Satellite images show the extreme impact of global warming on the Alps

A comprehensive study of satellite imagery spanning 38 years – between 1984 and 2021 – has shed light on the immense consequences of climate change on Europe’s beloved Alps.

Not only have the snow caps of these mountains visibly melted over the years, but the range has also rapidly “greened” or grown a shocking amount of vegetation due to factors that are directly correlated to global warming, a phenomenon mainly exacerbated by human activities such as burning coal.

The paper, published Thursday in the journal Scienceincludes the phrase “From white to green” in its title.

As the globe warms and rainfall increases – two consequences of the climate crisis – plants are beginning to colonize areas where they are not really meant to be. Such intrusion leads to denser and taller vegetation in surprising areas, such as the situation with the Alps.

“Alpine plants are adapted to harsh conditions, but they are not very competitive,” said Sabine Rumpf of the University of Basel and lead author of the study. said in a press release. As environmental conditions change, these specialized species lose their edge and become overwhelmed, she added. “The unique biodiversity of the Alps is therefore under considerable pressure.”

You might think that kind of extra greenery seems like a positive thing. After all, vegetation is priceless for planet Earth. Well, that’s not necessarily true. Especially for the Alps.

“Greener mountains reflect less sunlight,” Rumpf said. “And therefore lead to further warming – and, in turn, further shrinkage of reflective snow cover.” In other words, the new overload of alpine greenery could significantly increase the already melted snow content of the Alps.

Nearly 10% of the measured surface experienced a marked loss of snow, highlighted a worrying trend and “for years, local ground measurements have shown a decrease in snow depth at low altitudes”, Grégoire Mariéthoz of the University of Lausanne and co-author of the study, said in a statement.

“This decrease has already made some areas largely snow-free,” added Mariéthoz.

Add to this the fact that the study found that plant biomass – i.e. the weight of living plant matter contained in a unit of ground area – above the predicted alpine treeline has increased in more than 77% of the observed area, and the shape of the problem is brought into focus.

It’s like an endless cycle.

Global warming leads to greening, which leads to melting snow, which leads to warmer conditions, which leads to… greening, and… yeah. But one of these components of the cycle is in the hands of humanity.

Teresa H. Sadler