Switzerland’s glaciers melted by half in less than a century, study finds | Science & Technology News
One study has shown that Switzerland’s 1,400 glaciers have lost half of their total volume in less than a century, and ice retreat is increasing.
According to researchers from ETH Zurich and the Swiss Federal Institute for Landscape, Snow and Forest Research, the volume of ice halved in the 85 years between 1931 and 2016.
Since 2016, they have lost another 12%.
“The retreat on glaciers is accelerating,” said Daniel Farinotti, co-author of the study published in the scientific journal The Cryosphere.
“Closely observing this phenomenon and quantifying its historical dimensions is important because it allows us to infer the response of glaciers to climate change.”
By area, Switzerland’s glaciers account for about half of the total in the Alps.
In the first reconstruction of lost ice in Switzerland in the 20th century, based in part on an analysis of changes in the topography of glaciers since 1931, the teams combined long-term observations of the glacier. , field measurements and aerial and mountaintop photographs.
Those photos include 22,000 photos taken from the mountain peaks between the two world wars.
By using multiple sources, the researchers were able to fill in the gap, as only a few of Switzerland’s glaciers have been studied regularly over the years.
Their research involved the use of decades-old techniques to enable the comparison of the shape and position of terrain images as well as the use of cameras and instruments to measure the angles of land areas. .
Fieschergletscher Glacier in 1928. Photo: swisstopo and VAW / ETH Zurich
Fieschergletscher Glacier in 2021. Photo: swisstopo and VAW / ETH Zurich
The team compared the surface topography of glaciers at different times, allowing for calculations of the evolution of ice mass.
They found that not all glaciers are losing ice at the same rate.
Altitude, the amount of debris on the glacier, and the flatness of the glacier’s “snout” – the lowest, most melting part – were all found to affect the rate of retreat.
They also found two periods, the 1920s and 1980s, that experienced sporadic growth in glacier mass – although that was overshadowed by a broader trend of decline.
