The great acceleration reaches new heights

The acceleration of CO₂ emissions in recent decades have caused many indicators, such as socio-economic, meteorological and biological ones, to race. The scientific community calls this phenomenon “the great acceleration”. In a new study, a team of researchers from 11 countries demonstrated that this acceleration is visible today in the most remote reaches of the planet: mountain summits. The scientists brought to light the increasingly rapid colonisation of these summits by lower-level flora.

The study looked at 302 peaks from different mountain ranges in Europe (Alps, Pyrenees, Carpathians, etc.). In 87% of these summits, plants benefited from increasingly mild weather conditions. This migration is also seen in species known for being bad or slow dispersers. The number of plant species colonising European mountain tops between 2007 and 2016 is thought to be five times superior to the amount seen between 1957 and 1966. Researchers also found this trend to be consistent with an increase in temperatures. They noted that other global factors such as nitrogen atmospheric deposition related to pollution, or the presence of humans on mountain summits, do not explain this acceleration.

Until now, no mountain top species has been observed to disappear, but cohabitation may not continue in the long term. Certain plants found on mountain peaks may eventually disappear, unable to migrate to higher altitudes or compete with more competitive lower-level species, leading to the risk of creating an imbalance in mountain ecosystems.