Glacier article omits one possibility

The Associated Press article about the melting of the glaciers on Greenland ("Mystery of glacier melt gets heated," Sept. 11) does not mention that the ice could be melting from the ground beneath them.

Glaciers move because there is a layer of water between the ice and the ground. Not all of the water comes from the top of the ice, and the increased speed of the ice means that there is more water in this layer.

When ice starts to melt, it melts quickly. At the end of the last great Ice Age, the ice melted quickly and the vast amount of fresh water flowing into the Atlantic from the St. Lawrence River stopped the North Atlantic Circulation for 50 years. Then the circulation restarted. Large lakes formed in inland areas such as eastern Wisconsin that cut the canyon of the lower Fox River from Lake Winnebago to Green Bay when the water topped the Niagara Escarpment.

Lake Bonneville formed in Utah and emptied into the Snake River. A series of large lakes formed on the Upper Columbia River and cut the coulees (dry canyons) in eastern Washington state when they broke though the ices dams that formed them.

Snow cover in states such as Wisconsin melt from both the warmer air above them and the ground warming below them. If deep snows falls before the ground freezes, cars can get stuck in the mud under the snow in the middle of winter. If the ground freezes before any snowfall, the melting in the spring takes longer.

James W. Cleary, Keysville