1.1 Global Circulation Cells

Question 1

What is the hottest part of the Earth?

Answer 1

The equator

Question 2

What are the coldest parts of the Earth?

Answer 2

The poles

Question 3

Why is the Equator the hottest part of the Earth

Answer 3

Because the sun’s rays are concentrated over a small area and strike at a right angle

Question 4

Why are the poles the coldest part of the Earth?

Answer 4

Because the solar radiation reaches the poles at a lower angle so the same radiation has to heat up a larger surface area. The radiation also has to pass through more atmosphere and travel and greater distance, so energy is absorbed.

Question 5

What does air pressure refer to?

Answer 5

Air pressure refers to pressure at the Earth’s surface

Question 6

What is the air pressure of a cyclone enviorment?

Answer 6

Low pressure

Question 7

What is the air pressure of an anticyclone enviorment?

Answer 7

High pressure

Question 8

How does a cyclone enviroment occur?

Answer 8

When air is heated it rises as it is less dense. As it rises it transfers heat to the atmosphere. It cools, condenses and usually clouds and rain occurs. Because there is ‘less air’ at the surface, it is now ‘low pressure’

Question 9

How does an anticyclone enviorment occur?

Answer 9

When air cools it becomes more dense. It falls and as it does transfers heat to the ground. It warms as it falls leaving clear skies and little/no rainfall. Because there is ‘more air’ at the surface, it is now ‘high pressure’.

Question 10

Give a definition of Atmospheric pressure

Answer 10

Atmospheric pressure is the ‘weight’ of the air and the force it exerts on the ground. It impacts the climate.

Question 11

Describe the atmospheric pressure around a desert

Answer 11

• The cool earth and air means less energy
in the air.
• This makes the air sink.
• The ‘weight’ of the sinking air exerts
more pressure on the ground, leaving an
area of high pressure. This means low
rainfall.

Question 12

Describe the atmospheric pressure around the tropics

Answer 12

• The warmth of the earth heats the air, increasing
the energy in the air.
• This makes the air rise.
• Rising air exerts less pressure on the ground,
leaving an area of low pressure. This means high
rainfall.

Question 13

How is wind affected in the Northern and Southern Hemisphere and what is this effect called?

Answer 13

Because of the earth’s rotation, the wind is deflected to the right in the Northern Hemisphere and left in the Southern Hemisphere. This is called the Coriolis effect

Question 14

What are the three types of atmospheric circulation cells?

Answer 14

Hadley , Ferrel and Polar

Question 15

What kind of pressure is found at the equator?

Answer 15

Low pressure

Question 16

What kind of pressure is found 30 degrees North and South of the Equator?

Answer 16

High pressure

Question 17

What kind of pressure is found 60 degrees North and South of the Equator?

Answer 17

Low pressure

Question 18

What are the two ways that heat is transfered?

Answer 18

Winds and oceon currents

Question 19

What happenes in step 1 when the solar radiation meets the Earth.

Answer 19

At the equator the Sun warms the Earth, which transfers heat to the air above, causing it to rise. This creates a low pressure belt. As the air rises, it cools and condenses forming clouds and rain.

Question 20

Shat happens in step 2 of the global circulation model

Answer 20

The cool, dry air moves out to 30° north and south of the equator.

Question 21

What happenes in step 3 of the global atmospheric circulation model?

Answer 21

At 30° north and south of the equator, the cool air sinks, creating a high pressure belt with cloudless skies and very low rainfall.

Question 22

What happenes in step 4 of the atmospheric circulation model?

Answer 22

The cool air reaches the ground surface and moves as surface winds either back 60° FERREL CELL to the equator or towards the poles

Question 23

What are surface winds blowing towards the equator called?

Answer 23

Trade winds

Question 24

What are surface winds blowing from the poles called and where do they blow from?

Answer 24

Surface winds blowing towards the poles are called westerlies. They blow from the NW in the southern hemisphere and from the SW in the northern hemisphere.

Question 25

Where do trade winds blow from and what do they form at the Equator?

Answer 25

Trade winds blow from the SE in the southern hemisphere and from the NE in the northern hemisphere. At the equator, these trade winds meet and are heated by the sun. This causes them to rise and form clouds.

Question 26

What happenes in step 5 in the atmospheric circulation model?

Answer 26

60° north and south of the equator, the warmer surface winds meet colder air from the poles, creating low pressure and frontal rain

Question 27

What happenes in step 6 in the atmospheric circulation model?

Answer 27

Some of the air moves back towards the equator, and the rest moves towards the poles, where the cool air sinks creating high pressure. The high pressure air is drawn back towards the Equator as surface winds.

Question 28

What are oceon currents?

Answer 28

Ocean currents are large scale movements of water that transfer heat energy from warmer to cooler regions.

Question 29

What are surface currents and how do they help? Given an example.

Answer 29

Surface currents are caused by winds and help transfer heat away from the Equator, e.g. the Gulf Stream brings warm water from the Caribbean and keeps Western Europe warmer than it would otherwise be.

Question 30

What are deep oceon currents driven by?

Answer 30

Differences in water density

Question 31

Explain how currents are created at the poles.

Answer 31

When water freezes at the poles, the surrounding water gets saltier, increasing its density. As it gets denser, it sinks, causing warmer water to flow in at the surface — creating a current. This warmer water is cooled and sinks, continuing the cycle.

Question 32

What is the cycle of cooling and sinking in a loop around the Earth called?

Answer 32

Thermohaline circulation.

Question 33

What is an ITCZ?

Answer 33

Inter-tropical Convergence Zone