±«Óătv

The regenerators environment topic banner

Welcome to The Regenerators.

Back to top

Introduction

You might love paddling or swimming at the beach. Maybe you love checking out colourful sea anemones in a rock pool.

It could be that you dream of dolphins, splashing around in the deep blue sea. Or maybe you just love fish fingers.

The ocean is beautiful and gives us food and fun. But most important of all, it keeps us alive.

Even if you're miles from the beach, the ocean is always with you. The water you drink and the air you breathe both come to you from the sea.

Back to top

Why are oceans important?

Find out about some to the incredible things that our oceans do to keep our planet healthy.

Back to top

The water cycle

Water on Earth is constantly moving. It is recycled over and over again in a process called the .

The sun heats up water on land, in rivers, lakes and seas and turns it intoan invisible gas called water vapour. This process is called .

The warm water vapour rises high into the sky. Up there, the air is cold and so the vapour begins to cool down again. As it cools, it , which means it turns back into liquid water drops again.

These water drops float around the sky in clouds, blown by the wind. The drops join together to make bigger, heavier drops.

When they get big and heavy enough, they fall back to the earth again as rain. Sometimes, the drops get so cold that they freeze and fall as snow or hail.

A diagram showing the water cycle. water vapour rising from the ocean, condensing to form clouds, wind carrying clouds over land and precipitation falling, before collecting in lakes and rivers, then returned to the sea.

Rain that falls on hills and mountains runs down towards the sea, making streams and rivers. On lower ground, rain fills up lakes, pools and puddles.

Plants soak up the rainwater through their roots, whereas animals and people drink the water.

Most of the rainwater ends up back in the sea. At any moment, 97% of all the water on the earth is in the ocean.

But wherever the rain falls, when the sun comes out from behind the clouds and shines, water vapour begins to evaporate again. It heads back to the sky in an endless journey.

Back to top

Let's go to the beach

Join Liliah and Jayden as they find out from Lauren, a marine biologist, why oceans are important and discover some fun facts about seaweed!

Back to top
Did you know

Did you know?

We breathe in an invisible gas called oxygen from the air around us. And we breathe out an invisible gas called carbon dioxide or COâ‚‚.

On land, trees and other plants take in this COâ‚‚ and give out oxygen again for us to breathe. And in the sea, tiny microsopic organisms, called plankton, do exactly the same thing.

Plankton in the ocean soak up between 20% and 30% of all the COâ‚‚ we make. And they give it back to us as the oxygen we need to live.

Did you know
Back to top

Why our oceans matter

The ocean covers over 70% of the earth’s surface and play an important role in keeping our planet’s temperature and weather in balance. Find out some more reasons why are oceans are important in the slideshow below.

Image gallerySkip image gallerySlide 1 of 3, A blue whale, Life Our oceans are home to an incredible diversity of life. Scientists think there could be more than 2 million species living in their waters, from tiny plankton, which form the foundation of many ocean food chains, to the biggest creature that has ever lived – the blue whale.
Back to top

Changing our oceans

Without the oceans, our planet would be much warmer. Water is really good at storing heat, and there’s lots of water it in the oceans.

As human activity produces more greenhouse gases and the earth’s climate is warming, the oceans are absorbing more heat from the atmosphere. In fact, 90% of the excess heat from global warming is being absorbed by the oceans.

This might sound like a good thing, but warmer oceans come at a big cost for lots of marine ecosystems. Particularly coral reefs, which are very delicate and prone to damage from changing temperatures.

A white coral
Image caption,
Lots of corals depend on a tiny algae that lives inside them to provide them with their food. Warmer ocean temperatures cause the algae to leave the coral, resulting in the coral turning white or very pale.

Our oceans also soak up carbon dioxide from the atmosphere. Again, this might sound like a good thing, because carbon dioxide is a greenhouse gas. However, it’s changing the chemistry of the oceans in a way that is a problem for marine wildlife.

The seawater is becoming more acidic which makes it difficult for sea creatures, such as like plankton, molluscs and coral, to build their shells and skeletons.

Back to top

Lesson complete!

Well done Regenerator, you've completed this lesson. Now let's see what you can remember.

Back to top

Investigation

There is water vapour in the air around us. Here's a simple experiment you can do to prove it.

Image gallerySkip image gallerySlide 1 of 3, Some ice and an empty glass, You will need For this investigation you will need a glass and some ice from the freezer. Remember to ask permission
Back to top

There's more to learn

Explore more lessons and content from around the ±«Óătv.

More from The Regenerators

±«Óătv BITESIZE

More from The Regenerators
Back to top