The Wonders of Water

The Wonders of Water

By Bryce Baker

Water is a natural resource that makes life on Earth possible. People, animals, and plants cannot live without it. Yet, in many places in the world, people are running low on water to meet their needs. More and more people need larger amounts of water for drinking, energy, farming, and industry. These growing needs influence, or affect, the demand for available fresh water. Also, waste from farming, business, and energy can pollute water in rivers, lakes, and the ocean. Such pollution reduces available water supplies even more. It may seem odd that some people are running low on water because Earth’s surface has more water than anything else. Seventy percent of Earth’s surface is ocean, and oceans hold about 97 percent of Earth’s water. However, ocean water is too salty to be usable. People need fresh water. Fortunately, there is something that turns ocean water into fresh water.

Open Ended

Why can't we just use water from the ocean to drink and water our crops?

Earth’s water is always moving and changing in a circular pattern. This repeating system is called the water cycle. The water cycle plays an important role in providing people with fresh water as a natural resource. The sun provides energy to the water cycle. As the sun heats ocean water, some of the liquid evaporates; that is, it changes into a gas, or vapor. Wind carries the vapor high into the air, where much of it cools and forms clouds. Some of Earth’s water may get stored outside the water cycle. This storage affects how much water is available as a resource. For example, when water freezes in cold weather, it stops taking part in the water cycle. As the weather warms up, the ice melts and returns as water to the cycle. Water is stored for longer periods of time in large ice floes called glaciers and in polar ice. These kinds of ice are not affected much by the seasons. However, in recent decades they have been slowly melting and growing smaller.

Multiple Choice

Earth's water changing and moving in a circular pattern is called what?

• The Water Cycle

• The Moon Cycle

• The Sun Cycle

• Cleaning Water

Multiple Choice

What provides energy to the water cycle?

• Lakes

• The Sun

• The Moon

• Oceans

As the water vapor in the air cools, it condenses; that is, it changes to liquid water, forming tiny drops. These water droplets join with bits of dust, salt, and smoke to form clouds. The wind helps hold clouds in the air and circulates, or moves, them from one place to another. When a cloud has more water than it can hold, water drops fall from the cloud. This water falls to Earth, where it may flow in streams and rivers back to the ocean, providing people with fresh water along the way.

Open Ended

What does it mean for water to "condense"?

Some of the water that falls to Earth is absorbed, or soaked up, by the ground. Some of this water will stay near the surface in the soil. This water may feed plants and trees. In turn, plants and trees give off water vapor from their leaves. However, gravity pulls some of the water deeper below the surface where it fills spaces between rocks and sand. This forms bodies of water in the ground. Ground water may be stored in the Earth for a long time, or it may seep, or leak, into other bodies of water, such as rivers. In many places people drill wells down to the ground water and bring it to the surface for drinking or farming.

Open Ended

How do people get ground water out of the ground?