Rising temperatures, presumably due to global warming, have triggered more avalanches in the western Himalayas in the last 50 years than 150 years ago, says a team of European scientists.
When analyzing the climate data hidden in the trees, the researchers found that both the avalanche frequency and their footprint areas increased “significantly” in the Kullu region of Himachal Pradesh and damaged the hills.
Avalanches were recorded in Kullu District for most years in the 1990s, and more than 15 incidents were recorded in the 2000s. The largest occurred in March 2002, March 2003, January 2006 and January 2008.
Archive records show similar trends from the nearby Lahaul, Chamba, and Kinnaur areas – all popular tourist destinations.
Many of these avalanches occurred in late winter (or early spring) and recent observations have seen wet snow deposits dominate, suggesting a significant shift in snow avalanche activity.
“The recent global warming is the most plausible explanation for the drastic increase in process activity,” reported the European researchers in a recent issue of the journal Proceedings of the National Academy of Sciences.
Before the 1970s, snow avalanches were relatively rare. There were hardly any in the 1940s and 1950s. But after the 1970s there was a big leap. In addition, the affected area becomes larger.
The results contradict the intuitive assumption that the warming leads to less snow and thus to fewer snow avalanches.
The discovery has a significant impact on the region, which is facing increasing population and traffic pressures.
“The results are not unexpected, but this study is probably the first to demonstrate what avalanche experts expect in mountainous areas and as a result of climate change,” senior investigator JA Ballesteros Canovas of the University of Geneva told DH.
Canovas and his colleagues from Switzerland, France and Spain reconstructed the climate history of the Kullu region by analyzing the tree rings of 144 trees growing on the slopes.
Because a tree’s growth varies with local weather for a long time, the climate in the forest leaves a long-lasting impression that can be studied later to understand previous climatic patterns.
This is the technique the European team has used to reconstruct avalanche trends in the western Himalayas for the past 150 years.
Has there been a significant increase in avalanches in the last 20 years, which is the warmest in human history? “I can confirm that this increase is being observed at the location we analyzed. However, a full picture of the Himalayas will only come with more study and research, ”Canovas said.