Welcome to The Regenerators.
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.
Why are oceans important?
Find out about some to the incredible things that our oceans do to keep our planet healthy.
The water cycle
Water on Earth is constantly moving. It is recycled over and over again in a process called the The water cycleThe journey water takes as it moves from the land to the sky and back again..
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 EvaporationThe process by which a liquid changes state and becomes a gas. .
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 CondensationThe process by which a gas changes state and becomes a liquid. , 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.
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.
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!
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 CO鈧.
On land, trees and other plants take in this CO鈧 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 CO鈧 we make. And they give it back to us as the oxygen we need to live.
Why our oceans matter
The ocean covers over 70% of the earth鈥檚 surface and play an important role in keeping our planet鈥檚 temperature and weather in balance. Find out some more reasons why are oceans are important in the slideshow below.
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Changing our oceans
Without the oceans, our planet would be much warmer. Water is really good at storing heat, and there鈥檚 lots of water it in the oceans.
As human activity produces more greenhouse gases and the earth鈥檚 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.
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鈥檚 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.
Lesson complete!
Well done Regenerator, you've completed this lesson. Now let's see what you can remember.
Investigation
There is water vapour in the air around us. Here's a simple experiment you can do to prove it.
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