Skiers in the Alps could enjoy only half the number of days of snow cover by the end of the century as a result of higher temperatures if greenhouse gas emissions remain at high levels, according to a study published today in the journal Hydrology and Earth Sciences.
Such a sharp reduction in the number of ‘snow days’ would have a significant impact on water availability, nature, and the winter sports industry, the researchers warned. But they also stressed that with climate action to slash emissions, an estimated 83 per cent of current snow days could be saved by the end of the century.
The paper’s projections indicate that without rapid emissions cuts, the loss of snow would be particularly severe in the southern Alps in Italy, Slovenia, and parts of France, with the south-west Alps likely to be especially badly hit.
Lead author of the study Dr Michael Matiu, from Eurac Research in Italy, said: “I expected reductions in snow cover, but the changes found by this paper under a strong warming scenario – of 4C to 5C – are very high. On the other hand, there is a large margin of potential savings, if warming is limited within the Paris Agreement – which raises hope.”
Warming in excess of 4C is now thought to be unlikely this century, given the growing competitiveness of clean technologies and governments’ commitments to slashing emissions in line with the goals of the Paris Agreement. However, environmental campaigners have warned that such potentially catastrophic levels of warming cannot be ruling out given global emissions are still, and that even at lower levels of warming significant climate impacts will still be unleashed.
While winter sports fans would be hard hit by the projected decline in snow days, the loss of snow cover would have much more serious implications for areas downstream that rely on the annual spring and summer snow melt for water.
“Snow loss will lead to a temporal shift in water availability, with higher water flows in winter and less in summer,” said Matiu. “This is particularly challenging in areas which are already fighting for water usage. In any case, the Alps – or the countries and regions sharing the Alps – will need to find a way to manage water availability… to have enough water for agriculture, energy production , domestic use, tourism, at the right time and in the right location.”
The study also found that the number of snow days lost would vary with altitude. Mountains at 2,500 metres, for example, would lose 76 days – almost three months of snow per year – if emissions remain high. If emissions are cut in line with the Paris Agreement, and global warming is constrained to 1.5-2C, just 26 days – less than one month – would be lost. At 500 metres, snow days could be almost quartered. Around 14 days would be lost if emissions are high, leaving just five days of snow per year, but cutting emissions could save ten snow days.
Dr. Martina Barandun, a glaciologist at EURAC Italy who was not involved in this study, said: “Changing snow cover patterns will affect the timing and amount of water released and affect irrigation practices… Coming from a farming background, I know the immense stress and pressure this exerts on the small farmers in mountain regions.”
While skiing would potentially be able to continue in places thanks to snow-making machines, Matiu said that ski resorts would have to defend their high energy and water usage “especially in times of water scarcity”.
The warming temperatures in the mountains would also threaten the Alps’ biodiversity, including Alpine flowers, ibex and marmots, the scientists said.