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What is global warming?
The sun sends out energy
as heat and light. This
energy comes to our earth
during the day time.
Some of the sun’s rays get
‘trapped’ in the atmosphere.
Some of them get reflected
back into space.
The ones which get through the
atmosphere warm the earth up.
All the time, the earth
radiates heat into
space, which cools it
down. We only really
notice this at night,
when there is no
heating from the sun.
Some of the heat going out is
trapped by the atmosphere.
This is what makes our planet
warm enough to live on.
But if too much heat is
trapped, our planet will
warm up and the climate will
change.
What is the atmosphere and why
does it trap heat?
The atmosphere is the air around the
surface of the earth. It is made from a
mixture of gases. We need it for
animals and plants to survive.
Some of the gases act like a blanket,
trapping heat. These gases are called
‘greenhouse gases’.
This is known as the ‘Natural
Greenhouse Effect’. Without it, the
earth would be much colder.
(the atmosphere is
really much thinner
than it looks
above)
So why is global warming happening?
Some things that people do are increasing the
amounts of the greenhouse gases in the
atmosphere, so more heat is trapped.
The heating of the earth through human
activities is called the ‘Enhanced Greenhouse
Effect’ and this is causing the earth to heat up,
or global warming.
Global warming doesn’t just mean that the
earth gets hotter, it means that the whole
climate is changing.
GLOBAL WARMING IS the
consequence of
THE GREENHOUSE
EFFECT
So what is a
greenhouse?
How does it
work? What has
this got to do
with global
warming then??
Think about the greenhouse as if it was the planet and this is….
Explanation of the causes of global
warming
Human activity is adding more gases to the naturally occurring layer of
greenhouse gases. This thickens it so it cannot let as much heat return to
space and so the temperature of the earth gradually increases……
GLOBAL WARMING!
Name of gas
Contribution
Source(s)
Carbon dioxide
(CO2)
50%
From burning coal and oil, and the removal of vegetation
Chlorofluorocarbons
(CFCs)
20%
From air conditioners, refrigerators and aerosols
Methane
(CH4)
16%
From rice growing, animal waste, swamps and landfills
Ozone
(O3)
8%
From air pollution
Nitrous oxide
(N2O)
6%
From fertilizers and burning of coal and oil
Name of gas
Contri
Source(s)
bution
Carbon dioxide
(CO2)
50%
From burning coal and oil, and the
removal of vegetation
Chlorofluorocarbons
(CFCs)
20%
From air conditioners, refrigerators
and aerosols
Methane
(CH4)
16%
From rice growing, animal waste,
swamps and landfills
Ozone
(O3)
8%
From air pollution
Nitrous oxide
(N2O)
6%
From fertilizers and burning of coal
and oil
Example of the
Greenhouse Effect
The Sun’s energy
passes through the
car’s windshield.
This energy (heat)
is trapped inside
the car and cannot
pass back through
the windshield,
causing the inside
of the car to warm
up.
What’s the difference
between “global warming”
and “climate change”?
Difference
GLOBAL WARMING
is the increase of the
Earth’s average
surface temperature
due to a build-up of
greenhouse gases in
the atmosphere.
CLIMATE CHANGE
is a broader term that
refers to long-term
changes in climate,
including average
temperature and
precipitation.
Effects of Global Warming
Rising Sea Level
Increased Temperature
Habitat Damage and
Species Affected
Changes in Water Supply
The greenhouse effect and global
warming!
What’s the proof that
global warming is taking
place?
Portage Glacier
• Alaska
1914
Photos: NOAA Photo Collection and Gary Braasch – WorldViewOfGlobalWarming.org
2004
Colorado River
• Arizona
June 2002
Dec 2003
Global warming causes the polar ice
sheets melt. It increases the sea-level. It
will possibly rise 18 cm by 2030 and 58
cm by 2090. Flooding will probably occur
in lowlands. Many cities along the coast
may be under sea water.
Climate change
The Earth is
heating up.
This will cause
glaciers to melt
and sea levels
will rise.
The loss of polar ice
will have a profound
effect on nature in
particular animal
habitats.
Many of the world’s islands are already disappearing
beneath the sea.
The tiny island nation of the Maldives is in trouble. If global warming
continues, say scientists, the country could sink beneath the ocean
within 100 years. The average height of the islands above sea level is
1.5 metres and the rate of sea level rise is currently 59cm per century.
Why is global warming
happening?
Burning of Fossil Fuels
Pollution from coal,
natural gas, and oil
How Global Warming Works
Carbon Dioxide (CO2)
Fossil fuels (coal, oil, natural gas)
When did global
warming start?
Effects:
• Flooding
• Extreme Weather
• Climate change
• And more!!!!!!!!
Global Atmospheric Concentration of CO2
How is global warming
measured?
1000 Years of CO2 and
Global Warming
Temperature
(Northern Hemisphere)
Year
Year
2000
1800
1600
1400
1200
1000
2000
1800
1600
1400
1200
1000
Parts Per Million
Degree Celsius Increase
CO2 Concentrations
Billions of Metric Tons Carbon
Goal:
Reductions in
2007
CO2 Per Year
of Metric
Billions
Carbon Tons Carbon
Gigaton
Our Goal
2007
Reductions
in CO2
Per Year
Produce electricity
efficiently
Use electricity
efficiently
Vehicle efficiency
Solar and Wind
Power
Biofuels
Carbon capture
and storage
What’s being done now to
reduce our emissions?
Wind Power
Solar Power
Fuel-Efficiency
What can you do to help
solve the problem?
Use less:
Or use energy saving light
bulbs…..
Which will also save you money!
Simple Things To Do
Turn off your computer or the TV
when you’re not using it.
Take shorter showers. Heating water uses energy.
Keep rooms cool by closing the blinds, shades, or
curtains.
Turn off the lights when you leave a room.
Use compact fluorescent bulbs.
Or try and generate electricity in a
cleaner,
more environmentally friendly way?
Be Bulb Smart—Use CFLs
Incandescent
What’s the
difference?
Compact
Fluorescent
500 lbs.
of coal
•1,430 lbs. CO2 pollution avoided
•$30 saved
Simple Things To Do
.
Offer to help your parents keep the air filters on
your AC and furnace clean.
Walk short distances instead of asking for a
ride in the car.
Plant a tree.
Recycle.
Basically you need to reduce
your…..
All – to recognise that humans have
an impact on the environment.
Most – describe the impact of
deforestation and burning of fossil
fuels.
Some – know what the Kyoto
agreement is.
Kyoto agreement
• Written in Kyoto, Japan on 11th
December 1997!
• Came into force on February 16th 2005
• Many countries signed it and said they
would try and reduce greenhouse gases
being produced!