All 19 of the world's glacier regions experienced a net loss of mass in 2024, for the third consecutive year, the United Nations said on Friday. It has declared 21 March World Day for Glaciers, warning that at current rates of melting, many glaciers "will not survive the 21st century".
A sign indicates the level of the Mer de Glace glacier in 1990, at Chamonix in the French Alps, pictured in June 2019. AFP/Marco Bertorello
By: RFI
Issued on: 21/03/2025
Five of the last six years have seen the most rapid glacier retreat on record, the UN's World Meteorological Organisation (WMO) said, on its inaugural World Day for Glaciers.
"Preservation of glaciers is a not just an environmental, economic and societal necessity: it's a matter of survival," said WMO chief Celeste Saulo.
"From 2022 to 2024, we saw the largest three-year loss of glaciers on record," she said, adding that the worst year was 2023.
Together, "all 19 glacier regions lost 450 billion tonnes of mass," the WMO said, citing new data from the Swiss-based World Glacier Monitoring Service (WGMS).
Beyond the continental ice sheets of Greenland and Antarctica, more than 275,000 glaciers worldwide cover approximately 700,000 square kilometres, said the WMO. But they are rapidly shrinking due to climate change.
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Until now, scientists had counted only 220,000 glaciers. "This doesn't mean that new glaciers have appeared, it means that the new inventory is much more detailed," French glaciologist Etienne Berthier told RFI.
A specialist in the spatial analysis of glaciers at the Legos laboratory at the University of Toulouse, he says technology has vastly improved monitoring systems.
"We now have very high-resolution space instruments, on the order of 50 centimetres, which provide much more detail in this inventory of glaciers based on satellite images. We can therefore better see each small glacier, or those that deserve to be separated in two because they have different behaviours," he explained.
According to a study published in the scientific journal Nature on 19 February, approximately 273 billion tonnes of ice melted each year between 2000 and 2023.
This is like emptying "the equivalent of three Olympic-sized swimming pools per second," warned the European Space Agency project Glambie, which authored the study.
Berthier points out that Europe, the fastest-warming continent, lost 39 percent of its glacier volume between 2000 and 2023. In 2021 and 2023 alone, Swiss glaciers lost 10 percent of their mass, the same amount lost between 1960 and 1990.
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"Melting accelerated and became widespread in the 1990s due to anthropogenic greenhouse gas emissions. Each decade, mass losses are greater. In the Alps, it is estimated that between 1 percent and 10 to 15 percent of glacier volume will remain in 2100, depending on the scenario," he explained.
"In the Pyrenees, we have been losing one glacier per year since 2000. Around 10 remain, which are expected to disappear in the next 10 to 15 years," he said.
Based on a compilation of worldwide observations, the WGMS estimates that glaciers – not including the continental ice sheets – have lost more than 9,000 billion tonnes since records began in 1975.
"This is equivalent to a huge ice block of the size of Germany, with a thickness of 25 metres," said WGMS director Michael Zemp.
View of Borebukta Bay, located at the northwestern side of Isfjorden, in Svalbard Archipelago, northern Norway, on 3 May, 2022. AFP - JONATHAN NACKSTRAND
However, the rate of loss is not the same around the globe.
Glacier mass loss was relatively moderate last year in regions such as the Canadian Arctic and the peripheral glaciers of Greenland – while glaciers in Scandinavia, Norway's Svalbard archipelago and North Asia experienced their worst year on record.
At current rates of melting, many glaciers in western Canada and the United States, Scandinavia, central Europe, the Caucasus and New Zealand "will not survive the 21st century," said the WMO.
The agency said that together with ice sheets, glaciers store around 70 percent of the world's freshwater resources, with high mountain regions acting like the world's water towers. If they were to disappear, this would threaten water supplies for millions of people downstream.
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Another issue is rising sea levels, which saw an increase of 1.8 cm between 2000 and 2023.
A rise of at least 30 to 60cm is projected by the end of the century, according to the European Union's observation programme Copernicus, which will affect hundreds of millions of people living in coastal areas.
For the UN, the only possible effective response is to combat global warming by reducing greenhouse gas emissions.
"We can negotiate many things in the end, but we cannot negotiate physical laws like the melting point of ice," said Stefan Uhlenbrook, the WMO's water and cryosphere director.
"Ignoring the problem" of climate change "is maybe convenient for a short period of time," he said, but "that will not help us to get closer to a solution".
However, the rate of loss is not the same around the globe.
Glacier mass loss was relatively moderate last year in regions such as the Canadian Arctic and the peripheral glaciers of Greenland – while glaciers in Scandinavia, Norway's Svalbard archipelago and North Asia experienced their worst year on record.
At current rates of melting, many glaciers in western Canada and the United States, Scandinavia, central Europe, the Caucasus and New Zealand "will not survive the 21st century," said the WMO.
The agency said that together with ice sheets, glaciers store around 70 percent of the world's freshwater resources, with high mountain regions acting like the world's water towers. If they were to disappear, this would threaten water supplies for millions of people downstream.
No chance of saving global glaciers as melt rate goes 'off the charts'
Another issue is rising sea levels, which saw an increase of 1.8 cm between 2000 and 2023.
A rise of at least 30 to 60cm is projected by the end of the century, according to the European Union's observation programme Copernicus, which will affect hundreds of millions of people living in coastal areas.
For the UN, the only possible effective response is to combat global warming by reducing greenhouse gas emissions.
"We can negotiate many things in the end, but we cannot negotiate physical laws like the melting point of ice," said Stefan Uhlenbrook, the WMO's water and cryosphere director.
"Ignoring the problem" of climate change "is maybe convenient for a short period of time," he said, but "that will not help us to get closer to a solution".
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