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Climate change in the arctic and the
impact on marine ecosystems
Door: Anja Jansen
Begeleiding: Wim Klaassen
(NASA)
2004/’05
Increased warming at the poles
Research question
What are the influences of
climate change on the arctic
region and its marine
ecosystem?
Topics
Climate change
Melting of ice
Sea current changes
Ecosystem changes
The arctic climate
The climate of the arctic is distinguished by
its most important quality: cold.
Why is the arctic cold?
- the sunlight has to travel a long way through
the atmosphere
- high albedo of the arctic region
- energy lost by warmth transport in water
and melting of ice (in summer)
Temperature change in the arctic
Changes in
surface
temperature
between the
periods
1981-1992
and 19922003
(Comiso en Parkinson, 2004)
The Arctic oscillation
Arctic oscillation
Positive phase
Negative phase
The arctic oscillation seems to be staying in the
positive, warm phase (NOAA)
Ozone concentration in march 1979 (left) and
march 2003 (right).
(NASA)
Temperature change in the troposphere (left)
and the stratosphere (right) between the 80’s
and the 90’s of the twentieth century.
(Overland, Wang en Bond, 2002)
polar vortex
polar statospheric clouds
Trends in september
sea ice concentration
between 1979-1996 (a)
and 1979-2002 (b)
(NASA)
The expected loss of summer sea ice in
this century.
(ACIA report, 2004)
Changes in ice coverage on greenland
Source: Corell (2004).
Graph of annual average temperature and average total
precipitation for 1897 to 1998. Based on data for the Cascade West
Climate Division. The red lines show the general trend of both
temperature and precipitation, while the blue dots show the annual
variation of both values.
Annual runoff of
Lena, Ob and
Yenisey Rivers.
The Ob and
Yenisey Rivers
show an increase
since the 1980s
Seacurrent change
Slowing and possible disappearing Gulf Stream
in the north atlantic
Important changes
Warming
Melting of sea-ice
River runoff
Stratification
Slowing Gulf Stream
Stronger light
Average frostless period and the trend
between 1988 and 2001
Changes of primary production between the periods 1997-2002
and 1979-1986
Changes in sea-ice, permafrost area and
tree line expected by the end of the
century (ACIA)
ACIA
ACIA
Changes in water temperature and in fish
numbers observed in pacific fish harvests
(Klyashtorn and Smirnov)
Red line = herring
Blue line = temperature
ACIA
Influences on the ecosystem
Ozone depletion & sea-ice loss :
- Reactions with sunlight -> toxic chemicals
(hydroxyl, peroxide, super-oxide, etc)
- UV-B harmful for phytoplankton
- DNA damage in bacteria and larvae
- Fish get UV-B sunburns
Conclusions
The climate of the earth is a fragile
equilibrium which has been changed very often
in the earth’s history.
Climate change forces species to adept or
extinct, and helps new species to evolve, by
creating new habitat.
There have been many drastic changes in the
arctic environment, and to fully understand
the consequences on the ecosystem needs a
lot more research.