All About Glaciers
Most people don't get to see them often, but glaciers are one
of the most important features of the natural landscape. About ten
percent of the world's entire landmass is covered in glaciers, and they
store about 75 percent of all the freshwater on Earth! According to
scientific estimates, the world's sea level would rise over 200 feet if
all the glaciers melted. But what are glaciers? How do they form? Where
are they now? The ice sheet in Antarctica alone supplies 70 percent of
all fresh water, so it's important to know what role these mammoth
masses of ice play in the environment.
About Glaciers: Glacier facts and galleries from the National
Snow and Ice Data Center.
Anatomy of a Glacier: From NOVA
Online, a production of PBS.
Glaciers and the Glacier Age: Basic
question-and-answer page on glaciers and the Ice Age. Illustrated.
Glaciers and Ice Sheets: A variety
of information about glacier formation, the polar ice caps, the
Antarctic, and more, provided by the University of Michigan.
The Ice Ages: Detailed explanation
of ice ages, the Earth's climate cycle, and glaciers past and present.
Though glaciers are incredibly big and heavy, they all begin
as piles of mere snowflakes. In a process lasting thousands of years,
glaciers form slowly in areas where the snowfall exceeds any melting
that happens in warm weather. Gradually, the weight of the fallen snow
compresses the whole thing into a mass of ice. Eventually, if the
formation starts on a sloping land mass, the whole thing starts to move
downhill. Glaciers can vary tremendously in size. Almost the entire
surface of Antarctica, 5.4 million square miles, is covered in
glaciers! In the Antarctic region, a single glacier 200 feet high may
be considered "small." In other places, such as Greenland and British
Columbia, glaciers can be the size of a football field or even less.
Glaciers can also be much bigger: the Greenland ice sheet covers over
660,000 square miles. Glaciers vary in shape depending on the terrain
in which they form; they can be tall and high, such as in the
Antarctic, or long and relatively thin, hedged in by mountains to form
a sort of ice river.
Glaciers Online: Includes features
like an interactive map of states with glaciers, glacier photography,
and more information.
Glaciers and Glaciation: More on
glacier movement and the factors that affect the size and shape of
Illustrated Glossary of Alpine Glacial
Landforms: Identifies the different parts of glaciers and
their features. Illustrated.
Virtual Tour: Antarctica: A
photographic virtual tour of a journey to Antarctica, including
information about polar research stations.
Polar Discovery: Thoroughly
illustrated information on polar expeditions and research, including
expeditions focused on evaluating the health of Greenland's glaciers.
The oldest glaciers in Antarctica likely began to form tens of
millions of years ago. Glaciers are mainly found around the world's
polar ice caps, and the Antarctic ice shelf holds 90 percent of the
world's ice. But glaciers are found elsewhere on Earth where polar
conditions prevail. Glaciers are seen around Greenland, Canada, the
Scandinavian countries, Russia, and in the state of Alaska. They can be
found in the sea or high in the peaks of mountains like the Himalayas
and Kilimanjaro. Smaller glaciers are more likely to undergo partial or
complete melting, and they provide the majority of glacial runoff that
enters the ocean annually. In recent years, scientists have become
concerned that larger glaciers may melt due to changes in global
climate. For now, though, researchers believe most of the world's
largest glaciers are far from melting temperatures. Glaciers are hard
for humans to explore, but research stations have been established in
the Arctic, and animals like penguins and polar bears depend on glacial
ice for their habitat.
Glacier Bay: Information and
pictures from the national park in Alaska.
Gift of the Glaciers: On the role
of glaciers in the formation of the Great Lakes.
Glaciers at Risk: Information on
the importance of glaciers from the World Wildlife Foundation.
Glacier National Park: Home to
protected glaciers and stunning examples of natural features carved out
and left behind by glaciers.
All About Antarctica: Information
on wildlife, environment, geography and more in this glacier-heavy
region, provided by the British Antarctic Survey.
Glaciers are a varied, vast, and majestic part of the world's
ecosystem. Though most people may never see a glacier with their own
eyes, there's no denying how important they are. The world's supply of
fresh water depends on the great glaciers, and the features of Earth
bear the imprint of glaciers past and present. By learning more about
them, we can help ensure that out of sight doesn't mean out of mind.
Glacial Geology at the University of
Cincinnati: Includes a stockpile of glacier images.
A Hypertext in Glacial Geology: A
thorough introduction for those interested in the technical details of
Glaciers: Then and Now: An activity
for children to learn about glaciers.
Arctic Circle: Information,
history, culture, and more information about the Arctic Circle, where
many glaciers are found.
Antarctic Animals: Photos and
information on animals that live on and around glaciers.