The changes that have been advancing in space for almost 38 years are now clearly visible from space Alpsmaking them increasingly poor in snow And rich in greenwith the vegetation that rises higher and higher: the American satellites have recorded them Landsat for the observation of the Earth, indicating how some areas that are beyond the so-called ‘tree line’, that is the border beyond which vegetation is depleted at high altitudes, begin to color green. Research is analyzing satellite images and data to photograph the health of the largest mountain range in Europe published in the journal Science from the Swiss universities of Basel and Lausanne, in collaboration with researchers from the Netherlands and Finland.
Previous studies had indicated some effects of climate change on the Alps, but never before has such a detailed analysis of changes in Alpine vegetation been conducted. Landsat satellites, owned by NASA and the US Geological Service (Usgs), have recorded the changes that have taken place between 1984 and 2021 and the researchers’ conclusion is that, as is happening in the Arctic, the Alps are also becoming increasingly green.
Although the reduction of the snow cover is now clearly visible from space, this is only one of the problems of this unique area, observes Sabine Rumpf, of the University of Basel, who conducted the research with Grégoire Mariéthoz and Antoine Guisan, both of the University of Lausanne. The problem is in fact a sort of chain reaction triggered in areas where snow cover has decreased significantly, although these represent less than 10% of the area, for researchers they indicate a worrying trend.
There tree line yes it is indeed moved up in about 77% of the Alps and the fear is that in the future moving further, accelerating the melting of snow: this would alter the albedo, that is the extension of the areas that reflect the sun’s rays, and this phenomenon could in turn cause the melting of the frozen ground, the permafrostand destroy the habitat which currently house animals and plants typical of the Alpine area and with reflections that could also affect the economy of this area, starting with tourism.
“The extent of the change has been absolutely enormous in the Alps,” notes Rumpf. The Alps are becoming greener as plants are colonizing new areas and vegetation generally becomes denser and taller: a phenomenon mainly due to variations in rainfall and longer vegetation periods due to rising temperatures. ‘Alpine plants are adapted to difficult conditions, but they are not very competitive,’ continues the researcher; that is to say that, as environmental conditions change, current species lose their advantage. Consequently, Rumpf notes, “the biodiversity only one of the Alps is therefore subjected to considerable pressure “.