Goh Cheng Leong Chapter 25 – Arctic or Polar Climate YouTube Lecture Handouts

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Goh Cheng Leong Chapter 25: Arctic or Polar Climate
Arctic or Polar Type
World Map
  • North of Arctic Circle
  • Ice-Caps – Greenland & highland of high latitude regions – permanent snow cover
  • Tundra climate – lowlands with few ice free months – coastal Greenland, North Canada, Alaska & Arctic seaboard of Eurasia
  • Ice Cap – Antarctica in SH - single stretch of ice-cap – permanent ice of 10,000 feet

Climate

  • Very low temperature
  • Range from (around 4 months have temperature above freezing point)
  • Winters – long & severe (weeks of continuous darkness)
  • Summers – cool and brief
  • Sun rays occur as faint rays – reflected by ground snow or ice melting
  • Soil water is frozen and summer heat can thaw for 6 inch of soil
  • Frost and blizzards are commonly seen – sometimes can be hazardous
  • Coastal Areas – Warm water meets cold land then thick fog develops
  • Precipitation as snow in winters & varies from ice crystals to snowflakes
  • 10 - 12 inches of snow make 1 inch of rain

👌 Convectional rain is absent – due to low rate of evaporation and lack of moisture in cold polar air

  • Summer precipitation – rain or sleet
  • Anticyclones over ice caps
  • Coastal areas – cyclones (tendency towards winter maximum when cyclonic activity is greatest) – rainfall upto 37 inches recorded

Vegetation

  • Tundra type – few plants can survive – deficiency in heat
  • No trees
  • Mosses, lichens and sedges
  • Drainage is poor – subsoil is permanently frozen
Plants in the Tundra
  • Hollows – ponds, marshes & waterlogged areas
  • Sheltered areas – birch, willow and alder
  • Coastal areas – hardy grass & reindeer moss (pasture for herbivores like reindeer)
  • Summers – berry-bearing bushes, Arctic flowers as Arctic Prairies
  • Birds migrate in summer back to polar areas
  • Animals – Wolf, Fox, Musk-Ox, Arctic Hare & Lemmings
Animals Polar Climate

Human Activities

Confined to coasts

Plateaus and mountains are inhabitable and snow covered

Semi-nomadic life

Eskimos – around 28,000 – hunters, fishers, food gatherers – now in permanent huts

Polar Eskimo

Polar Eskimos around Thule in NW Greenland – uncertain life – winters (compact igloos) & summers (portable tents of skins)

Igloos

Food – fish, seal, walrus, polar bear

Hunt caribou (Reindeer in America) for meat, milk, fat, skin and bones

Now Eskimos have permanent wooden houses with kayaks being replaced by speed boats, use rifles rather than traditional harpoons, now schools are established in those areas

Harpoons & Kayaks
Harpoons

Large farms for raising reindeer and breeding fur bearing animals

Nomads of Eurasia

Lapps – N. Finland & Scandinavia

Samoyeds in Siberia

Yakuts in Lena Basin

Koryak & Chuckchi in NE Asia

Importance & Recent Developments

👌 Discovery of minerals

  • Gold – Alaska
  • Nickel – Petsamo, USSR
  • Petroleum – Kenai Peninsula, Alaska
  • Copper – Rankin Inlet, Canada
  • Coal – Spitsbergen & Alaska
  • Iron Ore – Lake Superior & now Labrador (railway line to bring ores to . Lawrence River) ; Kiruna & Gallivare in Sweden

Ports on Arctic seaboard of Eurasia – Ship timber & fur from Siberia

👌 Igarka Port on Yenisey River – more ice-breakers keep the route open

  • Trying to grow hardy cereals for local needs in Arctic lowlands with warm currents and higher temperatures
  • Healthy air & germ free atmosphere is must for future colonization

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