Grade 11 Geography - The Atmosphere - Summary

GEOGRAPHY
- GRADE 11 -



THE ATMOSPHERE
- Topic 2 -
Page 72-119




The Transfer of Energy and Energy Balance


Key Questions…
1. How is the Earth heated?
2. How does latitude affect the heating of the atmosphere?
3. How do seasons affect the heating of the atmosphere?


Ocean Currents:
Ocean currents are either warmer or colder than the surrounding area
 Warm ocean currents move from the equator towards the poles, so they transfer heat from
the tropical zones towards temperate zones
 Cold ocean currents move from polar regions towards the equator


Winds:
Winds are Moving Air
 If the wind blows from a tropical zone towards a cooler zone, it transfers heat energy and
warms the region it blows over. Wind can affect temperatures over land and sea surfaces
 If wind blows from a polar region towards a warmer region, it cools the region down. In this
way, winds to some extent restore the energy balance over the Earth’s surface

,High Pressure = Anti Cyclone = H Low Pressure = Cyclone = L
 Weather, sunny, dry, fair  Weather, cloudy, humid, storming,
precipitation

, Air masses:
What is an air mass?
 Body of air with common characteristics (Temperature, moisture, pressure)
 Take on the characteristics of Earth’s surface where they originate




Coriolis Effect
 Due to Earth’s rotation
N Hemisphere – Air always rotates to the Right
S Hemisphere – Air always rotates to the Left


Convection Cell (Movement of an Air Mass)
 Air moves from an area of H to L Pressure