In October, it happened again. Massive boulders sheared away from the East Buttress of El Capitan and fell thousands of feet to the floor of Yosemite Valley. Nearby climbers were unaffected, but had they or anything else been beneath the rockfall, the results would have been catastrophic.
Rockfall is part of the natural cycle in Yosemite Valley as well as on every mountain on the planet. Many of us have encountered inexplicable rockfall while in the mountains. And many of us have thought, "wow, that thing has been sitting there for millions of years, and it just decided to come down while I was here...how lucky for me..."
While this is a part of life for climbers and for the mountains, it is important to remember that there are over four million visitors to Yosemite National Park every year. And while we are constantly on edge about the possibility of rockfall, your average Hawaiian-shirt-wearing tourist has no idea that there is a danger present. As such, the NPS has hired teams of geologists to study the cycles of rockfall and to try to determine a way to predict it.
As you might think, this isn't the easiest thing in the world to do.
The team the produces Yosemite Nature Notes has put together an engaging episode on rockfall in Yosemite Valley. You can view the video below:
To learn more about rockfall in Yosemite Valley, check out the Yosemite National Park webpage on the topic. To learn more about what industry is doing to protect highways and buildings from natural rockfall, check out the Swiss Federal Institute for Forest, Snow, and Landscape Research and their studies on rockfall here.
Rockfall is part of life in the mountains. And unfortunately also part of what creates injuries and fatalities in the mountains. It's not clear that any scientific research on rockfall could ever be employed by climbers, but it is good to know that there are people out there trying to understand the natural cycles of rockfall...
--Jason D. Martin