The glaciers of the Dolomites are disappearing
It’s not just about the iconic Marmolada Glacier in the Dolomites. In the coming decades, the other glaciers in this mountain range could also shrink dramatically or vanish altogether. This theory is supported for the first time by a study conducted by the Institute of Polar Sciences of the Italian National Research Council (Cnr-Isp), based at Area Science Park, and the Ca’ Foscari University of Venice, recently published in the journal The Cryosphere. The Italian Glaciological Committee, the Alpine-Adriatic Meteorological Society, ARPA Veneto, the Geological Survey of Denmark and Greenland, the Technical University of Denmark, the Roma Tre University in Rome and the University of Quebec in Montreal all collaborated in the study.
“The Dolomites have been the subject of numerous studies in the fields of geology, geomorphology and biodiversity. However, the glaciers in this region have often remained on the margins of scientific investigation, with the exception of the Marmolada Glacier, the largest in the area”, explains Renato R. Colucci, a researcher at Cnr-Isp and co-author of the paper. “Regardless of the information provided by the two editions of the Italian glacier registers (1962 and 2015), the data available on their evolution over time have so far been extremely fragmented and have often only been qualitative, especially regarding their variations in volume. Our study is the first to present a multi-decade estimate (from the 1980s to 2023) of topographic changes and mass balance of the current mountain glaciers in the Dolomites”.
The result was achieved in two steps: for the period from the 1980s to 2010, researchers used the Structure from Motion (SfM) technique applied to historical aerial imagery; from 2010 to 2023, they also used drone (UAV) imagery and helicopter-based LiDAR (Light Detection and Ranging) acquisitions, which allowed for high-resolution and accuracy.
In 2023 – the last year examined in the study – there were 9 glaciers, although the fragmentation of the Marmolada Glacier into four distinct glacial bodies brings the total number to 12. “The total area of these last 12 glaciers has decreased from just over 4 square km in the 1980s to just under 2 square km today – a 56% loss, of which 33% has occurred since 2010,” specifies Andrea Securo, PhD student at the Ca’ Foscari University of Venice and co-author of the study. “Overall, we observed an average decrease in the topographic surface of the glaciers of 28,7 metres between 1980 and 2023 – of which 33% between 2010 and 2023. The glacier that suffered the greatest reduction was the Fradusta Glacier, which underwent a decrease in average thickness of 50 metres and an areal reduction of 90%.”
The temperature data processed for the study in collaboration with ARPA Veneto is also interesting, showing a rise of +2.0°C over the past 40 years – approximately +0.5°C per decade. At the same time, the data also shows a certain increase in snowfall, but only at high altitudes. The researchers warn that this phenomenon was not enough to compensate for the greater melting caused by increasingly long and always hotter summers.
In conclusion, the study highlights that, in the entire area, 66% of the total volume loss is attributable to the Marmolada Glacier alone. “Today, the Dolomite Glacier accumulation areas lie below the alpine glacier equilibrium line, an indicator of the fact that, within a few decades, these glaciers will either disappear completely or become fragmented glacial bodies with no dynamic activity. Unfortunately, their fate appears inevitable, even assuming climate stabilisation based on the average values of the past 30 years (1991–2020),” the authors conclude.
Source: CNR (Italian National Research Council)