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291

water

OLogy Series
geology
card
291

water

OLogy Series
geology

There is nothing in the world like water. Without it, our world would be a very different place. Water covers over two-thirds of Earth and makes all life possible. It shapes our planet's surface, carving canyons and moving continents. It works with the Sun's energy to control our climate. And it is essential to our survival, as well as for food, transportation, sanitation, and even power. We need to conserve and protect this precious resource.

All water on Earth is linked in a water cycle. As it moves between the atmosphere, land, and sea, it changes state. As a cloud, water is a:

solid

liquid

gas

Are you right?

Correct!

Clouds, fog, and mist are clusters of tiny liquid water droplets called "drizzle drops." Each drop is smaller than a tenth the width of a human hair.

The oceans hold over 97% of Earth's water. The remaining 3% is fresh water. Most of Earth's fresh water is found:

underground

in lakes, rivers, and swamps

in glaciers and ice caps

Are you right?

Correct!

About 69% is frozen in glaciers and ice caps, 30% is groundwater, and only 0.3% is in rivers, swamps, and lakes.

Ensuring that everyone on Earth has enough fresh water will be one of the major issues facing us this century.

To tackle the problem of water shortages, the focus should be on conservation--how to live with less water.

All animals drink water.

Fact
or
Fiction
?

Fiction

All living things need water to survive, but not all species drink it. In fact, some animals like kangaroo rats get all the water they need from the food they eat.

The more it rains and snows, the more water Earth has.

Fact
or
Fiction
?

Fiction

The total amount of water on Earth never changes. The same amount of water might change state (between liquid, solid, and gas), or change location (from the ground to the air).

Definition: an odorless, tasteless substance that is essential for all plant and animal life
Chemical formula: H2O (two hydrogen atoms bonded with a single oxygen atom)
States: solid (ice), liquid (water droplets), and gas (water vapor)
Climate: Ocean currents and sea ice play a key role in regulating Earth's climate.
Cool fact: Water is found in all living things. Two-thirds of the human body is made of water.

Image credits: courtesty of AMNH / C. Chesek; Eleanor Sterling: courtesy of AMNH; Eleanor Sterling: courtesy of AMNH.