Rockfall on the Grand Wall in Squamish
Earlier this week a large flake came off the Grand Wall in Squamish. Here's what the Squamish Access Society said about the incident:"Today at around 3pm there was a large rock fall near the Split Pillar pitch of the classic Grand Wall, 5.11. A very large flake about 20m left of the top of the Split Pillar tumbled down the wall directly through the traverse to the bottom of the Pillar, and down the route leading into it, Mercy Me, 5.8. It is likely that the extreme heat of this week was at least a contributing factor. We want to strongly discourage anyone from going to climb any of the routes in the area right now, or hiking up to the base of the wall to check out the damage, especially while this period of intense heat continues. There have been studies on the granite faces in Yosemite that demonstrated a correlation between extreme heat and rockfall there, with increased likelihood during the hottest parts of the day between 12-6pm. This is also a good reminder that all our crags are subject to the risk of rockfall, ranging in size from small to potentially catastrophic."
Curious about the effect of heat on rockfall? Check out this article about studies done in Yosimite National Park.