What would happen if half of the world’s glaciers disappeared, as scientists predict?

First modification: 09/01/2023 – 16:05

Walking on the ice will no longer be more than a memory at the end of the century when many glaciers in Europe and the Andes have disappeared.

According to projections by a group of scientists, published in the journal Science, half of the planet’s glaciers will have disappeared by the end of the 21st century due to global warming. And the number could be worse depending on the amount of greenhouse gases that human activities release into the atmosphere.

If the international community succeeds in limiting global temperature rise to 1.5°C compared to pre-industrial levels – a more optimistic scenario that many no longer consider achievable – researchers estimate that 49% of the world’s glaciers would disappear. This would be equivalent to the disappearance of 26% of the global glacier mass, given that the smallest glaciers are the first to be affected by global warming.

The glaciers of the Alps, the Andes, the Caucasus and the western United States are practically doomed by the increase in global temperatures caused by man, warn scientists in an article published in the prestigious journal Science.

The conclusions of this article confirm the observations of the glaciologist at the Institute for Research and Development (IRD) in France, Antoine Rabatel, who carries out scientific expeditions on Andean glaciers.

“For example, in Bolivia we have the Chacaltaya glacier near the city of La Paz, which finally disappeared at the end of the 2000s. This situation also occurs, for example, in Colombia, in the Santa Isabel snow-capped mountain, where we studied a small glacier and also in Ecuador, where we have a study site on a hill not far from Chimborazo”, details the glaciologist.

“In a scenario of 4 degrees of increase in global temperature, the global loss of ice volume would reach more than 40% of the current mass,” warns Antoine Rabatel from Grenoble. “For example, in the case of small glaciers in the Andes mountain range in the intertropical zone, or in the Alps in France, mountain glaciers could almost completely disappear. Between 70% and 100% of its mass would be lost ”, depending on the climatic trajectory, indicates the glaciologist who makes frequent visits to the alpine glaciers with his students.

Report: The glacier that melts year after year in Chamonix.

Glacier melting causes several large-scale impacts that glaciers are evaluating, in the face of an inexorable worsening of climate change, with effects on different scales, point out the IRD glaciologists. “The rise in sea level could reach up to 11 cm globally, only with the melting of mountain glaciers -not to mention the contribution of Antarctica and Greenland- with an increase of 2.7°C in global temperatures, which is the most realistic scenario”, details Antoine Rabatel.

The disappearance of glaciers also impacts the flow of rivers that participate in human activities, irrigation and electricity production and the functioning of biodiversity.

The authors of the report insist that limiting the disaster will depend on the ambition of the rulers in terms of reducing greenhouse gas emissions.

In this edition of Life on the Planet, discover the promising project of a group of scientists to recover ocean moisture and generate drinking water.

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