1. Climate Change Case Study:
The Arctic

2. Why is the Arctic important?

4. Arctic surfaces reflect the sun’s heat
back out to space, and cool the surface

5. Surfaces reflects different amounts of heat energy.
Most is absorbed by dark forests that are expected to
replace tundra in the future; if sea ice is replaced by ocean
water heat balance will also change.
20% reflected
by tundra
vegetation
5% reflected
by black
spruce forest
85-95%
reflected by
snow
10% reflected
by ocean
water

6. Ice Albedo feedback loop

7. It re-distributes the earth’s heat
Deep, salty water
sinks, drawing in
warmer, fresher
water

8. Early warnings?• Ice withdrawal 'shatters
record'
• Arctic sea ice shrank to the
smallest area on record this
year, US scientists have
confirmed.
• The National Snow and Ice
Data Center (NSIDC) said the
minimum extent was 4.13
million sq km.
• The figure shatters all
previous satellite surveys,
including the previous record
of 5.32 million sq km in 2005.
• Earlier this month, it was
reported that the Northwest
Passage was open.
BBC 2007

9. Arctic plants capture the greenhouse gas carbon dioxide
faster than soils release it.
Arctic soils have accumulated 11% of the world’s soil
carbon
Carbon dioxide
uptake in slow
photosynthesis
Carbon dioxide
uptake in slow
photosynthesis
Carbon dioxide
release in very slow
decomposition
Permafrost

10. Computer models predict that the Arctic will warm
faster than anywhere else on earth, and
particularly in winter (up to 120
C)
Arctic
Global

11. Sea ice is already melting (apart from 2007-9!)

12. Storglaciären lost 29% of its mass between 1910
and 1980
Storglaciären 1910

13. Summer sea ice extent in mid September will
become reduced by 50% by about 2050

15. • There are some possible benefits of
changing ice conditions:
Making new gas and
oil fields more
accessible (25% of
reserves are in the
Arctic
Prolonging the
navigation season and
opening new shipping
routes 45% shorter
than through Suez

16. Increased
tourism and
mineral
exploitation
opportunities

17. • There is also
continued
pressure to
develop
‘domestic’
resources.
• These could
include the
ANWR

18. Significant wider impacts on people

19. Significant changes to vegetation belts

20. 1950
2002
Alaska
An invasion of trees and shrubs on tundra grasslands

21. Summary:
changes (by
2100) in sea
ice extent,
vegetation
and
permafrost.
ACIA, 2005