How Does a Glacier Form?

By Alicia Bodine
How Does a Glacier Form?

What conditions are necessary for a glacier to form?

Glaciers can only form in polar regions or high mountains. This is because in those areas summer does get hot enough to melt all of the snow. The glaciers will not be at any more than a 30-degree angle on the bottom. If the snow/ice mixture is at more of an angel than that then it will fall as an avalanche (crumble and separate). A glacier is only considered a glacier after it has begun moving.

How does snow become a glacier?

Snow falls on the flat surfaces, but doesn't melt in the summer. So each year the snow falls on top of the snow from the year before. It also can turn to ice when the snow hits the ground and initially melts a bit. When the snow and ice layers reach a depth of about 150 feet they begin to crystalize. The heavier the glacier becomes year after year, the more likely that gravity will take over and the snow-ice mixture is pulled downward. After that happens it is now categorized as a glacier.

Where do the formed glaciers end up?

The glaciers will slide down mountains and usually end up in either one of two places: a valley or an ocean. The most common places to find these glaciers is in Antarctica, Alaska, Iceland and Greenland.

What kinds of formed glaciers are there?

There are four main types of glaciers: continental, ice caps, piedmont and valley. Continental glaciers are the largest. Because of their size they don't move very fast. They are the glaciers most people think about when they hear the word glacier. Ice caps are the smallest of the glacier family. Piedmont glaciers are a decent size and are seen at the bottom of mountains. Valley glaciers got their start at the top of a high mountain and then fell along the path of an old river to end up in a valley.