Dear Dr. Universe: What is a glacier? – Addison, Pullman, WA
Dear Addison,
When snow piles up and compresses into a thick mass of ice, we call it a glacier. But a glacier is really more than ice and snow.
“People think of them as these big blocks of ice where nothing could live,” said my friend Scott Hotaling, a biologist at Washington State University. “For a long time that was the idea, that glaciers were devoid of life.”
Hotaling spends a lot of time visiting glaciers, where he’s on the lookout for small, black creatures that live there: ice worms.
Can you imagine living in a giant block of ice? For ice worms, it’s the perfect habitat. Hotaling is curious about how animals and plants have adapted to live in such extreme environments. The ice worm is also a source of food for migrating birds, like the snow buntings and rosy finches, that fly from Alaska to the lower U.S.
Hotaling is also curious about animals that live in the icy water that melts from glaciers. One of these is the threatened meltwater stonefly.
Understanding more about these animal habitats and how they survive can help us protect the species that call glaciers home.
Glaciers are also a source of water for animals and humans.
About ten percent of the land on Earth is covered in glaciers.
Washington state has more glaciers than any other state in the U.S., besides Alaska. In our state, melting glaciers produce 470 billion gallons of water each summer. Humans rely on meltwater for farming, hydropower, and drinking.
“As we use up more and more of the fresh water on Earth, existing sources become increasingly important,” Hotaling said. “Glaciers are the biggest fresh water resource there is.”
If you were to visit a glacier, you might hear quiet trickles of water moving through the ice or a rushing torrent cascading from the end of the glacier. Or perhaps you would hear a loud boom and crack as a piece of ice broke away and became an iceberg.
Glaciers are really heavy and slide down the sides of mountains, carving and shaping different features along the way.
Glaciers in Washington’s Cascade and Olympic Mountains helped sculpt the landscapes we see in Olympic National Park, the North Cascades and even around Mount Rainier.
On the Palouse in eastern Washington, we can also see the history of glaciers. During the last Ice Age, huge floods carried glacial meltwater and pulverized rock, called glacier flour, into the state. When it dried, the very fine dust blew across the land and fell to help form the rolling hills of the Palouse.
A glacier is connected to many parts of life on earth from providing drinking water, to icy habitats, to shaping the environments where we live.
Sincerely,
Dr. Universe
