How Does the Water Cycle Work?

Lesson Plan - Get It!

Audio:

Your typical day may include breakfast in the kitchen, school time, and some play time outside.

Each day in the life of a water molecule is different. Water is recycled daily, constantly moving through the atmosphere and along the surface of the earth. This process is called the water cycle.

If you missed, or would like to review, the first lesson in The Hydrosphere, find it in the right-hand sidebar under Related Lessons.

The water cycle has a couple of different processes that you might be unfamiliar with, and some that you know all too well!

Precipitation happens when water falls from clouds to the surface of the earth. It can be in solid or liquid form, as either snow, sleet, or rain.

Once the water reaches the ground, it can become runoff and travel into bodies of water, or it can drip into the soil and become groundwater.

When rain water falls and moves along the surface of the earth, it picks up chemicals and other materials along the way as it flows into bodies of water. Runoff from rain can be pretty dirty.

Groundwater accumulates over a long period of time as more water moves down through the soil and is stored. The process of water moving downward is called percolation.

As water moves down through the soil, chemicals and toxins are removed, and that makes groundwater clean and safe to drink.

Water that is stored above ground can evaporate. During evaporation, water moves from a liquid state to a gas. The gas can then move up into the atmosphere and become part of a cloud.

Water vapor in the atmosphere can condense into clouds when the temperature drops. This is the same process as when a cold drink gets water on the outside of the glass.

When the cloud warms back up, the water vapor can fall back to the ground as precipitation.

Water stored in the ground can move into plants through the roots in the soil.

Plants release water through a process called transpiration, when water is released from the plant as a waste product. This water moves back into the atmosphere and continues the water cycle process.

The water cycle moves water through the atmosphere, ground, and bodies of water. Water molecules continue to cycle through each phase of the water cycle over and over again, constantly being recycled.

Water falls to the surface through precipitation, where it either runs off into a body of water or into the ground. Water can evaporate or move through the process of transpiration using plants.

Create a quick diagram to show the phases of the water cycle as you understand them. Then, move on to the Got It? section, where you will review vocabulary words involved with the water cycle.