The Water Cycle4th grade ScienceAubrie Broadbent

Purpose

Taken from Utah Science Core Standard One:

Students will understand that water changes state as it moves through the water cycle and be able to explain the

water cycle.

Something to think about…Are you drinking the same water a dinosaur

once drank?Could you be drinking the same water a

saber tooth tiger once lapped up? Or water that a whale once swam in?

Is the water we have on earth today the same water that was here millions of years ago?

YES! There is about the same amount of water on Earth now as there was when dinosaur’s roamed the planet.

ReviewWhat do you remember about the water

cycle?

So what is the water cycle?

Also known as the Hydrologic cycle, the water cycle is the continuous movement of water

on, above and below the surface of the Earth. Water can change states among liquid, vapor

and solid throughout the cycle.

Words to knowPrecipitation: Water moving from the

atmosphere to the surface of the Earth. This can be rain, snow, sleet or hail.

Infiltration: Process by which water on the ground surface enters the soil.

Run off: Movement of land water to the ocean by means of streams, rivers and lakes.

Subsurface flow: The flow of water beneath earth’s surface.

Words to knowEvaporation: When water moves from a

liquid stage to a gas stage.Condensation: The change of water from a

gas stage into liquid water.Transpiration: Process by which plants

return water to the atmosphere.

Parts of the cycle

The JourneyThe cycle starts when the heat from the sun

gives off enough heat energy to evaporate water from the surface of the Earth and into the atmosphere. There in the clouds, the water cools and condenses. When the conditions are right, precipitation occurs and the clouds will drop the water (usually as rain or snow).

The JourneyMost of this water (nearly 80%) will land in the

oceans, but the rest will fall on the land. Streams, rivers and lakes collect water and eventually return it to the ocean to begin the cycle again – this is called run off. Some water will also infiltrate into the ground through subsurface flow will reach the ocean or will be picked up in the roots of plants and return to the atmosphere by means of transpiration.

The Journey

Two DropletsA short story illustrating two water droplets

journey through the water cycle.

Activity: My Life as a DripThis is a creative writing assignment. You will

be writing your own short story as if you were a drop of water. Given a beginning and an end to your story, it will be your responsibility to write the middle action.

It is required that you include at least three steps that can happen to a drop of water in the water cycle from your beginning to your ending.

For example…For example, your story may begin, “Once I

was lying in a puddle in the middle of a parking lot” and end, “And that is how I ended up in this lake.”

You will then talk about your experience as you are evaporated, condensate and travel in the clouds and precipitate into the lake.

Make your story correct, but interesting! This is how you will demonstrate your understanding of the water cycle.

Sourceshttp://earthguide.ucsd.edu/earthguide/diagra

ms/watercycle/

http://sciencenetlinks.com/lessons/the-water-cycle/

http://www.uen.org/core/core.do?courseNum=3040

http://en.wikipedia.org/wiki/File:Water_cycle.png

http://www.epa.gov/safewater/kids/flash/flash_watercycle.html

http://www.pppst.com/clipart.html