Hydrosphere

What is the Hydrosphere?

The hydrosphere is all the water you can find on, under, and above the Earth. This includes big oceans, rivers, lakes, ice, snow, and even the water in the air! Earth has lots of water—about 71% of its surface is covered by oceans. Most of this water is salty, but a little bit is fresh water that we can drink.

Why is Water Important?

Water is very important for all living things. It helps plants grow, animals drink, and people stay healthy. The Sun and gravity help water move around in something called the water cycle. Water can be in the sky as clouds, rain, or snow. It can also be in oceans, rivers, lakes, or under the ground.

Fun Facts About Water

• Earth is often called the blue planet because so much of it is covered by water.
• It can take many years for water to refill places. For example, lakes can refill in about 17 years, and rivers can refill in just 16 days!
• Only a tiny part—about 2.5%—of all Earth's water is fresh water that we can use.