around the South Pole. It is a continent, surrounded by the Southern Ocean.

Why is Antarctica described as a desert?

It has very low precipitation. A desert is defined by dryness.

What do krill feed on?

phytoplankton. Tiny plants that float in the sea.

Which is an adaptation of seals to the cold?

a thick layer of blubber. The fat insulates them in freezing water.

Why does little of the sun's energy warm Antarctica?

The sun's rays arrive at a low angle and ice reflects them. Low angle and high reflection, plus dark winters.

The Antarctic ecosystem · Cambridge IGCSE Geography (9

In plain words

Antarctica is the coldest, windiest and driest continent, and almost all of it is buried under ice. Very little can live on the land. The life is in the sea around it, and all of it depends on one small animal.

8 things to know

Antarctica is the continent around the South Pole, almost all of it south of the Antarctic Circle. It is surrounded by the Southern Ocean.
It is cold because of its high latitude. The sun's rays arrive at a low angle, so their energy is spread over a large area, and the ice reflects most of it back. In winter there are months of darkness.
It is dry because of high pressure. Cold air sinks, so clouds rarely form, and the interior gets so little snow that it is a polar desert. Winds are very strong.
About 98% of the continent is covered by ice. Plants on land are limited to mosses, lichens and algae.
In the sea, tiny plants called phytoplankton are eaten by krill. Krill are eaten by fish, penguins, seals and whales, so the whole food web rests on them.
Abiotic (non-living) factors such as temperature, light and ice control what can live there. Biotic (living) things depend on each other for food.
Adaptations of animals: a thick layer of blubber, dense waterproof feathers or fur, a streamlined body for swimming, and huddling together to share warmth.
Adaptations of plants: mosses and lichens grow low to the ground, out of the wind, and grow very slowly.

Worked example

Explain why Antarctica is so cold.

It is at a high latitude, so the sun is always low in the sky. Its energy is spread over a large area of ground.
Ice and snow are white and reflect most of the sun's energy back into space.
For several months in winter the sun does not rise at all.

Tips and tricks

Antarctica is a desert because of low precipitation, not because of heat. "Desert" means dry.
Krill are the key species. If they decline, penguins, seals and whales all lose their food.

5 questions, about 2 minutes.

It lands in your notebook with its questions as flashcards.

The Antarctic ecosystem: 5 questions and answers

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

Where is Antarctica?
- around the North Pole
- around the South Pole (the answer)
- on the Equator
- in the Arctic Ocean
It is a continent, surrounded by the Southern Ocean.
Why is Antarctica described as a desert?
- It is hot.
- It is sandy.
- It has very low precipitation. (the answer)
- It has no wind.
A desert is defined by dryness.
What do krill feed on?
- fish
- phytoplankton (the answer)
- penguins
- seals
Tiny plants that float in the sea.
Which is an adaptation of seals to the cold?
- long legs
- thin skin
- a thick layer of blubber (the answer)
- bright colours
The fat insulates them in freezing water.
Why does little of the sun's energy warm Antarctica?
- The sun is too far away.
- The sun's rays arrive at a low angle and ice reflects them. (the answer)
- Clouds block the sun all year.
- The land is too high.
Low angle and high reflection, plus dark winters.

5 questions

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

Worksheet

3 questions, 9 marks. Write your answers on paper, then check them.

The Antarctic ecosystem

Cambridge IGCSE Geography (9–1) 0976 · 9 marks · papermunch.org

Name ______________________________ Date ______________

Explain why Antarctica receives very little precipitation.[3]
Show answerHide answer
It is an area of high pressure, where cold air sinks. Sinking air does not form clouds. Cold air also holds very little water vapour.
I got this one
Describe two ways in which penguins are adapted to the Antarctic climate.[4]
Show answerHide answer
They have a thick layer of blubber under the skin, which insulates them. They have dense, overlapping, waterproof feathers that trap warm air. (Also: they huddle together to share body heat.)
I got this one
Explain why krill are so important in the Antarctic ecosystem.[2]
Show answerHide answer
They feed on phytoplankton and are eaten by fish, penguins, seals and whales. Most of the food web depends on them.
I got this one

Answers: The Antarctic ecosystem

1. It is an area of high pressure, where cold air sinks. Sinking air does not form clouds. Cold air also holds very little water vapour.
2. They have a thick layer of blubber under the skin, which insulates them. They have dense, overlapping, waterproof feathers that trap warm air. (Also: they huddle together to share body heat.)
3. They feed on phytoplankton and are eaten by fish, penguins, seals and whales. Most of the food web depends on them.