Even if global CO2 emissions begin to decline, a large portion of Antarctica is already on a trajectory toward an irreversible melt that many scientists describe as looming. A new study highlights how alarming the situation is and why time is of the essence in understanding its consequences for coastal areas worldwide.
The researchers project that even with a full stop to emissions, it would require hundreds of years for the ice continent to melt completely. In that scenario, sea levels could rise by roughly 1.8 meters, creating profound shifts in where people live and how communities adapt in the future.
Computer simulations were used to estimate the future behavior of ice shelves that shield inland glaciers from warm ocean waters in the Amundsen Sea region of West Antarctica.
In a study published recently in Nature Climate Change, the authors argue that even if a global warming target is held to a modest rise, the impact on ocean warming will still be enough to threaten the stability of the West Antarctic ice sheet.
“The core question is: how much control do we still have over the melting of the ice sheets and how much can actually be prevented by cutting emissions?” said Kaitlin Naughten, an oceanographer with the British Antarctic Survey, in an interview with the Associated Press. This line up confirms the sobering verdict from the simulations showing a rapid acceleration in ocean warming and ongoing ice shelf melt for the rest of the century.
Melting in all possible scenarios
Previous work had already warned about the gravity of the situation, but Naughten was the first to use computer modeling to focus on the below sea level melt of crucial ice shelves. The analysis ran through four distinct scenarios, each tied to the amount of carbon dioxide released into the atmosphere. Across every scenario, warming of the ocean was substantial, casting doubt on the survival of this part of the ice sheet.
Naughten highlighted the key ice shelves that act as barriers for inland glaciers. When these shelves weaken, there is little to prevent the glaciers behind them from slipping into the ocean, raising global sea levels.
Naughten examined what would happen if future warming could be limited to a rise of 1.5 degrees Celsius above late nineteenth century levels, a widely cited international target. The study found that even under that more modest warming, extreme melting becomes likely. The current warming level has already exceeded that threshold recently during summer.
Naughten’s focus was on the West Antarctic region near the Amundsen Sea, among the most vulnerable to below sea level melt. This includes the Thwaites Ice Shelf, which has drawn attention as a critical barrier to inland glaciers. West Antarctica is smaller than the eastern part of the continent but behaves in a more unstable manner.
“The damage has already been done”
This portion of Antarctica is described as doomed to fail by multiple researchers. Eric Rignot, a climate scientist at the University of California, Irvine, who was not involved in the new work, summed up the sentiment with a concise assessment. Ted Scambos, a colleague at the University of Colorado, also stressed that the ice sheet will eventually disappear, though he added that this is not a happy forecast and comes with reluctance.
Naughten has reservations about labeling the region as doomed. He notes that the current trajectory points to a slow collapse that extends beyond this century. While it is unlikely that the entire area can be saved, the exact pace of change remains uncertain.
The study does not quantify precisely how much ice will vanish or the exact rate of sea level rise, but it estimates that if the most vulnerable portion were to melt, global sea levels could rise around 1.8 meters. The scenario points to a century or more of gradual change before stabilizing, suggesting a long road ahead for adaptation. Long-term projections extend into the 22nd and 23rd centuries
The implications of such a rise would be devastating if it occurred within a couple of centuries, whereas a slower pace would allow more time for society to adapt. The work references the scientific record and a DOI for further reading, and it emphasizes the need for ongoing observation and modeling to refine understanding of these slow, cumulative processes.
Endnotes and references to the broader climate literature provide additional context for policymakers and researchers seeking to interpret the potential path of Antarctic ice loss and its global repercussions.