Atmosphere and weather 2.2 Flashcards
Why do areas nearer the equator receive more heat?
1) Insolation is concentrated near the equator, but dispersed near the poles with a lower angle of incidence.
2) Insolation near the poles has to pass through a greater amount of atmosphere as there is more chance of it being reflected back.
At what latitude is the point between a surplus in heat energy and a deficit in heat energy?
40 degrees north and 40 degrees south. ( the tropics )
How does the earth compensate for differences in global insolation so that there is a balance in temperatures?
Wind belts and ocean currents.
How do air masses gain their characteristics?
Via prolonged contact with the ground or sea surface.
Where do warm air masses form and move to?
- Sub-tropical high-pressure belts are the source regions for warm tropical air masses.
Where do cold air masses form and move to?
- Source regions for polar air masses are high-pressure systems over the continents.
What are ocean currents caused by?
Prevailing winds.
How is heat transfer distributed between winds and ocean currents?
- 20% ocean currents
- 80% winds
What is the pattern of ocean currents?
- A circular flow known as gyres
- Clockwise in the NH
- Anticlockwise in the SH
- Rotation of the earth forces the water to push eastwards
What is the Ocean Conveyor Belt?
- The slow circulation of deep-sea currents.
- It occurs from the polar regions where water is at its densest due to high salinity and cold temperatures.
- As it moves toward the equator, warm surface currents heat the conveyor belt bringing it up to the surface.
- Eventually, evaporation occurs, increasing salinity again, forcing the current to sink back to a cold and salty deeper current.
How do ocean currents affect the British Isles?
- The Gulf Stream transports heat northwards and eastwards across the North Atlantic which is a warm current.
- This means the British Isles have mild winters and relatively cool summers.
What is the Coriolis force?
- The deflection of the wind is caused by the easterly rotation of the Earth.
- Air is deflected to the right in the northern hemisphere and to the left in the southern hemisphere.
At what degrees is there a full day of light/darkness in the summer/winter solstice?
66.5 degrees
What are the three cells in the tri-cellular model?
Hadley cell, Ferrel cell, Polar cell.
What are Rossby waves?
Rossby waves help transfer heat from the tropics toward the poles and cold air toward the tropics in an attempt to return the atmosphere to balance via the westerlies.
