Climate change

Climate change: The snow-capped Alps are fading fast

science

Climate change: The beautiful snow-capped Alps are vanishing quickly and being replaced by green vegetation, a process known as “greening” that is projected to hasten climate change, according to research released Thursday.

The study, which was published in Science, was based on 38 years of satellite images covering the whole iconic European mountain range. “To be honest, we were extremely startled to observe such a large trend in greening,” first author Sabine Rumpf, an ecologist at the University of Basel, told AFP.

Greening is a well-known phenomenon in the Arctic, but it had not been fully documented on a wide scale in hilly places until recently. Researchers predicted similar impacts since both the poles and mountains are warming faster than the rest of the earth.

To remove agricultural areas from their investigation, the team looked at locations above 1,700 metres above sea level. Forested regions and glaciers were also omitted. Snow cover was no longer present in summer in approximately 10% of the region investigated, according to the data, which spanned the period 1984-2021.

According to Rumpf, satellite photographs can only confirm the presence or absence of snow, but the first consequence of warming is to lower the depth of the snowpack, which cannot be seen from space.

Second, the researchers used wavelength analysis to identify the quantity of chlorophyll present in the flora and discovered that plant growth rose throughout 77% of the zone tested.

Greening occurs in three stages: plants begin to grow in previously uninhabited places, they grow taller and more densely as a result of favourable circumstances, and lastly, certain species that typically exist at lower altitudes migrate to higher elevations.

“These changes are being driven by climate change,” said Rumpf. “Warming implies longer vegetative seasons, more friendly circumstances that encourage plant development, so plants may simply grow more and quicker,” she noted. “The warmer it becomes, the more precipitation falls as rain rather than snow,” says the impact.

And there are a number of negative effects.

Firstly, a considerable portion of drinking water is derived from melting snow. If water is not kept as snow, it evaporates quicker through rivers.

The habitat species that have evolved especially to the alpine environment are thus disturbed. The absence of snow also impacts the tourist sector, which is a major economic engine in the region.

“What we tend to overlook is the emotional side of these processes that the Alps are like a highly iconic symbol and when people think about Switzerland, it’s generally the Alps that they think about,” Rumpf said.

While alpine greening may boost carbon sequestration, the researchers suggest that feedback loops are more likely to result in exacerbated warming and permafrost thawing.

Snow reflects roughly 90% of solar radiation, but plant absorbs considerably more and radiates the energy back as heat, which drives warming, snow melt, and more vegetation: a vicious cycle.