Alpine ice caves on the brink of shrinking, study blames climate change

According to studies, the Alpine ice caves in Austria are getting smaller and smaller due to climate change. Only a small number of the world’s thousands of known ice caves have been thoroughly explored, with Austria boasting one of the highest densities.

Eight ice caves with descending morphology in Styria, Tyrol, Upper Austria and Carinthia have now been thoroughly investigated over the past few years by a team of researchers and scientists from the Universities of Belfast and Innsbruck using a comparative research methodology.

According to Tanguy Racine, individual ice caves have already been the subject of some solid studies. The research, which focused on ice evolution in multiple caves, all in comparable environments – similar elevations and steep to perpendicularly dipping geometry – was the first time a comparative analysis was conducted.

Racine is from the Quaternary Research Group at the Department of Geology. In his dissertation he dealt extensively with the topic. The ice formations in these caves are the result of solid precipitation, particularly snow, which slides into the cave in winter and freezes there when the temperature drops.

Charlotte Honiat and Tanguy Racine from the Institute of Geology collect ice samples from the Tyrolean Guffert ice shaft for laboratory analysis.

ice cave development

The team used the radiocarbon method to determine the age of the layers of ice in the caves, which are often several meters thick. Racine explains the procedure by saying that the research team concentrated on the smallest inclusions of wood samples in the ice layers in order to date the ice. The exact age of these splinters of wood, which fell into the ice caves from the outside, can be precisely determined.

The extensive database of 107 datings of wood samples in the ice gives an accurate picture of ice accumulation and deposition in the ice caves over a longer period up to 2000 years ago.

Using this strategy, the team was able to demonstrate the theory that historically recorded glacial advances, such as those that took place during the “Little Ice Age,” are also reflected in the growth of ice mass in ice caves and occur simultaneously.

A similar ups and downs in ice development can be observed in glaciers and ice caves over the past two thousand years, the geologist continues. How much snow there is in winter and how hot it is in summer is crucial for both. The results also show that a significant portion of Austria’s subterranean ice dates back to the “Little Ice Age” that occurred between the 15th and 19th centuries.

Also Read: Alpine Glacier Collapse Kills Six People in Italy; Snow cover and icy rock slams into the hikers

Shrinking ice caves

Racine notes that glaciers aren’t the only ones showing higher-than-average negative mass balances lately. The balance of the ice caves is also negative. The effects of rising temperatures as well as decreasing precipitation have also had a significant impact on the ice caves.

The study shows a rate of ice retreat that has never been recorded during our 2000-year measurement period. Several examples come to mind: Monitoring in the Guffert Ice Shaft in Steinberg am Rofan between 2019 and 2021 revealed a reduction in the snow surface of almost three meters, and the Eisgruben ice cave near Sarstein in Upper Austria has lost 10 meters of ice thickness in the last 40 years . The Upper Austrian crater shaft in the Sengsen Mountains lost 20 meters of ice during this period.

Similar to the glaciers, this development is due to man-made climate change. Racine clarifies that it can be assumed that the smaller and medium-sized ice caves in particular will drastically lose ice mass or even become completely ice-free in the next few years or decades. The clock is ticking loudly.

In the case of the smaller and medium-sized ice caves in particular, it must be assumed that they will drastically lose ice mass or even become completely ice-free in the next few years or decades. The clock is ticking loudly.

In order to preserve the climate data that is important for science in the long term, the Innsbruck researchers will carefully remove ice cores from Alpine ice caves and store them in a cool place in the coming years, reports Science Daily.

Related article: Rapid melting of alpine permafrost may cause global warming