geo 8.1

• Differences between the two polar regions

  • Antarctica is completely covered with ice
  • Antarctica holds 90% of all the ice in the world
  • There are no land mammals, and no native peoples live in the region
  • The Antarctic is just as cold in summer as the Arctic is in winter
  • The Arctic (North Pole region) is partially inhabited
  • The Arctic is often defined as the area within the Arctic Circle
  • The Arctic covers parts of Russia, the United States, Canada, Greenland, Norway, Sweden, Finland, Iceland and the Arctic Ocean
  • The Arctic region consists of sea ice and pack ice
• Sea ice


  Chunks of floating ice called ice floes
• Pack ice


  Lots of ice floes piled together, usually disappears in summer
• Sometimes the July 10°C isotherm is used to define the boundary of the Arctic, and sometimes the northern tree line
• Polar zones or polar regions


  Start at 66½°N and 66½°S, much colder than the average temperature on Earth
• Reasons for the cold in polar regions

  • Tilt of the Earth's axis causes different amounts of sunlight reaching different locations
  • Albedo effect
• Differences between the Arctic and Antarctic regions

  • Antarctica is very mountainous
  • No influence from warm ocean currents
  • Extremely dry
• Polar lights


  Caused by the interaction of the sun and the Earth's magnetic field
• Polar lights formation


  1. Solar winds enter the Earth's atmosphere

  2. Electrically charged solar particles collide with air particles

  3. Coloured lights appear in the sky
• Electrically charged solar particles enter the atmosphere


  Can disrupt electricity networks and telecommunications