Climate Change Impact on Arctic Ecosystems Flashcards
How much more are high latitudes warming than the global average?
Around 4 times faster
What is polar amplification?
As snow melts, the darker ground and ocean surfaces will absorb more solar energy
Extra energy trapped goes into warming
Increased warming causes more snow to melt which then causes more absorption of solar energy and less reflection
Is a positive feedback loop
What is permafrost?
Permanently frozen ground
24% of land in northern hemisphere
Stores carbon as peat and methane
More than twice a much carbon is stored in permafrost than in the atmosphere
What causes permafrost thaw?
Due to active layer (aka surface layer) thickening/deepening into the permafrost
How is snow cover extent/duration changing?
Snow cover is lost faster in the spring/early summer
The growing season of no snow is now two weeks longer than the 1970s
Increases the plant productivity in the tundra
What is the possible positive to arctic greening?
May take up 7% more carbon from the atmosphere
How much is Arctic sea ice decreasing?
12.5% per decade
What are the four different sea ice and marine ecosystems?
Multi-year ice
First year ice
Marginal ice zone
Open water
What are ecological consequences of sea ice decline in birds?
Early ice retreat causes altered timing of zooplankton and forage fish and that means less food for seabirds (and mammals)
Warmer arctic causes sub-arctic marine birds to more northwards and that may decrease already declining ice associated birds (e.g. Ivory gull)
What are ecological consequences for Pinnipeds?
Less sea ice means there is less haul-out sites so population declines (for ringed and bearded seals and walrus)
Breeding habitat is becoming less stable so there is greater reproductive failure and so populations decline (hooded, harp,ribbon and spotted seals aka pack-ice breeding seals)
