Famous glacial arch in Patagonia collapses (again)
An ice arch at Los Glaciares National Park in Argentina has collapsed. But, unlike the disappearance of Malta’s famous Azure Window arch last year, there is no cause for dismay.
The arch is formed by a natural process and collapses every two to four years before gradually regenerating once again.
This year, thousands of tourists travelled to Perito Moreno Glacier to witness the spectacle, but were left disappointed when the arch collapsed in a storm overnight.
The Perito Moreno Glacier is a rare growing ice form. Nearly all of the glaciers around the world are retreating, or have disappeared entirely, due to global warming. Pio XI Glacier in Chile and Franz Josef Glacier in New Zealand are two other examples of advancing glaciers.
As the Perito Moreno Glacier grows, its tip cuts off part of Lake Argentino. As a result, the glacier creates a dam and pressure builds in the lake.
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The water pressure creates a tunnel beneath the ice, creating an ice arch through which water can flow. Then, after a certain amount of time, the ice bridge collapses and the process can start again.
There are 47 large glaciers fed by the Southern Patagonian ice field in the Andes, with 200 smaller ones. The UNESCO-protected Perito Moreno is one of Argentina's most popular tourist attractions; many people travel here to get a photograph of one of the blue icebergs being carved off the glacier.
The Perito Moreno ice arch experienced a prolonged period of stability between 1988 and 2004, when it finally collapsed.
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It has come down regularly since. For anyone who fancies catching the spectacle themselves, it'll likely happen next at some point between 2020 and 2022.
