The water cycle

THE WATER CYCLE

This book is intended to start a conversation about climate change, the Sustainable Development Goals, and how we can work towards meeting the goals. Use it as a launching point with your students towards building a common language around climate action, clean water, sanitation, and how these issues affect their community as well as others around the world.

Written by Jeff Hennigar Photos courtesy of Canva.com Brilliant Labs, 2021

Nothing Stays the Same Earth is always changing. How hot or cold it is, the amount of gases in the air, the number of living things, and the seasons are changing all the time. Sometimes changes to the Earth are bad, but other times it is perfectly normal, or even helpful for things to change.

States of Matter Three of the visible states of matter are solids, liquids, and gases. Imagine putting some ice cubes in a pot on a hot stove. What would happen? As it heats up, the water would melt from solid ice to its liquid state. But then what?

When the water continues to heat up and you'd see some steam leaving the pot. This is water in its gas state. This is called evaporation. As the steam rises higher, it seems to disappear.

The water vapour is still in the air, but it's molecules are spread out enough that we can't see them.

The Water Cycle Just like the water in the pot evaporated into the air, the same thing happens in nature. We call this the water cycle. Water on Earth's surface evaporates into the air and forms clouds. Over time, this water will rain back down to Earth and is collected in ponds, lakes, and oceans again.

What Happens in the Cloud?

Have you ever noticed that when you have a cold drink on a hot day water droplets form on the outside of the glass? This is called condensation, and it is the same things that happen in the clouds that make it rain. The cool and wet air in the clouds is quickly warmed and the water in the air changes to a liquid.

This is also what happens in the sky.

When warm air rises, it causes condensation, and the water droplets fall back to the Earth.

Collecting Water When it rains, snows, or hails, scientists call it precipitation.

Precipitation falls and hills and ditches help guide the water into rivers and streams.

A lot of the runoff water goes back into ponds, lakes, and oceans.

Restart This is where the cycle starts again! Water gathers in ponds, lakes and oceans, and then evaloprates over time back into the air.

The cycle has continued for billions of years! This means the water we drink today may be the same water that the dinosaurs drank over 66 million years ago. This also means the water here now is the same water people will be drinking long into the future!

Lets Review Water gathers on the Earth and evaporates into the sky over time. The water vapour gather as clouds in the sky.

Condensation occurs when water vapour in the air gets heated by warm air. The water falls back down to Earth as precipitation! This runoff flows through rivers, streams, and ground water into ponds, lakes and oceans.

Glossary Condensation: Water which collects as droplets on a cold surface when humid air is in contact with it.

Evaporation: The process of turning from a liquid into a vapour.

Precipitation: Rain, snow, sleet, or hail that falls to the ground.

Runoff: The flow of water occurring on the ground surface when excess rainwater can't soak into the ground.

Inquiry Questions: Where does the water in your community accumulate?

Reach out to experts, or conduct research to find out how water quality is measured and improved in your area.

How is this different from other communities around the country or the world?

Take It Further: Design and build a device to collect or filter water. How could you test the quantity and quality of the water?

Visit projects.brilliantlabs.ca and search for "water sanitization system," or the other projects linked to SDG #7 for more project ideas.

HOW WE CAN HELP TEACHERS & EARLY LEARNERS Brilliant Labs is a not-for-profit, hands-on technology and experiential learning platform based in Atlantic Canada. We support the integration of global citizenship, creativity, innovation, coding, and an entrepreneurial spirit within classrooms and educational curricula.

If you have questions about our organization and how we can help you in your classroom or virtually, please connect with us by email at info@brilliantlabs.ca or visit www.BrilliantLabs.ca