Transcript The Carbon Cycle and Global Warming

Science 10 O2
 Amount
of matter on Earth is constant
with the exception of a few asteroids
 NEED to recycle matter in order to
maintain our planet
 There are many cycles: carbon, nitrogen,
and water are examples.


Organic Matter: substances which contain atoms of
carbon and hydrogen, and often nitrogen and oxygen
as well. Ex: proteins, sugars, fats
Inorganic Matter: substances that do not contain carbon
AND hydrogen atoms. Ex: water, carbon dioxide,
ammonia
 Matter
is recycled by:
• Eating food (which is organic matter) and
through death.
• Decomposers are key in this recycling cycle.
 Carbon
is the key element for living
things.
 Each year, 50-70 billion tonnes of carbon
are recycled.



Photosynthesis: plants use light energy to combine
carbon dioxide and water to make glucose (sugar) and
oxygen
Respiration: living things use oxygen to break down
sugars and release water and carbon dioxide as the
sugars are broken down.
What do you notice about these two processes?
A
lot of carbon is being continuously recycled
by organisms, but a large amount of inorganic
carbon is also stored in three major areas:
• The atmosphere – smallest amount
• The oceans – dissolved CO2 for algae and
plants
• The earth’s crust – largest amount of storage
and can remain there for millions of years
• How do you think it gets released?
 Organic
carbon storage: in the bodies of
living things.
 When living things die, decomposers return
organic carbon to the cycle in an inorganic
form.
 Exception: large amounts of organic
carbons are stored in bogs.
• Little oxygen so decomposition is very slow
• Carbon remains locked in peat for many years.
• Compression of many peat layers = coal/fossil fuels
http://www.windows2universe.org/earth/climate/carbon_cycle.html
http://www.biology.ualberta.ca/facilities/multimedia/uploads/alberta/CarbonCycle
.html
 Humans
have sped up the release of
organic carbon through the mining and
burning of fossil fuels, and through
burning forests
 What does this contribute to?
 Global
warming is the increase in the
average temperature of Earth's nearsurface air and oceans since the mid-20th
century and its projected continuation.



The atmosphere is made up of layers of gases
When the sun’s heat warms the surface of the Earth, some of it is
reflected back into the atmosphere
The layers of gases can prevent the heat from the Earth to reflect
back from its surface to space, much like a greenhouse.






water vapour - occurs naturally in the atmosphere.
carbon dioxide - produced naturally when people and animals
breathe and from burning fossil fuels
Methane- comes from cattle as they digest their food. The gas also
comes from fields where rice is grown in paddy fields.
nitrous oxide - when plants die and rot, nitrous oxide is produced.
Ozone- occurs naturally in the atmosphere.
CFC’s
 Planet
becomes warmer:
• Weather patterns will change (depending on
area)
• Sea levels will rise
• Animals will be endangered
• Humans will be endangered
http://www.youtube.com/watch?v=5zLuqSYF68E


A carbon footprint is "the total set of greenhouse gas
emissions caused by an organization, event, product or
person.“
Greenhouse gases can be emitted through transport,
land clearance, and the production and consumption of
food, fuels, manufactured goods, materials, wood,
roads, buildings, and services.
 Solar
variation theory
 The warming is within the range of
natural variation and needs no particular
explanation.
 The warming is a consequence of coming
out of a prior cool period — the Little Ice
Age — and needs no other explanation.
 The warming trend itself has not been
clearly established, and therefore does
not need any explanation.
 Complete
the worksheet on the carbon
cycle using pgs 26-29
 Calculate
your carbon footprint using the
handout provided and list 3 ways you can
reduce your personal carbon footprint