Plants in the Alpine mountain range are starting to sprout an average of six days earlier than 25 years ago, according to a study published in Global Change Biology regarding early thawing.
The research, led by Michael Zehnder from the Institute for Snow and Avalanche Research SLF, reveals that the rapid temperature increase is altering the vegetation growth calendar.
“The ambient temperature after the disappearance of the snow cover is almost two degrees Celsius warmer than 25 years ago,” explains Zehnder in his study.
This phenomenon reduces the time between the end of thawing and the greening of the meadows, affecting biodiversity, the economy, and society.
Impact on biodiversity and alpine agriculture
The early arrival of spring has significant consequences:
- Some species sprout earlier, while others depend on day length and are delayed.
- Changes in the composition of plant communities, with heat-adapted species displacing light-sensitive ones.
- Possible impact on alpine agriculture, which could advance in the future.
According to Zehnder, areas near the tree line (2,000 meters in altitude) depend on warm days to grow, while at higher altitudes there are plants that follow their own cycle.
Monitoring early thawing using artificial intelligence
To analyze these changes, researchers used data from 40 weather stations equipped with ultrasonic sensors that:
- Measure snow depth in winter.
- Detect when plants start to grow in summer, thanks to a machine learning (ML) computational model.
In addition, Zehnder made direct observations in the field, covering areas between 1,700 and 2,700 meters above sea level.
A future of earlier springs
The data shows that the higher areas of the Alps will turn green earlier, affecting ecosystem composition.
“Climate change is transforming mountain ecosystems,” warns Zehnder.
With early thawing and rising temperatures, plant species that respond to heat could displace those that depend on day length, altering alpine biodiversity in the future.
