Glaciers are massive bodies of slowly moving ice. Glaciers form on land, and represent the snows of centuries compressed over time. They move slowly downward under the influence of their own weight and gravity.
Most of the glaciers on the planet are found in the polar regions, including Antarctica, the Canadian Arctic, and Greenland. Glaciers can also be found closer to the equator in mountain ranges, such as the Andes Mountain range in South America. Glaciers are always changing, accumulating snow in the winter and losing ice to melting in the summer. But in recent times, the melting has been outpacing the accumulation.
A new international study led by researchers at Carnegie Mellon University’s College of Engineering has produced new projections of glacier loss through the century under different emissions scenarios. According to the projections, the world could lose as much as 41% of its total glacier mass this century – or as little as 26% – depending on climate change mitigation efforts.
In a future with continued investments in fossil fuels (sometimes referred to as the “business as usual” scenario), more than 40% of the glacial mass will be gone by 2100, and more than 80% of glaciers by number could disappear. Even in a best case scenario where the increase in global mean temperature is limited to 1.5° degrees Celsius relative to pre-industrial levels, more than 25% of glacial mass will be gone, and nearly 50% of glaciers by number will disappear.
Glaciers take a long time to respond to changes in climate. A complete halt to emissions today would take anywhere from 30 to 100 years to be reflected in glacier mass loss rates.
Photo, posted August 13, 2010, courtesy of Kimberly Vardeman via Flickr.