Earth is often called the Blue Planet because about seventy-one percent of its surface is covered with water. That might sound like a lot, but most of Earth's water is saltwater found in the oceans. Only about three percent of all water on Earth is freshwater, the kind we drink and use for farming. Of that small amount of freshwater, much of it is locked up in glaciers, ice caps, and snow at the poles and on tall mountains.
Water on Earth comes in many different forms and places. Oceans are the largest bodies of saltwater and are found on every continent. Lakes are inland bodies of freshwater surrounded by land. Rivers are flowing bodies of freshwater that carry water from mountains and hills down to lakes and oceans. Underground water, also called groundwater, is water that soaks into the soil and collects in spaces between rocks and sand deep below the surface. Wells and springs bring this water back up to the surface.
All of Earth's water is connected. Water moves from place to place in a never-ending pattern called the water cycle. Water evaporates from oceans and lakes, forms clouds in the sky, falls as rain or snow, flows through rivers, and eventually returns to the ocean. This cycle has been happening for billions of years, and the water you drink today is the same water that dinosaurs drank millions of years ago!
1. Why is Earth called the "Blue Planet"?
2. How much of Earth's water is freshwater?
3. What is groundwater and where is it found?
4. Describe how water moves through the water cycle using at least four steps.
Write a definition or draw a picture for each word.
Sort each water feature into the correct category: saltwater, freshwater, or frozen water.
| Water Feature | Saltwater | Freshwater | Frozen Water |
|---|---|---|---|
| Ocean | |||
| Lake | |||
| River | |||
| Glacier | |||
| Ice cap | |||
| Underground water | |||
| Snow | |||
| Stream |
Draw a simple globe below. Color the oceans blue and the land green. Label at least six water features in the correct places.
Fill in the chart comparing freshwater and saltwater.
| Feature | Freshwater | Saltwater |
|---|---|---|
| Amount on Earth | ||
| Where you find it | ||
| Can humans drink it? | ||
| Examples |
If only three percent of Earth's water is freshwater, why do you think we still need to conserve water? What happens if we waste too much freshwater?
1. About seventy-one percent of Earth's surface is covered with water.
2. Most of Earth's water is freshwater.
3. Glaciers are large masses of frozen freshwater.
4. Groundwater is found deep below the surface of the Earth.
5. Rivers flow from oceans to mountains.
6. The water cycle has been happening for billions of years.
7. Lakes are bodies of saltwater surrounded by ocean.
8. Wells and springs bring groundwater to the surface.
Word Bank: oceanglaciergroundwaterfreshwatersaltwaterwater cyclelakeriver
1. The largest bodies of water on Earth are called ________________.
2. A large mass of moving ice is called a ________________.
3. Water that soaks into soil and collects underground is called ________________.
4. The water we drink is called ________________.
5. Water in the ocean is called ________________ because it contains salt.
6. The never-ending pattern of water moving around Earth is the ________________.
7. A body of freshwater surrounded by land is a ________________.
8. A flowing body of freshwater that moves downhill is a ________________.
Imagine you are a drop of water on Earth. Describe your journey from an ocean to a cloud, then to a river, and back to the ocean. What do you see along the way?