snows

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.

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Team projects two out of three glaciers could be lost by 2100

Ice, Snow, and Glaciers and the Water Cycle

Photo, posted August 13, 2010, courtesy of Kimberly Vardeman via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Glaciers represent the snows of centuries compressed over time to form flowing rivers of ice. Glaciers always change, accumulating snow in the winter and losing ice to melting in the summer. But in recent times, the melting has been outpacing the accumulation.

Glaciers are a sensitive indicator of climate change. They have been melting at a high rate since the mid-20th century – regardless of altitude or latitude. But up until recently, the full extent of glacial ice loss has only been partially measured and understood.

Now, according to new research led by scientists from ETH Zurich in Switzerland and the University of Toulouse in France, nearly all the world’s glaciers are becoming thinner and losing mass. And the changes are accelerating. The study, which is the most comprehensive and accurate of its kind to date, is the first to include all the world’s glaciers – around 220,000 in total – excluding the Greenland and Antarctic ice sheets. The research team’s findings were recently published in the journal Nature.

Between 2000 and 2019, the world’s glaciers lost an average of more than 294 billion tons of ice per year. Between 2000 and 2004, glaciers lost an average of about 250 billion tons of ice each year. But between 2015 and 2019, ice mass loss jumped up to an average of approximately 328 billion tons annually.

Glacial melt is responsible for 21% of the observed sea level rise during this two decade time period studied.

This research is just another reminder of how we need to act urgently if we want to prevent the worst-case climate change scenario from becoming a reality.

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Global glacier retreat has accelerated

Photo, posted September 17, 2015, courtesy of Richard Whitaker via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Disappearing Glaciers | Earth Wise

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.

Web Links

Accelerating Global Glacier Loss | Earth Wise

Glaciers represent the snows of centuries compressed over time to form flowing rivers of ice. Glaciers always change, accumulating snow in the winter and losing ice to melting in the summer. But in recent times, the melting has been outpacing the accumulation.

Web Links