Re: Yosemite Rockfall Year in Review: 2012

2012 was a relatively quiet year for rockfalls in Yosemite. The most consequential event occurred at about 11:00 pm on January 22 above the Big Oak Flat Road. A boulder some 250 cubic meters in volume (about 745 tons) fell from a cliff above the road, slid down the slope below the cliff, and struck the Big Oak Flat Road, punching a hole in the eastbound lane, tearing out some of the retaining wall, and severely damaging nearly 30 m (100 feet) of roadway. The road was closed for about six weeks for repairs.

Consequential rockfalls also occurred from the Church Bowl area, located between Yosemite Village and the Ahwahnee Hotel. On April 3 and 4, two nighttime rockfalls occurred from the cliff directly above the popular climbing route “Bishop’s Terrace”. The area beneath the climb was devastated by rock debris, with dozens of trees snapped or toppled by the impacts. Small rocks tumbled all the way to the Valley Loop Trail. Climbing routes in this area were temporarily closed until the cliff stabilized.

Other areas in Yosemite experiencing rockfalls in 2012 include Mirror Lake, El Capitan, Ahwiyah Point, Half Dome, Glacier Point, Elephant Rock, Washington Column, and Hetch Hetchy.
In all, there were 43 documented rockfalls in 2012, with an approximate cumulative volume of about 700 cubic meters (about 2,100 tons). Both the number of rockfalls and the cumulative volume for all rockfalls in 2012 are substantially less than that documented in recent years. Although it is not clear exactly why rockfall activity was reduced from previous years, it may relate to the exceptionally dry winter of 2011/2012.

That cumulative volume may be down, but it is still a bunch.
Think what Half Dome would look like with a 700 cubic meter
bite taken out of it.

Sounds like a lot but that would be a chunk about 80'X80'X3'. Considering the size of the face of HD....

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Old Dude

My mistake. I was thinking 700 meters x 700 meters x 700 meters.

Ignore me.