1.1 Atmosphere As A Global System

Question 1

Explain why low latitude locations receive more heat than places close to the poles.

Answer 1

• Radiation from the Sun
• Hits Earth
• Earth is sphere
• Radiation is more spread out at the edges (poles) due to the angle of incidence
• Colder
• Radiation is more concentrated at the centre (low latitude) due to the direct trajectory of the rays hitting the Earth
• Hotter

Question 2

How is a high pressure area different to a low pressure area? How does the weather differ?

Answer 2

High pressure
- air is cooled and so descends
- there is more air at the surface ('high' concentration)
- good weather (e.g. clear skies)
Low pressure
- air is warmed and so rises
- there is less air at the surface ('low' concentration)
-bad weather (e.g. rain)

Question 3

What are atmospheric circulation cells called?

Answer 3

Polar cell
Ferrel cell
Hadley cell

Question 4

Where is heat moved from and to? (think poles and equator)
And
How do atmospheric circulation cells move heat around the world?

Answer 4

• From Equator to Poles
• Sun heats unevenly causing air to heat and rise in different places (winds)
• Low pressure zone on equator hot air rises and moves to poles
• Wind travels from high pressure belts to low

Question 5

How do ocean currents move heat from the equator to the poles? How does the Gulf Stream work?

Answer 5

• warm region to cold region
• winds help transfer heat from equator
• heated water rises whilst cooled water descends
• cycle created (thermohaline circulation)
• deep currents (cold) driven by different densities
• shallow currents (Gulf stream) are warm
• Gulf stream…hot Labrador current…cold

Question 6

Explain how atmospheric circulation causes high pressure areas (dry) places like Tindouf.

Answer 6

• cool air sinking from Hadley and Ferrel cell
• creates warm and dry climates with lots of sun
• very arid areas are created
• no moisture and dry surface means little or no rain
• fairly large and direct amount of radiation from the sun so it has high temperatures creating more dryness

Question 7

Explain how atmospheric circulation causes low pressure areas (wet) places like Singapore

Answer 7

• located on a Inter-Tropical Convergence Zone
• lots of air is heated as it is on the equator (receives lots of radiation from sun)
• lots of air rises and expands
• rising air is very moist so it condenses when it rises creating cumulonimbus clouds
• lots of extreme rainfall creating wet and moist climate