Transcript Trees and Climate Change

Trees and
Climate
Change
Global Warming
• the recent increase of
the mean temperatures
in the earth’s
atmosphere and oceans
which is predominantly
caused by human
induced greenhouse
emissions
• Effects: occurrence and
magnitude of rising sea
levels, precipitation
patterns, extreme
weather, biological
extinctions, and change
in agricultural production
Greenhouse Effect
• the process by which an
atmosphere warms a
planet’s surface. In this
effect, the sun sends out a
vast amount of short
wavelength radiation
(visible light) which
penetrates into the earth’s
atmosphere. ¼ of this
radiation is reflected back
into space by clouds and
the atmosphere. The
Earth’s surface absorbs the
rest, heats up, and radiates
this energy back as long
wavelength radiation
(infrared.) Infrared radiation
is trapped inside heat
trapping gases in the
atmosphere.
http://www.classroomencounters.com/
What are Northern Boreal
Forests?
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one of the three vast forest
ecosystems in the world along
with the temperate forest of the
mid-latitudes, and tropical
forest near the equator
supports a plentiful variety of
wildlife, which range from
endangered species to
extremely valuable wood.
Unfortunately, over half of the
existing boreal forest may
disappear, due to the effects of
climate change. This will pose
several problems: the loss of
trees and the carbon dioxide
that will be released from dying
trees when climate change
occurs.
http://magma.nationalgeographic.com/ngm/0206/feature2/images/ft_hdr.2.jpg
How do they affect climate?
• The boreal forests are
major carbon sinks,
absorbing an average of
between 700 million and
1.3 billion metric tonnes
of carbon each year.
• They can absorb13-24%
of approximately 5.5
billion tonnes of carbon
released annually from
the burning of fossil fuels
in 1980-1989
• They absorb co2 in the
atmosphere by
photosynthesis in which
they take co2 from the
atmosphere and release
oxygen
http://www.caribbeanedu.com/images/kewl/photosynthesis.gif
How are they affected by
climate?
• Climate change will
affect boreal ecosystems
in a number of ways: the
air temperature will
increase, rainfall and
humidity will change and
soils will turn dry, resulting
in a necessity of
adaptation that the
boreal trees can not
handle.
• the boreal forests are
likely to decrease in
area, biomass, and
carbon stock, along with
a noticeable loss in their
southern boundaries.
Tree Growth and
Inter-Decadal Climate Variability
www.usgcrp.gov/.../education/alaska/ak-edu-5.htm
Carbon Dioxide’s Influence
• If carbon dioxide levels
Carbon dioxide levels
were to double in
concentration, as
predicted will happen
over the next 100 years,
then the boreal forest
belts would shift
northward by about 500
km
• These new forest belts
would no longer be
Boreal but rather a more
fast-moving flexible
species such as those
with wider seed
spreading, fasterhttp://www.cossa.csiro.au/lb/lbbook/lcc/co2.jpg
growth,
and early maturity
What you can do
• Reduce the amount
of fossil fuel based
energy you use
(drive less; waste less
and and use less
electricity, heat, and
refrigeration)
• Join a group to plant
trees and prevent
forest fires such as:
http://www.ahc.sa.gov
.au/site/page.cfm?u
=160
Conclusion
• Boreal Forests contribute to
co2 sequestration as do
rocks, phytoplankton,
oceans, soil, and other
natural systems.
• As co2 levels go up, the
need to remove these and
other greenhouse gases
from the atmosphere
increases. Boreal trees play
a crucial role as living
carbon sinks and need to
be protected.
• Human rates of carbon
emissions must be reduced.
• Anyone can make a
difference!
• http://www.werc.usgs.gov/scot
er/2005/images/ss4.jpg