Two-thirds of the Earth’s glaciers are on track to disappear by 2100

EAbout 50% of all glaciers on the planet and up to 83% are at risk of disappearing by the end of the century due to climate change. However, the fight against global warming can still protect the rest.

GIF Caption: Between 1973 (left) and 2022 (right), the ice in Greenland darkens and then shrinks as the glaciers thin. (NASA)

This is what emerges from a recent study (link below), accompanied by a very comprehensive overview of the condition of 215,000 glaciers worldwide.

The researchers stressed the importance of limiting greenhouse gas emissions to minimize the consequences of melting glaciers, such as water depletion and sea level rise. To help guide policy, the study focused on four specific scenarios and their impact on glaciers, where global temperature change averages 1.5, 2.0, 3.0 and 4.0 degrees Celsius.

Study co-author Regine Hock from the University of Oslo and the University of Alaska Fairbanks (USA) notes that a difference of just one degree results in more loss and melting. However, Hoke also notes that this means that if temperature increases are reduced, mass losses may also be reduced.

The world is currently on track to rise by about 2.7°C since pre-industrial times. According to experts’ estimates, about 49% of the world’s glaciers will disappear by 2100. This will affect about 26% of the world’s glacier mass, with the smallest glaciers being the first to be affected.

Regions with virtually no ice, such as the Caucasus, the Andes, the European Alps, and the western United States, are set to lose almost all of their ice by the end of the century, regardless of emissions, Regine Hock notes. situation. He notes that these glaciers are mostly doomed.

Chunks of ice float in front of the Mendenhall Glacier on Lake Mendenhall in Juneau, Alaska, Monday, May 30, 2022. (AP/Becky Bohrer)

The worst possible scenario would be a temperature increase of 4.0°C. In this case, large glaciers will be affected, including those in Alaska. This would mean that about 83% of the world’s glaciers could be gone by 2100, and their loss would naturally exacerbate sea-level rise.

Photos from September 14, 1986, left, and August 1, 2019, provided by NASA, show the receding Okjokull glacier at the Ok volcano in west-central Iceland. A geological map from 1901 estimated that Okjökull covered an area of ​​about 38 square kilometers. In 1978, aerial photographs showed that the glacier was 3 square kilometers. In 2019, there is less than one square kilometer left. (NASA/PA)

Hoke further states that the studied glaciers make up only 1% of the planet’s ice. This is much less than the ice sheets of Antarctica and Greenland. However, these glaciers are responsible for nearly as much sea level rise in the past three decades as in Greenland and Antarctica. A rise of 1.5°C would result in an average sea level rise of 9 cm, and a rise of 4°C would result in a rise of 15 cm.

While this may seem important, global sea level is not a major concern. These increases are due to storm surges that can cause serious damage.

The loss of glaciers will also affect water supplies, as they serve as a source of fresh water for nearly two billion people. These glaciers compensate for water loss during the summer months, when there is no rain and high temperatures.

These predictions have been made through decades of glacier mass analysis and computer simulations. While these results are alarming, Hoke notes that it is still possible to reduce this loss with effort. But their realization is another matter. These efforts are still in the hands of leaders and politicians.

Science: Global glacier change in the 21st century: Every rise in temperature matters, and study published on the Carnegie Mellon University website: Team projects two out of three glaciers could be lost by 2100.