In the summer of 2022, one of Tyrol's most extensive glaciers experienced its worst mass loss on record. Last year, the Hintereisferner glacier in Tyrol, Austria, reached its glacier loss day (GLD) earlier than ever before.
Views of the Hintresfeyna Glacier on June 23, 2018 (left) and June 23, 2022 (right). 2018 is considered a bad year for glacier mass balance. However, the situation in 2022 will be even worse, because there will be almost no protective snow layer in June.
The Hintereisferner glacier, located deep in Öztel in Tyrol, has been closely observed for more than a century. Its mass balance has been tracked since 1952, making it one of the most extensively studied glaciers in the Alps. For many years it has been the center for glacial and climate research at the University of Innsbruck.
Since 2016, researchers have also used a globally unique system to survey the glacier: a ground-based laser scanner scans the glacier surface every day, returning the altitude changes on the glacier surface.
In this way, the volume changes of the Hinteresfehne Glacier can be monitored in real time. Innsbruck glaciologist Annelies Voordendag led the field measurements at Hintertefner, and the researchers' findings have now been published as a featured article in the journal The Cryosphere.
The terrestrial laser scanner container housing at Hintereisferner in October 2022. Photo credit: EvaFessler
"As early as the early summer of 2022, we have realized that the ice produced by glaciers during the winter will melt very quickly. We call this day 'Glacier Loss Day', or GLD for short. It can be compared with Earth Overshoot Day, which marks the time when we use more natural resources than the Earth can replace in a year."
By monitoring changes in the glacier's volume and mass on a daily basis, the condition of the glacier in a given year can be quickly assessed.
When GLD occurs, it means that the glacier no longer meets the natural conditions of the year. The earlier the GLD occurs, the longer the remainder of the summer and the likely reduction in glacier volume and mass.
The "Ice and Climate" group has been working at the Hinterresferner "Outdoor Laboratory" in Öztal for many years. Image: RainerPrinz
"We used an automated land laser scanning device overlooking the glacier to track the daily volume changes and calculate the day on which the mass gained in winter disappeared. The date for measuring the glacier loss in 2022 is June 23. In the previous two years, the glacier loss day came in mid-August."
Furthermore, in years with negative balance extremes, such as 2003 and 2018, the glacier loss day was not reached until the end of July.
Although every summer in the future may not necessarily look like 2022, glaciologists clearly see the trend because the changes are outside the normal range of fluctuations. "These are clear signs of anthropogenic climate change," adds Rainer Prinz, a glaciologist at the "Ice and Climate" working group in Innsbruck.
The predictions for future development are not optimistic either. "In 10 to 20 years, only half of the Hinteresfenna Glacier will remain. These are clear signs of climate change, the consequences of man-made global warming and our greenhouse gas emissions, which are already affecting us comprehensively today," the team concluded in their study report.