Global atmospheric circulation

Question 1

What are winds?

Answer 1

Large scale movements caused by differences in air pressure

Question 2

How do differences in air pressure form?

Answer 2

Differences in temperature between the equator and the poles

Question 3

What is the pressure at the equator and the poles?

Answer 3

• Equator: low pressure
• Poles: high pressure

Question 4

Where do winds move from and to?

Answer 4

Winds move from areas of high pressure to areas of low pressure

Question 5

Define cells (geography)

Answer 5

Global atmospheric circulation loops

Question 6

What are the 3 cells (from equator to poles) (and latitudes)

Answer 6

• Hadley cell (0-30)
• Ferrel cell (30-60)
• Polar cell (60-90)

Question 7

What is the weather at high pressure?

Answer 7

Clear and sunny

Question 8

What is the weather at low pressure?

Answer 8

Cloudy and rainy

Question 9

What are the pressure belts called (from equator to poles)

Answer 9

• Equatorial low
• Sub-tropical high
• Sub-polar low
• Polar high

Question 10

What are the winds called in each pressure zone?

Answer 10

60-90 N: Polar easterlies
30-60 N: South westerlies
0-30 N: North East trade winds
0-30 S: South East trade winds
30-60 S: North westerlies
60-90 S: Polar easterlies

Question 11

Why is the equator warmer?

Answer 11

Sunlight hits the earth most directly at the equator, meaning the sunlight is spread over less area than other places because the earth is curved.

Question 12

What does hot air do?

Answer 12

Rise

Question 13

Where does hot air from the equator go?

Answer 13

It rises, cools and moves out to 30 degrees north and south of the equator

Question 14

What happens when risen air moves to 30 degrees north and south

Answer 14

It cools and sinks, creating a high pressure zone

Question 15

What are trade winds?

Answer 15

Surface winds blowing air towards the equator

Question 16

What are westerlies?

Answer 16

Surface winds blowing air towards the poles

Question 17

Where do trade winds blow from in the north and south hemisphere?

Answer 17

North hemisphere: from the NE
South hemisphere: from the SE

Question 18

What happens when trade winds meet at the equator?

Answer 18

They get heated and rise to form clouds

Question 19

What happens at 60 North and South?

Answer 19

The warmer surface winds meet the colder polar winds. The warmer air is less dense than the cold air so it rises, creating low pressure.

Question 20

What happens to the risen air at 60 North and South?

Answer 20

Some of the air moves back towards the equator and the rest moves towards the poles.

Question 21

What happens to the air at the poles?

Answer 21

The cool air sinks, creating high pressure. The high pressure air is then drawn back towards the equator as surface winds.

Question 22

What is the Coriolis effect?

Answer 22

Because the Earth rotates on its axis, circulating air is deflected toward the right in the Northern Hemisphere and toward the left in the Southern Hemisphere.

Question 23

What does the Coriolis effect cause?

Answer 23

Makes storms swirl clockwise in the Southern hemisphere and counterclockwise in the Northern Hemisphere.