Tracking The Glaciers

National parks

Vice President Al Gore’s recent speech in front of a Montana glacier was only the tip of the iceberg.

Scientists estimate Glacier Park had about 150 active glaciers in the 1950s. Only 37 named glaciers were tallied during the last comprehensive survey in 1968, excluding some of the smaller remnant glaciers.

A current survey won’t be complete until next year, but scientists expect the number of glaciers to be in the twenties.

Ice under pressure and movement are the two criteria that distinguish a glacier from an ice field or snow field, said Dan Fagre, scientist and global change research coordinator for the U.S. Geological Survey.

“Usually it has to be larger than a tenth of a square kilometer to make the ice plastic and cause it to move,” he said. “What we’re documenting in Glacier Park is a chronic rapid rate of recession.”

The receding glaciers appear to be linked to increases in global temperatures this century, he said. , DataTimes