On Track For Massive Global Snowpack Loss By 2100 - Physorg

[hatrack]

By the century's end, the Andes in South America will have less than half their current winter snowpack, mountain ranges in Europe and the U.S. West will have lost nearly half of their snow-bound water, and snow on New Zealand's picturesque snowcapped peaks will all but have vanished.

Such is the dramatic forecast from a new, full-century model that offers detail its authors call "an unprecedented picture of climate change." The decline in winter snowpack means less spring and summer runoff from snowmelt. That translates to unprecedented pressure on people worldwide who depend on summertime melting of the winter snowpack for irrigation and drinking water. Hardest hit are mountains in temperate zones where temperatures remain freezing only at increasingly higher elevations, said Steven J. Ghan, staff scientist at the Department of Energy's Pacific Northwest National Laboratory and lead author of a study describing the model in the current Journal of Climate. PNNL scientist Timothy Shippert was co-author.

Alaska in 2100 will maintain but 64 percent of its year 2000 snowpack. In Europe, the Alps will be at 61 percent and Scandinavia 56 percent. The Sierras, Cascades and southern Rockies will be at 57 percent of current levels. The Andes will drop to 45. And Mt. Cook and its snowcapped neighbors in New Zealand will be much less scenic at 16 percent of current.

Ghan said the model, which actually simulated years 1977 to 2100 to use known data as calibration, differs from past attempts because it generates snow information for small areas – 5 kilometer grids, or about 3-miles – on mountains ranges over such a long period. "Global climate models have never been run at 5 kilometers resolution for a period covering more than a couple of months," Ghan said, "even on the biggest computers in the world."

EDIT

http://www.physorg.com/news67182402.html

[NNadir]

1. That sounds overly optimistic.

I'll bet it's worse than that.