Most glaciers around the world are shrinking as temperatures rise. However, smaller groups behave very differently, and their actions can be much more dangerous.
An international team of scientists led by the University of Portsmouth has completed a major global study of these so-called surging glaciers. This research investigates when and where these sudden events occur, what risks climate change poses, and how climate change is reshaping.
Causes of glacier surge
A glacier surge occurs when normally slowly moving ice suddenly picks up speed. During this period, large amounts of ice are rapidly pushed toward the front of the glacier, often causing it to advance. Such surges can last for several years, and many glaciers cycle repeatedly with long periods of silence.
This research Nature Review Earth and Environmentcompiled data on more than 3,100 glaciers that have experienced surges. They are not evenly distributed around the world, but are concentrated in specific regions such as the Arctic, alpine Asia, and the Andes.
Researchers analyzed how these glaciers work, what conditions cause surges, and where surges are most likely to occur. The study also maps their global distribution and explains why they are concentrated in certain climates.
“Surge-type glaciers are extremely rare and can be troublesome,” said lead author Dr Harold Lovell, a glaciologist and senior lecturer in the School of Environmental and Life Sciences at the University of Portsmouth. “As a friend and fellow glaciologist once said, they store ice like a piggy bank and use it up quickly like a Black Friday event. But although they make up only 1 percent of the world’s glaciers, they affect just under a fifth of the world’s glacier area, and their actions can cause serious, sometimes catastrophic, natural disasters that can affect thousands of people.”
Why surging glaciers are so fragile
The findings show that these glaciers are not protected from climate change. In fact, increased activity can make you more sensitive. Large amounts of ice can be lost during surges, contributing significantly to ice loss in some regions.
Six major dangers associated with glacier proliferation
The study highlights six main dangers that burgeoning glaciers could pose to nearby areas, especially mountainous areas.
- Glacier Advance — Ice can move over buildings, roads, and farmland
- River blockage — Glaciers can dam rivers, forming unstable lakes that can burst and cause severe flooding.
- Meltwater gushes out from beneath glaciers — Sudden releases of water can also cause devastating floods
- Sudden calving of glaciers – these phenomena can lead to large avalanches of ice and rocks
- Extensive crevasses — The rapid movement of glaciers creates deep cracks that make travel extremely dangerous in areas where glaciers are used for routes between settlements, tourism, and mountain climbing.
- Iceberg Hazards — When glaciers rush into the ocean, many icebergs can be rapidly released, posing a risk to shipping and marine tourism.
Using this information, scientists identified 81 glaciers that pose the greatest threat in the event of a surge. Many of these are located in Asia’s alpine Karakoram Mountains, with populated valleys and major infrastructure directly below them. These glaciers tend to be large, close to humans, and prone to repeated overflow.
Climate change increases uncertainty
One of the most worrying conclusions is that rising temperatures are changing the behavior of glacier surges, making it difficult to predict glacier surges at a time when accurate predictions are critical.
“By leveraging previous research, we were able to piece together a growing body of evidence showing how climate change is affecting glacier surges, including where and how often they occur,” said Dr Lovell. “This includes instances where extreme weather events, such as heavy rains and very hot summers, occur earlier than expected, suggesting an increasing unpredictability of their behavior.”
The picture is complex and varies by region. In some places, cases are increasing rapidly and more frequently than in the past. In other regions, the frequency is decreasing. Some glaciers may have become too thin to accumulate enough ice to rise again.
Changing patterns around the world
Glacier growth is currently concentrated in the Arctic and sub-Arctic (48 percent) and Alpine Asia (50 percent), where climatic conditions support this movement. However, as the climate continues to warm, the locations where surges occur may change.
In regions where glaciers are rapidly shrinking, such as in Iceland, the surge could all but disappear. In contrast, warmer weather and increased snowmelt can lead to more frequent storm surges in parts of Asia’s alpine regions and the Arctic regions of Canada and Russia. There is even a possibility that glaciers will proliferate in new areas such as the Antarctic Peninsula.
Co-author Professor Gwen Flowers from Canada’s Simon Fraser University said: “The challenge we face is that just as we are beginning to develop a more comprehensive understanding of the mechanisms behind the rapid increase in glaciers, we are realizing that climate change is rewriting the rules. “This means that extreme weather events that would have been rare even 50 years ago can trigger unexpected glacier surges, making it even more difficult to protect vulnerable communities.”
The need for better monitoring and prediction
Dr Lovell added: “This research is critical because understanding where glaciers are rapidly increasing can help us plan monitoring efforts and understand future actions. Knowing which glaciers pose the greatest risk can help protect communities, especially those most at risk. But increasing unpredictability means we need better monitoring and predictive capabilities.”
Researchers emphasize that continued satellite monitoring, increased in-situ observations during surges, improved modeling, and improved forecasting are essential. These efforts will help scientists understand how burgeoning glaciers respond to continued climate warming and how to reduce the risks they pose to communities around the world.
Important points
- Scientists have identified more than 3,100 burgeoning glaciers around the world, most of which are grouped into major regions such as the Arctic, Alpine Asia, and the Andes.
- Researchers identified 81 glaciers as particularly dangerous, many of them in the Karakoram Mountains, where storm surges can directly impact nearby communities and critical infrastructure.
- Climate change is making these spikes harder to predict because extreme weather events, such as heavy rain or periods of unusually warm weather, can trigger unexpected activity earlier.
