Impacts of Global Warming on the Arctic

Environmental Impacts
1. Increased extent and no. of Northern Coniferous (boreal forest) fires in Arctic Russia
  1. 10 million burn each year
    1. Losing 0.8% of the world's coniferous forest
  2. Boreal ecosystems = 37% of the world's carbon pool on land
    1. They are effective carbon sinks
      1. A forest, ocean, or other natural environment that absorbs carbon dioxide from the atmosphere
2. Tree line moving North into higher altitudes
  1. The edge of the habitat where trees grow
3. Thawing out of permafrost
  1. Permanently frozen ground
  2. Releases large quantities of stored methane
    1. ENHANCED GREENHOUSE EFFECT
    2. 1kg of methane will create the same warming as 21kg of carbon doixide
    3. The ground becomes softer which could lead to sinking of buildings and infrastructure
      1. Siberia
        Cracks have appeared in roads and airport runways
    4. Allows easier oil extraction + large scale agriculture
  3. Up to 40% of total amount (esp. in Siberia)
4. Tundra ecosystems being lost
5. Changes in biodiversity
  1. Northern shift of certain species
6. Increased coastal erosion
  1. Land weakening after permafrost melts
  2. More waves and storm surges
    1. Less protection of sea ice
Socio-economic Impacts
1. Threatening 155,000 Inuit inhabitants
  1. Weaker and thinner sea ice collapses
  2. Exposed to more ocean waves and storms
    1. Less ice to act as a natural barrier
  3. High risk of flooding
    1. 24 Inuit villages in Alaska are constantly under threat
  4. Decline in marine stocks
    1. Affects food and income source
      1. 70% of Inuit income is from paid employment or hunting-fishing
    2. To import replacement food would cost US $1m and provide less iron, magnesium and calcium then the natural diet
2. Loss of hunting culture + food security for indigenous peoples
Ecological Impacts
1. Warmer water = reduced quantity of marine plants
2. Less plants = less smaller + bigger fish species (e.g. halibut)
  1. This means less larger marine species (e.g. seals) = less polar bears
    1. NEGATIVE MULTIPLIER EFFECT
3. Hudson Bay is now ice-free for 3 weeks longer than it was in 1985
  1. Less time for polar bears to hunt the reduced no. of seals
    1. Less body fat = less chance of survival during summer
  2. ALTERNATIVELY: less ice = more sunlight for phytoplankton = more fish (that eat it) = more seals = more polar bears
4. Certain species may face extinction
Positive Impacts
1. Greater run-off = increased amount of nutrients + sediment = more coastal + wetland bog ecosystems = more habitats
  1. Annual freshwater run-off into Arctic Ocean predicted to rise by 15% (Siberia)
  2. NEGATIVES
    1. Releases methane
    2. Can impact OCEAN CURRENTS / THERMOHALINE CIRCULATION
      1. E.g. North Atlantic Drift that keeps North-West Europe warm
2. Increased access for marine shipping between Europe through the Pacific to Asia
  1. Majorly cuts cost of exporting products
    1. NEGATIVES
      1. Could lead to further exploitation of Arctic
      2. Greater frequent use of passage increases risk of pollution and oil spills
        Russia starts to allow nuclear wast disposal
  2. Before: only open 6 weeks in Aug-Oct
    1. Future: 120 days of ice free route by end of century
      1. 2007: North West Passage between Canada + Arctic melted enough to allow shipping through for the first time
  3. The Northern Sea Route

Próximo

Impacts of Global Warming on the Arctic

Descrição

Resumo de Recurso

Semelhante

	Criado por Melissa Cheung quase 11 anos atrás