Climate Connections - Glaciers
With less unity and more division in the world’s response to climate change, we aim to take a forward look at some of the issues where the world may in due course conclude that it is worth acting together once again.
The first article in this series considered Heatwaves and Extreme Weather. In this second article in our mini-series, we consider the impact of climate change on the world’s glaciers. It comes as the United Nations has declared 2025 to be the International Year of Glaciers’ Preservation.
In our series we continue to investigate some of the impacts of climate change that are having a worldwide impact, and which may therefore have the potential to generate a worldwide response.
We argue that climate change is not a series of isolated events that can make us pause for a moment, regret the effects on some distant spot on the globe, and then move on. Rather it is a worldwide and connected phenomenon, we are all unwitting participants, and we might as well all start asking how we can contribute to solutions.
A glacier in retreat in Patagonia
IPCC Special Report On Oceans And Cryosphere In A Changing Climate
In 2019, the Intergovernmental Panel on Climate Change, ‘IPCC’ released a Special Report on Oceans and Cryosphere in a Changing Climate. It had a separate chapter on High Mountain Areas. This summed up the current state of scientific knowledge of a majority of the world’s climate scientists, and their consensus that:
Most glaciers are shrinking;
The Greenland and Antarctic ice sheets are losing mass;
Sea ice extent in the Arctic is decreasing;
Northern Hemisphere snow cover is decreasing; and
Permafrost temperatures are increasing.
What is the Cryosphere?
The cryosphere refers to the parts of Earth's surface where water is in solid form, including snow, ice, glaciers, ice sheets, and permafrost.
The IPCC report was clear. There has been a general decline in low-elevation snow cover, glaciers and permafrost in recent decades due to climate change.
This applies to the Canadian and Russian Arctic, Svalbard, Greenland and Antarctica, the southern Andes, Caucasus and European Alps/Pyrenees. Exposure of people and infrastructure to natural hazards has increased. Species composition and abundance in high mountain ecosystems has been heavily affected. Snow runoff in glacier-fed river basins has been affected.
Snow cover, glaciers and permafrost are projected to continue to decline in almost all regions throughout the 21st century.
River runoff in snow dominated and glacier-fed river basins will change further in amount and seasonality in response to projected snow cover and glacier decline with negative impacts on agriculture, hydropower and water quality in some regions.
Current trends in cryosphere-related changes in high mountain ecosystems are expected to continue and impacts to intensify. That, in summary, was what scientists told us to expect in 2019: the scientific consensus was updated in 2025.
UNESCO Report 2025
In 2025 UNESCO produced The United National World Water Development Report 2025, Mountains, Glaciers, Water Towers.
This report revealed that the Andes, which supply 50% of the water flowing into the Amazon River, have lost between 30% and 50% of their glaciers since the 1980s. It projects that the Mount Kenya, Ruwenzori and Kilimanjaro glaciers will have disappeared by 2040 if no action is taken, while the ‘Third Pole’, also known as the Hindu-Kush-Karakoram-Himalayan system, could lose 50% of its glacier volume by the year 2100. The report noted, for example, that China’s glacier area has already shrunk by 26% since 1960, with 7,000 smaller glaciers disappearing altogether.
Similar points are regularly made by the work of the International Centre for Integrated Mountain Development, ‘ICIMOD’.
A photo of Passu Glacier, Gilgit-Baltistan - with evidence of recent retreat. Taken by William Wilson in 2024.
Blatten and the Birch Glacier: 28th May 2025
Blatten was a picture postcard Swiss village: chalet houses, a church, the Edelweiss Hotel. And then on 28 May 2025 the Birch glacier in the mountain above the village collapsed, bringing down part of the mountain with it. Mercifully the Swiss authorities had sufficient warning to have evacuated the village, although one person is still missing. Switzerland had the skills and resources to apply the best available early warning system: other countries may not be so fortunate.
The BBC report of 31 May 2025 by Imogen Foulkes and the Visual Journalism team is really quite unforgettable, and it is hard to add anything to the images that it contains.
Aftermath of the collapse on 30 May 2025. By Federal Office of Topography swisstopo – Rapid Mapping - Swisstopo / map.geo.admin.ch / Rapid mapping, Attribution-Swisstopo, https://commons.wikimedia.org/w/index.php?curid=166532775
Pakistan
In 2022, Pakistan suffered the worst floods in its country’s history, with a third of the country under water. They came about after torrential monsoon rains followed a particularly scorching summer heatwave, but they were accentuated by already high river levels due to glacial meltwater from Pakistan’s 7,200 glaciers.
Our film on Climate Carnage in Pakistan, which was shown in the margins of the COP27 climate talks in Sharm El Sheikh, Egypt, recorded the impacts of this combination of extreme weather events due to human-induced climate change on 33 million people.
The Royal Geographical Society has produced resources for schools studying these impacts, and point out that post-monsoon rainfall in Sindh that year was 508% above average.
Glacial runoff irrigation in the Hunza Valley. William Wilson
Apart from local risks of glacial lake outburst floods, the long term risks to the water supplies of the Indus and Ganges river systems alone could affect one billion people, and 130 million downstream farmers, as a study from the Grantham Institute on Climate Change and the Environment noted in 2019.
The Hunza Valley in Gligit-Baltistan, northern Pakistan, is a series of rocky desert valleys between the snow capped peaks of the Karakoram. The Mirs of Hunza used to preside over their length of the Silk Road from Altit Fort. Centuries of brilliant farming and agriculture have developed rocky terraces in which tall poplar tress shade the apricots and walnuts and apples for which Hunza is famous. But all of it is fed by a complex of channels of glacial runoff. If that should dry up, as science tells us that it will, they will need other ways to collect winter rain and snowfall, or this miraculous valley will return to the desert from whence it came.
Canada
Canada has marked the International Year of Glaciers’ Preservation with a report recording photographic evidence of glaciers accelerated retreat in the Canadia Rockies and the Canadian Arctic. The report also notes the impact of methane emissions released from melting permafrost, and the way in which the process can be accelerated when soot from wildfires forms a dark surface on glacial ice, absorbing more heat from the sun.
Glaciers in North America
NASA is not encouraged by the current U.S. administration to take much of an interest in climate change. But before that happened it has been one of the foremost authorities on earth observation and produced some of the clearest evidence of glacial retreat such as this article and phot-montages from the Cascade Mountains in Oregon, USA.
Glaciers in South America
The impact of human-induced climate change on glaciers in other continents was sharply illustrated by the long battle by the Peruvian farmer and mountain guide Saul Luciano Lliuya to show in a German court how the German utility RWE had contributed a measurable amount to global climate change, and should therefore assume a measurable proportion of the cost of averting the risks of a glacial lake outburst flood affecting his home, and the town of Huaraz in the high Peruvian Andes. Sr Lliuya eventually lost his ‘David against Goliath’ fight in the German court, but on the facts – the court could not accept the stated likelihood of a catastrophic flood despite earlier instances. Sr Lliuya’s case has moved the dial on future litigation based on advancing attribution science.
We have reported on the case here.
Arctic: Greenpeace Images
In 2024, Greenpeace published a series of photographic comparisons of Arctic glaciers as they used to be and as they are now. Again the photographic evidence is clear and unarguable, and should be taken with the evidence of diminishing sea ice.
Antartica
In 2023, satellite observations and international teams of scientists in Antarctica noted the rapidly melting glaciers in that continent, and the effects of warming sea temperatures in accelerating that process.
Russia and the Caucasus
The United Nations Environment Programme ‘UNEP’ produced a second report on the Caucasus Environmental Outlook (CEO – 2) ahead of the COP29 climate talks in 2024 .
This documents glacial retreat in Armenia, Azerbaijan, Georgia, Iran, the Russian Federation and Türkiye, and the predicted impact of this on drinking water, predicting a 20% loss of river flow by 2100.
What can we do?
We could start by recognising that what is happening to the world’s glaciers is definitive evidence of the worldwide impacts of human-induced climate change, which is absolutely not confined to impacts on one region at a time.
21st March 2025 was designated by the United Nations as the World Day for Glaciers. UNESCO produced a short film of Explorer Mathieu Tordeur in conversation with Glaciologist Heïdi Sevestre. They had interesting ideas about how the issues need the science, but also the explorers, the communicators, the politicians, the local communities, to engage a wider public in the debates and the solutions.