Rising global temperatures are beginning to have an impact on the Swiss Alps, with their distinctive snow-covered mountains being invaded by plants above the treeline, satellite data reveals.
Scientists describe this phenomenon as ‘greening,’ which is already well documented in the melting glaciers in the Arctic and is now starting to be detected in mountain regions.
Published Thursday in the journal Science, the from the University Basel used high-resolution satellite data from 1984 to 2021 to investigate the change in snow cover and vegetation in the Alps.
Scientists found that the amount of vegetation above the treeline in the Alps has risen by 77 per cent since 1984, but in contrast, snow cover above the treeline has fallen considerably in almost ten per cent of the region (excluding glaciers and places below 1,700 metres).
“The scale of the change has turned out to be absolutely massive in the Alps,†said Sabine Rumpf, lead author of the study and assistant professor at the University of Basel, in a release.
Previous research has mostly focused on the impact of global warming on Alpine biodiversity and changes in plant distribution, but a detailed investigation of plant growth in the Alps wasn’t conducted before.
The study now suggests that rising temperatures leading to prolonged vegetative periods have resulted in an increase in plant biomass.
“Greener mountains reflect less sunlight and therefore lead to further warming – and, in turn, to further shrinkage of reflective snow cover,†said Rumpf.
More plants at high elevations, according to Rumpf, might endanger many native Alpine plants, which are well suited to their harsh circumstances but not competitive. They could be pushed out and “outcompeted†by common species from lower elevations when circumstances become more favourable for development.
“The unique biodiversity of the Alps is therefore under considerable pressure,†said Rumpf.
The consequences of melting snow covers should not be taken lightly, the study notes, and could lead to landslides, rockfalls and mudflows and jeopardize it Swiss Alps' role as a supply of drinking water.