Global warming is causing most glaciers to melt, but the glaciers in Argentina's Patagonia are known to be uniquely stable. This is because new ice has accumulated as much ice has melted due to warming. However, it has been confirmed that even these glaciers have been melting rapidly over the past five years.
Researchers from Friedrich Alexander University in Germany noted on the 8th that the Perito Moreno Glacier in Argentina, which had thickened for decades, has been rapidly thinning since 2019.
Glaciers are massive ice blocks formed by accumulated snow falling inland, and they were named as such because they move slowly like flowing water. When a glacier flows out and spreads over the sea, it is referred to as an ice shelf.
The researchers confirmed that the Perito Moreno Glacier began to melt rapidly from 2019 by measuring the height of the glacier's surface using satellites. According to the researchers, between 2000 and 2019, the glacier's thickness decreased by 0.34 meters per year. This indicates that there was almost no change. However, from 2019 to 2024, the thickness has decreased by 5.5 meters per year.
Doctoral researcher Moritz Koch warned, "Based on the results analyzed by radar and satellites, a large-scale glacier retreat has already begun, which is irreversible." The exact reason for the rapid melting of the glacier has not been identified.
The reason the Perito Moreno Glacier has remained stable for an extended period despite warming has also been revealed. The researchers explained that the topography of the valley has mitigated the impacts of warming. They stated that the high-elevation areas, where snow accumulates and ice increases, are much larger than the low elevations where ice melts, which is why the glacier has persisted until recently.
The researchers also discovered through computer simulations that the bedrock beneath the glacier supports it, causing it to flow more slowly than other glaciers. However, this situation is expected to change as warming progresses.
The researchers equipped a helicopter with radar and emitted electromagnetic waves to measure the thickness of the glacier. After observing for a year, it was confirmed that the risk of the glacier becoming separated from the bedrock has increased as it melts. They predicted that if the glacier detaches from the bedrock, it would drift into a lake and melt even more quickly.
Bethan Davies, a professor at the Department of Geography at Newcastle University in the UK, told The New York Times, "If the climate cools sufficiently and more snow falls, the Perito Moreno Glacier will grow again as it once did," adding, "To achieve this, countries need to reduce carbon dioxide emissions in the atmosphere to mitigate the effects of global warming."
The results of this research were published in the journal 'Communications Earth & Environment' on that day.
References
Communications Earth & Environment (2025), DOI: https://doi.org/10.1038/s43247-025-02515-7