A study has revealed a startling forecast: by the middle of this century, thousands of glaciers could disappear each year unless decisive actions are taken to combat climate change. This alarming finding, reported on December 15 in Paris, suggests that without significant intervention, only a small fraction of the world’s glaciers will remain by the end of the century.
The research indicates that government policies aimed at mitigating climate change could drastically influence the future of these ice formations. Specifically, the difference between losing 2,000 and 4,000 glaciers annually hinges on how effectively countries can limit global warming.
Just a few degrees of temperature rise could dramatically alter the fate of glaciers worldwide. The study highlights that maintaining global temperatures at or below 1.5 degrees Celsius above pre-industrial levels could mean nearly half of the world’s glaciers might still exist come 2100, whereas an increase beyond that threshold could reduce their presence to less than 10 percent.
Lander Van Tricht, the lead glaciologist behind this research published in the journal Nature Climate Change, emphasized the critical nature of implementing ambitious climate policies. "Our findings highlight the urgent need for comprehensive action against climate change," he stated, pointing out the impending threat to these vital natural resources.
Unlike typical studies that focus solely on the overall mass and size loss of glaciers, Van Tricht and his team aimed to quantify how many individual glaciers are likely to melt away annually throughout the century. Although smaller glaciers contribute less to sea-level rise compared to their larger counterparts, their disappearance poses significant risks to local tourism and cultural heritage, as noted by the researchers.
Dr. Van Tricht of ETH Zurich and Vrije Universiteit Brussel remarked, "Each glacier that vanishes can have severe local consequences, even if it contributes minimally to meltwater flows."
Co-author Matthias Huss, also a glaciologist at ETH Zurich, shared a poignant experience from 2019 when he participated in a symbolic funeral for the Pizol glacier in the Swiss Alps. "The loss of glaciers is not just a scientific matter; it resonates deeply with us on an emotional level," he explained.
In their study, the scientists analyzed satellite imagery of 211,490 glaciers from a global database to identify when the peak number of glacier losses would occur—a phenomenon they termed "peak glacier extinction." They employed computer models to simulate different climate scenarios, ranging from a modest increase of 1.5 degrees Celsius to a more severe rise of 4 degrees Celsius.
Currently, the planet loses approximately 1,000 glaciers annually, but the research warns that this rate is expected to accelerate rapidly. By 2041, even under the most optimistic scenario of limiting warming to 1.5 degrees Celsius, the annual glacier loss could reach 2,000. If this trend continues, approximately 95,957 glaciers may remain by the year 2100, which is just under half of what exists today.
However, the United Nations has issued warnings that current trajectories indicate a rise in temperatures exceeding the 1.5 degrees Celsius target in the near future. With projections suggesting a potential increase of 2.7 degrees Celsius under existing government policies, around 3,000 glaciers could vanish every year between 2040 and 2060. In a world where temperatures rise to 2.7 degrees Celsius, only about 43,852 glaciers, or one in five, would survive by the end of the century.
In a dire worst-case scenario, with temperature increases reaching 4 degrees Celsius, the annual loss could escalate to 4,000 glaciers by the mid-2050s, leaving a mere 18,288 glaciers, or just nine percent, remaining by 2100.
The timing for peak glacier loss varies widely across different regions, influenced by the size and geographical characteristics of the glaciers. For instance, areas with predominantly smaller glaciers like the European Alps and subtropical Andes could witness the disappearance of half their glaciers within just two decades. In contrast, larger glaciers found in regions like Greenland and the Antarctic may not see peak losses until later in the century.
The researchers noted that while glacier loss will peak across all scenarios, the decline in loss rates only begins as fewer glaciers remain, and the larger ones take longer to melt completely. As Dr. Van Tricht pointed out, the rate of glacier loss in the Alps could eventually taper off to nearly zero by the century’s end, simply because there will be hardly any glaciers left to disappear.
