Antarctica, Greenland ice sheet melting matches worst-case climate change scenarios
Increasing melting rates for ice sheets in Antarctica and Greenland match worst-case scenarios for climate warming, potentially exposing 16 million people to annual coastal flooding by the end of the century, warned a new study.
- The global sea level rose by 1.8 centimetres because of the rapid melting rates of the ice sheets since the 1990s.
- Increasing melting rates will raise sea levels by a further 17 cm, according to the study led by Tom Slater from the Centre for Polar Observation and Modelling at the University of Leeds, United Kingdom.
- Melting from Antarctica pushed sea levels up by 7.2 millimetres, while Greenland accounted for 10.6 mm, with latest measurements pointing out a rise in the world’s oceans by four mm every year.
- The study — published in journal Nature Climate Change August 31, 2020 — compared the latest results from satellite surveys from the Ice Sheet Mass Balance Intercomparison Exercise (IMBIE), with calculations from climate models.
- One of the primary causes for the rise in global sea levels was thermal expansion, involving the volume of seawater expanding once it gets warmer.
- Ice melt from ice sheets and mountain glaciers, however, overtook global warming as the main cause of rising sea levels in the past five years.
- Ice sheets lost ice at rates predicted by the worst-case scenarios put forth in the last report by the Intergovernmental Panel on Climate Change, warned the authors.
- The 17 cm-rise in sea levels from ice sheets alone was enough to double the frequency of storm-surge flooding in the largest coastal cities, said Anna Hogg, a co-author and climate researcher in the School of Earth and Environment at Leeds.
- Ice sheets from Antarctica and Greenland were not the only ones causing water rise, according to Ruth Mottram, study co-author and climate researcher at the Danish Meteorological Institute.
- The IMBIE is a joint collaboration established between scientists supported by the European Space Agency and the United States’ National Aeronautics and Space Administration in 2011.