Yosemite's largest ice mass is melting fast

The photo on the left of Lyell Glacier in Yosemite National Park was taken by the U.S. Geological Survey in 1883; the one on the right was taken by park geologist Greg Stock in late September.

Climate change is taking a visible toll on Yosemite National Park, where the largest ice mass in the park is in a death spiral. Lyell Glacier has dropped 62% of its mass and lost 120 vertical feet of ice over the last 100 years.

If carbon dioxide levels continue to rise, the earth will eventually become ice-free, according to a study by Ken MacLeod, a professor of geological sciences at the University of Missouri.

Research by scientists at NASA suggests that absorption of sunlight in snow by industrial air pollution including soot, or black carbon, is also causing snow and ice to melt faster.

Yosemite's other glacier, Maclure, is also shrinking, but it remains alive and continues to creep at a rate of about an inch a day.

Future research projects will attempt to use climate shifts chronicled in the widths of tree rings in nearby forests to create computer models that will show the shrinkage of Yosemite's glaciers over the last 300 years — and help predict when they will disappear entirely.

http://www.latimes.com/local/la-me-glaciers-20131002,0,7692754.story