The guidebook Arnaud Temme and his friends used on a 2011 climb in the Swiss Alps didn’t mention any dangers on the route. But the group struggled through loose and falling rock, including one that landed on Temme’s helmet. He wasn’t hurt, but back at his lodging that night, he looked at a newer guidebook that warned of rockfalls on the trail.
The inconsistency led Temme, a geomorphologist at Wageningen University in the Netherlands and an affiliate of the Institute of Arctic and Alpine Research at the University of Colorado Boulder, to study trail descriptions in guidebooks dating back to the 1800s. The newer the book, he found, the more warnings about rockfalls on trails--a discovery that correlated with warming temperatures worldwide.
After three years of research, Temme concluded that climate change poses increasing dangers for mountain climbers in the area of the Swiss Alps that he studied. Because many of the same climate effects occur in Colorado, he says, it’s likely that rockfalls are increasing here, too.
Temme recently spoke to Outside magazine about his findings. He also spoke with Colorado Matters host Andrea Dukakis.