A team of more than 60 scientists from 36 institutions used 14 different models to estimate the changes in the ice sheet under two different greenhouse gas emissions pathways: a pessimistic scenario, where there is no change in current trends, leading to a rapid increase in emissions; and an optimistic scenario, where comprehensive steps are taken to reduce emissions. They projected the changes of the Greenland and Antarctic ice sheets between 2015 and 2100 under global warming conditions predicted by the latest climate models. The goal of the research was to estimate how much the mass loss of the ice sheets would contribute to the rise in average sea levels beyond what has already been put in motion.
The study found that by 2100, the Greenland ice sheet would raise sea levels by 4 to 14cm under the pessimistic scenario, but only 1.5 to 5cm under the optimistic scenario.
For the Antarctic ice sheet, the results point to a greater range of possibilities, from ice sheet change that decreases sea level by 7.8cm, to increasing it by 30cm under the pessimistic scenario, with an increase of 0 to 3cm under the optimistic scenario.