Environment

Antarctic emissions cuts seen as last chance to avoid irreversible damage

10:20

By: Dakir Madiha

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Scientists warn that Antarctica’s most accessible region is heading toward irreversible damage unless global greenhouse gas emissions fall sharply within the next few years. Drawing on new modeling of the Antarctic Peninsula, they say decisions made in this decade will lock in environmental changes that will unfold over centuries, reshaping ice, oceans and ecosystems far beyond the polar south.

The research, published in the journal Frontiers in Environmental Science and led by Professor Bethan Davies of Newcastle University, explores how three different emissions pathways would transform the Antarctic Peninsula by 2100 and beyond. The team examined eight core components of the region’s environment, including marine and land ecosystems, sea and land ice, ice shelves, the Southern Ocean, the atmosphere and extreme weather. Under a low-emissions scenario compatible with holding global warming to about 1.8 degrees Celsius above pre-industrial levels, the peninsula would still warm substantially but many of its glaciers and ice shelves would remain largely intact. Under medium-high and very high scenarios, aligned with 3.6 degrees and 4.4 degrees of global warming respectively, the study projects a cascade of impacts ranging from widespread ice-shelf loss to major shifts in food webs.

In the most extreme warming case, the authors describe “long-term and interconnected changes that are irreversible on a human timescale,” including about a 20 percent reduction in winter sea ice cover, collapse of key ice shelves and accelerated retreat of the peninsula’s glaciers. Warmer air and ocean conditions would more than double the average number of days above freezing, pushing liquid precipitation and surface melt into areas that historically remained below zero. The distribution of Antarctic krill, a keystone species that underpins penguin, seal and whale populations, is expected to contract southwards, with knock-on effects across the Southern Ocean food chain. The researchers note that some of these changes, once triggered, would be effectively impossible to reverse within many human lifetimes because of the inertia of the ice–ocean system.

Even the intermediate emissions pathway, which the authors say most closely resembles the world’s current trajectory, delivers outcomes they characterize as deeply disruptive. This scenario still produces sustained ice loss at a faster rate than currently observed, a marked rise in extreme temperature and precipitation events, and localized extinction events in vulnerable habitats. By contrast, in the low-emissions pathway, winter sea ice would shrink only slightly, most glaciers would remain recognizable and bolstering ice shelves would persist, limiting sea level rise from the peninsula itself to only a few millimeters. External experts say the side-by-side scenarios highlight how strongly Antarctica’s fate depends on policy choices taken now, rather than on uncertainties in the science.

The Antarctic Peninsula has already warmed at up to roughly twice the global average, and wider Antarctic studies point to polar amplification strengthening across the continent. At the same time, the Met Office forecasts that average global temperatures in 2026 will sit around 1.46 degrees Celsius above the 1850–1900 baseline, reinforcing how close the world is to the 1.5-degree threshold long framed as a critical guardrail. Researchers stress that physical changes in Antarctica will reverberate worldwide through rising sea levels, altered ocean and atmospheric circulation and disruption of marine food chains that support fisheries and biodiversity far from the Southern Ocean. The study concludes that keeping global warming well below 2 degrees Celsius, and as close as possible to 1.5 degrees, is essential to avoid the most severe and irreversible outcomes in this vulnerable polar region.