Explain how atmospheric circulation assists in the redistribution of energy across the globe (Hadley)
- It is a thermally direct cell, warm air rises at the equator and travels in the upper atmosphere to 30N, it cools and sinks creating the Hadley Cell.
- It is a cell of high pressure.
- The winds associated with Hadley are the Trade Winds.
Explain how atmospheric circulation assists in the redistribution of energy across the globe (Polar)
- Thermally direct cell.
- Cold air sinking at the poles moves to 60N, forming the Polar Cell.
- Cell of high pressure.
- Winds = Polar Easterlies.
Explain how atmospheric circulation assists in the redistribution of energy across the globe
- Thermally Indirect Cell
- Cold air from poles meets the warmer air from tropics, causing air to rise creating the Ferrel Cell.
- Cell of low pressure
- Winds = Westerlies
Global Heat Budget (Curvature of the Earth)
- Both bands of insolation are the same width and therefore the same strength, yet the band which is near the North Pole has a greater surface to heat, unlike the band at the equator.
Thickness of the Atmosphere (Global Heat Budget)
- The further from the equator, the greater the amount of atmosphere the radiation has to penetrate.
- Energy is lost through scattering, absorption and reflection. 23% of insolation is absorbed by dust (19%) and clouds (4%)
GHB - Albedo
- The North and South Poles have high albedo, due to the ice caps being white, this reflects light.
- 30% of energy is reflected!
- Equatorial areas have low albedo due to the dark green colour and absorption through vegetation.
GHB - Tilt of the Earth
- In winter the North Pole is tilted away from the sun, therefore sun is concentrated at the Tropic of Capricorn in the Southern Hemisphere.
- In summer the South Pole is tilted away from the sun, therefore the sun is concentrated at the Tropic of Cancer in the Northern Hemisphere.
What do ocean currents move in?
Gyres
What are ocean currents greatly influenced by?
prevailing winds
What direction do ocean currents move in?
- They move clockwise in the Northern Hemisphere and anti-clockwise in the Southern Hemisphere
Where does the ocean + atmosphere move water from and to?
- They move water from areas of surplus at the equator to areas of deficit at the poles.
What land mass diverts ocean currents?
North America
What are the cold currents in the Pacific?
- The Californian brings cold water to the West Coast of the USA.
- The Kurlie Current is also a cold current that brings cold water down past Russia.
What are the warm currents in the Pacific?
- The North Pacific Drift brings warm water to parts of Canada.
- The Kirk Siri is a warm current and brings warm water past Indonesia towards Japan.
What is the last sentence needed for ocean circulation current model answers?
- Thermohaline currents are deep currents which originate in the Polar Regions where cold, dense water sinks.
- It then moved towards the equator where it heats up and becomes a surface current.
- This works in a conveyor like system.
What is the cold currents in the Atlantic Ocean?
- The Canary Current brings cold water to the West Coast of Africa
- The Labrador Current bring cold water to the East Coast of the USA
What are the warm currents of the Atlantic Ocean?
- The Gulf Stream brings warm water to the West Coast of the UK
- The North Atlantic Drift brings warm water past Greenland up to Russia
What equator receives the most heat from the sun
Thermal
In what months are the sun overhead, and where?
- June in the North
- December in the South
When the thermal equator is in the North what Air Mass does it pull?
- It pulls a Tropical Maritime, which brings warm and wet weather to Africa.
When the thermal equator is in the South what Air Mass does it pull?
It pulls a Tropical Continental which brings warm and dry weather to Africa
In what months does Agassiz receive no rainfall?
October, November, December, January, February, March and April.
Why doesn’t Agadez receive rainfall in these months?
In these months the thermal equator is in the south and Africa is covered by a Tropical Continental air mass, which brings hot and dry weather.
What months does Lagos receive peak rainfall?
June, July and August and this totals 1000mm.
