Indonesia could lose its last glaciers as soon as the next few years

A new study shows: between 1980 and 2024, the glaciers of Puncak Jaya lost about 97 per cent of their area. Of the six glaciers that scientists have taken into account, four have already disappeared completely. Only two remain - the Karstens Glacier and the Eastern Firn of the Northern Wall. They are predicted to be gone by the end of the decade.

This does not mean that Indonesia will be ice-free tomorrow. But the direction is clear: the remaining glaciers are too small, the climate is getting warmer, and El Niño years are accelerating melting. In an unfavourable scenario, the country's last glaciers could disappear before 2030.

Details

Puncak Jaya is located in the Indonesian part of New Guinea. It is one of the few tropical areas in the world where glacial ice has persisted at high altitudes. Such glaciers exist only where the peaks are high enough that the snow does not have time to melt completely.

The scientists studied Landsat satellite images for 44 years - from 1980 to 2024. They used them to track how the area of ice in the Puncak Jaya and Puncak-Idenburg area changed. In 1980, the glaciers covered about 7.46 kilometres². By 2024, only about 0.19 km² remained of them.

By comparison, that's a reduction to near extinction. According to the study, glaciers have lost about 7.28 km² of ice. In 2024, the Karstens Glacier covered about 0.050 km² and the East Firn of the North Face about 0.136 km².

The main reason is climate warming. When temperatures rise, the boundary above which precipitation falls as snow rises. As a result, at the altitude where the glacier used to receive snow and replenish itself, it rains more and more often. Rain does not "feed" the glacier, but on the contrary accelerates its melting.

El Niño years are especially dangerous for these glaciers. In Indonesia, such periods are often associated with drier and warmer weather. Researchers have previously shown that the strong El Niño of 2015-2016 dramatically accelerated the thinning of the Puncak Jaya glaciers: the rate of ice loss increased by about 5.4 times.

There are more recent estimates as well. Gadjah Mada University, citing monitoring by Indonesian agency BMKG, wrote that by the end of 2024, Puncak Jaya's ice cover has shrunk to about 0.11-0.16 km², down from about 0.23 km² in 2022.

Why it matters

The disappearance of Indonesia's glaciers is not just localised climate news. It's a prime example of how quickly small tropical glaciers can disappear. They are particularly vulnerable: their area is small, they are in warm climates, and they are highly dependent on snow falling on the summits.

For science, such glaciers are important as natural archives. Traces of past climates can be preserved in the ice: precipitation composition, dust, chemical markers, signs of past weather fluctuations. When a glacier disappears, this information is also lost.

For local communities, it is also a cultural loss. The ice on Puncak Jaya has long been perceived as something permanent - "eternal snow" in the tropics. Its disappearance shows that climate change is not only affecting the polar regions, but also the mountains near the equator.

Background

Tropical glaciers are not only found in Indonesia. They persist in the high mountains of the Andes, East Africa and New Guinea. But almost everywhere they are rapidly shrinking.

A separate study in the journal The Cryosphere estimated that the area of the Puncak Jaya glaciers has shrunk by more than 99 per cent since 1850 and by about 65 per cent since 2018. According to the paper, they would be about 0.165 km² in 2024, with extinction likely by around 2030.

The story of Punchak Jaya is also important because it is one of the last glacial areas in the tropical Western Pacific. If the remaining glaciers disappear, Indonesia will join the list of countries that have lost all their glaciers.

However, scientists emphasise that even if humanity rapidly reduces greenhouse gas emissions, small glaciers like Indonesia's are already in a highly vulnerable state. A few hot and dry years in a row could be decisive for them.

Source

Francine Hematang et al, "Rapid retreat of tropical glaciers in Puncak Jaya, Papua: Four decades of change observed from Landsat Imagery, 1980-2024", Cold Regions Science and Technology, 2026. The study used Landsat 2-9 satellite imagery from 1980-2024 to track changes in the area of the Puncak Jaya glaciers in Papua. The authors showed that the glaciers lost about 97 per cent of their area in 44 years, from 7.46 km² in 1980 to 0.19 km² in 2024. Of the six glaciers, four have already disappeared, while the remaining two are predicted to melt completely by around 2028-2030.