The largest glacier in the Alps is disappearing before our eyes13 Sep 2019 futurasciences
The impressive Aletsch Glacier, the largest glacier in the Alps, located in Switzerland in the canton of Valais, could completely disappear by the end of this century if nothing is done to curb global warming, warned Swiss researchers on Thursday. They carried out simulations using advanced techniques to highlight the upheavals that the glacier, with an area of 86 km2 and whose mass is estimated at 11 billion tonnes of ice, will undergo, if global warming persists, explained in a press release the Swiss Federal Institute of Technology Zurich (ETH).
Middle part of the glacier with Konkordiaplatz at the bottom,
Some very dismal scenarios
The tongue of the glacier has receded about a kilometer since the turn of the century. Scientists predict that this melting will continue even if the world is able to fulfill the objectives of the Paris climate agreement of 2015 aimed at containing below 2 degrees of global warming compared to pre-industrial levels. Researchers at the Swiss Federal Institute of Technology in Zurich say that even under the most optimistic scenario, the glacier could lose 50% of its volume and length by 2100, while in the worst case, there will be only "two shabby patches of ice" left.
In a previous study, researchers at this university establishment had determined that 90% of the 4.000 or so glaciers in the Alps would have disappeared by 2100 if nothing was done to reduce greenhouse gas emissions. The study released Thursday deals specifically with the Aletsch Glacier. Guillaume Jouvet and Matthias Huss, from the School's hydraulics, hydrology and glaciology laboratory, performed 3D simulations that show the retreat of the glacier according to different scenarios of global warming established for Switzerland.
Inexorable melting even with a stabilized climate
Their 3D models show the dramatic shrinkage of the glacier seen from the peaks of the Eggishorn (2.927 meters above sea level) and the Jungfraujoch (3.466 m) over the next eight decades. The researchers based themselves on three scenarios determined by different concentrations of CO2 in the atmosphere.
Even if the warming is contained below two degrees and the climate stabilized by 2040, it must be assumed that the Aletsch glacier will continue to retreat until the end of the century, said Mr. Jouvet, recalling that the great glaciers react late to climate change.
This means that both "the volume and the length will be reduced by more than half compared to today". But, if in Switzerland, the temperature increases by four to eight degrees by 2100, "an unfavorable scenario but unfortunately perfectly realistic," he added. Only two "miserable patches of ice" will remain. The Konkordiaplatz (see photo above), a vast expanse still covered with a thickness of 800 meters of ice located just behind the Jungfraujoch, will be completely devoid of it, warned Guillaume Jouvet.