This article has been reviewed according to Science X's editorial process and policies. Editors have highlighted the following attributes while ensuring the content's credibility: Cutting greenhouse gas emissions now may limit how much ice Antarctica loses this century and reduce the sea-level rise facing coastal communities, according to findings from a new study. The research, reported in Nature Geoscience by an international team of scientists, including Rutgers climate scientist Robert Kopp, provides evidence that decisions about emissions today can influence how much water Antarctica adds to the oceans by 2100.
The team found at least an 89% probability that the most ambitious low-emission goal consistent with the objectives of the Paris Agreement, an international treaty on climate change adopted in 2015, would result in less Antarctic ice loss by the end of the century than a scenario with very high emissions. "Coastal communities need to prepare for rising seas, and the amount of rise they will have to manage still depends on the choices we make today," said Kopp, a distinguished professor with the Department of Earth and Planetary Sciences in the Rutgers School of Arts and Sciences and an author of the study. "Cutting emissions now can limit the risks facing future generations.
Better projections can help communities decide how to protect homes, roads and other essential infrastructure." The study shows how higher emissions could trigger a series of changes that speed up the movement of Antarctic ice into the ocean. "What we still control is how much, and whether we set off the chain reaction that takes us to the high end," said Yucheng Lin, an assistant professor at the City University of Hong Kong and a former postdoctoral associate in the Department of Earth and Planetary Sciences. "Every ton of greenhouse gas we add makes it worse, and the effect lasts for hundreds of years." The opportunity to limit future damage comes with a sobering finding: Antarctica is very likely to lose ice overall through the end of this century even if nations sharply cut emissions.
The researchers estimated that probability to be at least 92% under the most ambitious scenario, in which the world cuts carbon dioxide emissions to net zero around 2050. Antarctica holds the world's largest store of frozen freshwater. Its enormous ice sheet rests on land, and when that ice moves into the ocean, it adds water and raises sea levels.
Floating shelves of ice along the continent's edges help restrain the glaciers behind them, acting somewhat like brakes. The researchers examined how those brakes could weaken as the climate warms. Warmer ocean water melts ice shelves from below, thinning them, Lin said.
As the shelves weaken or break apart, glaciers can flow more quickly into the sea. How easily the ice slides over the ground beneath it also influences the pace of that loss. Under certain combinations of conditions, these changes can reinforce one another and accelerate the movement of ice into the ocean, he said.
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