Heatwaves melt snow cover previously in the season, which exposes darker icy surface areas earlier and accelerates melting.Monitoring Glacier HealthScientists compare glaciers winter season build-ups with summer season losses to track how their mass modifications from year to year– an estimation understood as surface area mass balance (typically measured in meters water equivalent; that is, the depth of water that would result if the ice melted). The Norwegian Water Resources and Energy Directorate keeps a 60-year record of Ålfotbreens mass, which is collected in the field and reported to the World Glacier Monitoring Service.Much of Ålfotbreens surface area is snow that has actually made it through 1– 3 summertimes– known as firn– which is a transition phase to forming glacier ice. Snowy winter seasons led to the ice caps growth between 1989 and 1995, more regular and extreme heatwaves have actually considering that contributed to the glaciers decline.Recent Trends and Concerns”There have been many years recently– in 2017, 2018, 2021, 2022, and 2023, for example– when the glacier lost most of its snow before the melt season ended,” stated Mauri Pelto, a glaciologist at Nichols College.”Global Perspective on Glacier DeclinePelto led an evaluation of World Glacier Monitoring Service mass balance data for 37 mountain glaciers throughout the globe in 2022, and found that 34 of those glaciers had actually lost mass.
Satellite picture of Ålfotbreen glacier in Norway, captured on August 23, 2003. Satellite picture of Ålfotbreen glacier in Norway, captured on September 4, 2022. Resting atop a shingled sandstone landscape, the Norwegian glacier has remained in decrease considering that the late 1990s. Ålfotbreen glacier rests on ledges of sandstone amongst the fjords of Norways western coast. The ice cap is susceptible to changing temperatures and has been in decrease since the late 1990s. Special Geological FormationÅlfotbreen, which is Norways 25th biggest glacier, covers the top of a distinct landscape of shingled sandstone in an area known as the Hornelen Basin. The basin was formed after tectonic plates collided and later on weakened about 400 million years back, in the Devonian period.Sandstone mountain ledges run north to south and are often flanked by cliffs of approximately 100 meters in height. As Ålfotbreen retreats, more of this unique geology is being exposed.Climate Impact on ÅlfotbreenThe glacier sees remarkable swings in its surface area mass between winter and summer season. This is partly due to its place along the western coast, which receives about 600 centimeters (236 inches) of yearly precipitation, making it one of the wettest locations in Europe.Ålfotbreen gains mass as snow builds up over winter season and loses mass as it melts over summer. Heatwaves melt snow cover earlier in the season, which exposes darker icy surfaces earlier and speeds up melting.Monitoring Glacier HealthScientists compare glaciers winter build-ups with summer losses to track how their mass changes from year to year– a computation referred to as surface mass balance (generally determined in meters water equivalent; that is, the depth of water that would result if the ice melted). The Norwegian Water Resources and Energy Directorate maintains a 60-year record of Ålfotbreens mass, which is collected in the field and reported to the World Glacier Monitoring Service.Much of Ålfotbreens surface is snow that has actually endured 1– 3 summer seasons– referred to as firn– which is a transition stage to forming glacier ice. Snowy winter seasons led to the ice caps development in between 1989 and 1995, more extreme and regular heatwaves have actually considering that contributed to the glaciers decline.Recent Trends and Concerns”There have been many years recently– in 2017, 2018, 2021, 2022, and 2023, for example– when the glacier lost most of its snow before the melt season ended,” stated Mauri Pelto, a glaciologist at Nichols College. “This causes glacier decrease as the more long-term ice and firn disappear.”The image set above shows Ålfotbreen during the summer seasons of 2003 (left) and 2022 (right). On August 3, 2003, with more than a month left in the melt season, the glacier had already lost all of its snow cover, which resulted in a large loss of its mass (3 meters of water equivalent). In 2022, the glacier had lost much of its snow cover on September 4, leading to a net mass loss, although not as extreme as 2003. Over the past 10 years (2013-2022), the World Glacier Monitoring Service reports that Ålfotbreen lost approximately 1.07 meters water equivalent each year. In about half of the summers over the past 2 decades, no snow cover remained on the glacier at the end of the melt season. Pelto added, “the absence of a persistent accumulation zone recommends that the glacier can not endure the current climate.”Global Perspective on Glacier DeclinePelto led a review of World Glacier Monitoring Service mass balance information for 37 mountain glaciers across the globe in 2022, and found that 34 of those glaciers had lost mass. The analysis discovered that, typically, glaciers lost more than a meter of ice that year which ice loss from mountain glaciers internationally has been accelerating over time.NASA Earth Observatory images by Wanmei Liang, utilizing Landsat information from the U.S. Geological Survey.