the world after the Antarctic ice sheet. In light of the serious implications of ice loss for the global climate, scientists have been studying the Greenland ice sheet to determine how much it’s likely to melt and how this will actually affect sea levels. A new study supported by the EU-funded MC2 and PROTECT projects has now concluded that the ice sheet is likely to melt about 60 % more by 2100 than previously predicted. This means that sea levels could rise approximately 8 cm higher than earlier estimates used in Intergovernmental Panel on Climate Change (IPCC) reports. The study, whose results were obtained using multiple climate models, has been published in the journal ‘Nature Communications’. One of the climate models used in the research is the Modéle Atmosphérique Régional, or MAR. “While our MAR model suggested that in 2100 the surface melting of the Greenland ice sheet would contribute to a rise in the oceans of around ten centimetres in the worst-case scenario (i.e. if we do not change our habits), our new projections now suggest a rise of 18 cm,” stated Stefan Hofer of MC2 project coordinator University of Oslo in a news item posted on the ‘ScienceDaily’ website.
Downscaling climate scenarios
The findings outlined in the study are expected to be more reliable since they’re based on the most up-to-date models with enhanced physics functionality and spatial resolution. The research team used their MAR regional climate model to downscale the climate scenarios – meaning that high-resolution simulations were used to translate large-scale climate information to regional scales. “It would now be interesting to analyse how these future projections are sensitive to the MAR model that we are developing by downscalling [sic] these scenarios with other models than MAR as we have done on the present climate (GrSMBMIP),” observed co-author Xavier Fettweis of PROTECT project partner University of Liège in the same news item. The results of this study will be included in the IPCC’s Sixth Assessment Report, AR6. The MC2 (Mixed-phase clouds and climate (MC2) – from process-level understanding to large-scale impacts) project is addressing the misrepresentation of cloud phases in global climate models so as to improve climate change predictions on the global scale. Focusing on sea level rise, the PROTECT (PROjecTing sEa-level rise : from iCe sheets to local implicaTions) project aims to produce robust global, regional and local projections of rising sea levels on a range of timescales. The 5-year MC2 project ends in 2023. PROTECT’s 4-year duration concludes in 2024. For more information, please see: MC2 project PROTECT project website
Keywords
MC2, PROTECT, climate, Greenland, ice sheet, sea level rise, MAR model
