"California law says if you are entering a chain control area, you have to carry chains," said Scott Gediman, a park ranger and a public affairs officer in Yosemite. "Everybody needs to have chains, even if you have four-wheel drive."
Ho, ho, ho, Yosemite: A magical winter destination →
But Gediman said all of the rock falls combined on Wednesday weighed 1,300 tons (1,100 metric tons).
Climber: Rock fall strikes Yosemite for a second day →