Did you know that glaciers have been a steady source of water for more than two billion people globally? Glaciers, snowmelt, and mountain runoff have historically provided a reliable water supply by gradually releasing water during warmer months and accumulating ice during colder seasons.
However, climate change has intensified, disrupting water sources, food supplies, and infrastructure. Glaciers, formed by compacted snow turning into solid ice, flow downhill, melting at lower altitudes or breaking off into chunks upon reaching the sea. Large, continuous glaciated areas are known as ice sheets, with the only remaining ones located in Greenland and Antarctica.
According to a UNESCO report released on March 21, 2025, glaciers play a critical role in water security. More than two million people in Tanzania and Kenya depend on water from Mount Kilimanjaro, some of which is still stored in the mountain’s rapidly shrinking glaciers.
As the world marks the first-ever World Day of Glaciers, it is crucial to acknowledge the staggering loss of over 6,500 billion tons of ice between 2000 and 2023. This amounts to a 20% reduction in ice mass equivalent to supplying the global population with water for the next 30 years.
The past three years have seen the most significant recorded global loss of glacial ice, according to the upcoming State of the Climate 2024 report by the WMO. On average, tropical glaciers have shrunk by 20% since 2000, but the situation in East Africa is even more severe.
The Impact of Glacier Loss in Mountain Regions
According to the World Water Development Report 2025, approximately 1.1 billion people live in mountain regions. While urbanization rates vary, about 34% of the mountain population resides in cities, 31% in towns and semi-dense areas, and 35% in rural regions. The urbanization rate in mountains (66%) is lower than in lowlands (78%) (Ehrlich et al., 2021).
Mountains contribute 60-80% of the world’s freshwater resources, yet they remain among the most fragile ecosystems affected by climate change. Recent data indicates that between 2010 and 2020, global mountain water resources declined by 15%, significantly impacting agricultural and drinking water supplies.
Case Study of Mount Kilimanjaro Glaciers
Recent studies show that the melting of ice on Mount Kilimanjaro and Kenya has been extensive, leading to significant environmental and socio-economic impacts. Mount Kilimanjaro has the largest remaining glacier area in East Africa, covering just under 1 km². Since 1900, the mountain has lost more than 90% of its original glacial coverage.
Scientists predict that Mount Kilimanjaro’s remaining glaciers could vanish by 2040, while Mount Kenya’s could disappear as early as 2030, making them among the first mountain ranges worldwide to lose all their glaciers due to climate change.
Kilimanjaro, a dormant volcano rising 5,985 meters above sea level, has become a symbol of the decline of tropical ice sheets. Research suggests that glaciers are more sensitive to changes in snowfall, cloud cover, and humidity than to minor air temperature fluctuations.
Global heating has triggered shifts in the Indian Ocean’s climate patterns, including tropical cyclones, altering weather conditions around the mountain and accelerating glacial collapse.
Renowned ice climber Will Gadd highlighted the rapid pace of change when he revisited Mount Kilimanjaro in 2020. Comparing it to his 2014 expedition, he observed that some glaciers had shrunk by up to 70% in just six years.
Today, the iconic ‘water tower’ that is Mount Kilimanjaro suffers from the combined pressures of climate disruption, deforestation, and increasing water demand. The melting of its glaciers, which could disappear completely by 2040, combined with increasingly recurrent droughts, threaten the availability of water and the stability of ecosystems in Kenya and Tanzania.
To combat these alarming trends, UNESCO has launched an $8 million initiative aimed at safeguarding water resources and biodiversity in the Kilimanjaro region. The initiative announced by Audrey Azoulay is part of the International Year of Glacier Preservation, led by UNESCO and the WMO. Funded by the Global Environment Facility and executed in partnership with the FAO, it will enhance scientific research and provide direct water access to an additional 100,000 people.
A Look at Mount Kenya Glaciers
Mount Kenya is one of the few African mountains along with Kilimanjaro, Rwenzori, and peaks in Uganda and the Democratic Republic of Congo still possessing tropical glaciers. However, Mount Kenya has the smallest remaining glacier area in East Africa, at just 0.069 km², reflecting a 95% loss since 1900.
The decline has been particularly pronounced since 2016, with the Nothey and Darwin glaciers disappearing and the Lewis Glacier splitting into two between 2014 and 2016.
The Lewis Glacier, once Mount Kenya’s largest, has shrunk by 62% in just five years. Today, the Tyndall Glacier is of comparable size at 0.025 km², though uncertainties remain regarding its lower sections, which may be classified as debris-covered ice.
Glacial melt on Mount Kenya has severely impacted local rivers. Over 66% of residents along the Naromoru River report decreased water flow downstream. Scientific studies confirm these observations, showing that glacier and snowfall contributions significantly influence river levels.
Since groundwater takes approximately 50 years to emerge at the mountain’s base after infiltrating from the glacial zone, the full effects of deglaciation may not yet be visible.
A similar dependence exists on the Ngare Ngare River, where water levels have dropped by 30% in the past decade due to shrinking glaciers. This decline has fueled conflicts among herders and farmers struggling to secure water resources.
The Ngare Ngare River is a vital lifeline for both wildlife and human communities. However, this once-thriving waterway, sourced from Mount Kenya’s glaciers, now faces an existential threat due to glacial retreat.
A Heightened Call to Action
The rapid shrinking of glaciers on Mount Kenya and Kilimanjaro poses a significant threat to water security for millions. These mountain ecosystems, which have provided reliable water sources for centuries, are now under severe stress due to climate change.
Urgent action is required at local, national, and international levels with an urgency for governments and conservation organizations to invest in climate adaptation strategies, sustainable water management, and alternative water sources to mitigate these effects.
Strengthening research, promoting afforestation programs, and improving water conservation techniques are among the measures that can help protect these fragile ecosystems.
As individuals, raising awareness, supporting conservation efforts, and reducing our carbon footprint are steps we can take to combat glacial loss. The fate of these iconic glaciers and in turn fate of the communities that depend on them rests on the actions we partake in today.
