What causes ocean acidification?

carbon dioxide dissolving in sea water. More carbon dioxide in the air means more in the sea.

Why does the melting of ice sheets raise sea level?

water that was stored on land flows into the sea. Ice on land adds new water to the ocean.

ground that stays frozen all year. Global warming is melting it.

Why might pests spread to new areas as the climate warms?

warmer conditions let them survive where they could not before. Cold winters used to kill them off.

Which is an impact of climate change on people?

forced migration. People leave flooded or drought-hit land.

Why does a warmer ocean take up more space, even with no extra water added?

water expands when it is heated. This expansion is one cause of the rise in sea level.

Impacts of climate change · Cambridge IGCSE Environmental Management

In plain words

A degree or two sounds small. Spread over a whole planet, it is enough to melt ice sheets, move rain belts and push species off the top of mountains. The impacts are a chain, and the exam rewards following it link by link.

8 things to know

The temperature of the Earth's surface rises, and so does the temperature of the ocean surface.
Ice sheets, glaciers and permafrost melt, and sea water expands as it warms. Sea level rises, and low-lying land is flooded and lost.
Ocean acidification: with more carbon dioxide in the atmosphere, more dissolves in the sea, which makes the water more acidic. Corals and animals with shells suffer.
Extreme weather events become more frequent and more severe. This brings flooding and loss of land, drought and wildfires.
Habitats are lost as conditions change. Species that cannot move or adapt die out, so biodiversity changes, and food chains are disrupted.
Pest outbreaks increase and invasive species spread, because warmer conditions let them survive in new places.
Crop yields change. In some places they fall, because of heat, drought and pests. This leads to food shortages.
People and other animals are forced to migrate, away from flooded coasts, failed farmland and places that are too hot or dry.

Worked example

Explain how global warming could force people on a low-lying island to leave their homes.

Higher temperatures melt ice sheets and glaciers, and warm sea water expands.
Sea level rises, and it floods the low land of the island.
Homes and farmland are lost, and salt water spoils the fresh water supply.
People can no longer live or grow food there, so they are forced to migrate.

Tips and tricks

Sea ice that is already floating does not raise sea level when it melts. Ice on land does: ice sheets and glaciers. Name those.
Ocean acidification is caused by carbon dioxide dissolving in the sea. It is not caused by acid rain.

6 questions, about 2 minutes.

It lands in your notebook with its questions as flashcards.

Impacts of climate change: 6 questions and answers

These are the quiz’s questions. Do the quiz first, then come back here for the ones that got you.

What causes ocean acidification?
- acid rain falling on the sea
- carbon dioxide dissolving in sea water (the answer)
- oil spills
- melting sea ice
More carbon dioxide in the air means more in the sea.
Why does the melting of ice sheets raise sea level?
- ice is heavier than water
- melting ice releases salt
- water that was stored on land flows into the sea (the answer)
- the ice was holding the sea back
Ice on land adds new water to the ocean.
What is permafrost?
- a type of glacier
- frost that forms each night
- ice floating on the sea
- ground that stays frozen all year (the answer)
Global warming is melting it.
Why might pests spread to new areas as the climate warms?
- there are fewer crops
- warmer conditions let them survive where they could not before (the answer)
- predators increase
- winters become longer
Cold winters used to kill them off.
Which is an impact of climate change on people?
- more ozone in the air
- stronger gravity
- forced migration (the answer)
- fewer daylight hours
People leave flooded or drought-hit land.
Why does a warmer ocean take up more space, even with no extra water added?Stretch
- salt dissolves faster
- waves become larger
- more rain falls into it
- water expands when it is heated (the answer)
This expansion is one cause of the rise in sea level.

6 questions

Tap an answer and you’ll see straight away whether it’s right, and why.

Worksheet

3 questions, 8 marks. Write your answers on paper, then check them.

Impacts of climate change

Cambridge IGCSE Environmental Management 0680 · 8 marks · papermunch.org

Name ______________________________ Date ______________

Explain why sea level rises as the Earth warms.[3]
Show answerHide answer
Ice sheets and glaciers on land melt, and the water flows into the sea. Sea water also expands as it warms. Both increase the volume of the oceans.
I got this one
Explain what causes ocean acidification.[2]
Show answerHide answer
The concentration of carbon dioxide in the atmosphere increases. More carbon dioxide dissolves in sea water, which makes it more acidic.
I got this one
Describe three impacts of climate change on food production.[3]
Show answerHide answer
Any three: crop yields change, and fall where it becomes hotter or drier; pest outbreaks increase; droughts and floods destroy crops; farmland is lost to the sea; food shortages result.
I got this one

Answers: Impacts of climate change

1. Ice sheets and glaciers on land melt, and the water flows into the sea. Sea water also expands as it warms. Both increase the volume of the oceans.
2. The concentration of carbon dioxide in the atmosphere increases. More carbon dioxide dissolves in sea water, which makes it more acidic.
3. Any three: crop yields change, and fall where it becomes hotter or drier; pest outbreaks increase; droughts and floods destroy crops; farmland is lost to the sea; food shortages result.