Download Air, the Atmosphere and Greenhouse Gases - SEE

Living things have basic needs, including air. Air is vital for life and
is made up of gases. Natural atmospheric cycles like the carbon
and oxygen cycles have shown changes in recent decades as the
quantity of greenhouse gases being released into the atmosphere
has increased.
When human activities cause too many greenhouse gases to be
released into the atmosphere natural cycles are disrupted and cause
climate instability, climate change and global warming. Most
greenhouse gases come from human activities that burn fossil fuels.
In primary school, students need to have an understanding about
the fundamentals of air and its importance to all living things. They
can also be taught about the atmosphere more generally, about
natural cycles such as the carbon-oxygen cycles and about what
greenhouse gases are and where they come from.
These understandings can lead to activities that focus on why people
need to reduce greenhouse gas emissions and how we can all make the
AIR
necessary changes. This is especially in view that by 2020 these
CARBON – OXYGEN CYCLE
children will be the young teenagers/adults facing the consequences of
GREENHOUSE GASES: e.g.
our current decisions – including our decision to reduce Canberra’s
carbon dioxide
emissions by approximately 60%.
CLIMATE AND WEATHER:
weather refers to short term
temperature, wind and rainfall
changes, while climate refers to
the weather patterns in a place
over the long term.
CLIMATE CHANGE, GLOBAL
WARMING
1. Living things are connected. For example, humans breathe in
oxygen and release carbon dioxide which in turn is used by plants
and algae to produce more oxygen (carbon-oxygen cycle).
2. Humans have found and used coal, gas and oil which are formed
from plants that have decayed beneath layers of rock over millions
of years. These are called fossil fuels. When they are burnt in
power stations or burnt for fuel for vehicles, fossil fuels emit a
FOSSIL FUELS: buried, decayed
large amount of carbon dioxide – a greenhouse gas. The
plants which have turned into
greenhouse gases emitted through human activities have increased
coal, gas or oil.
the earth’s natural warming process – the greenhouse effect.
RENEWABLE ENERGY: solar,
3. Human activities are therefore causing an increase in carbon
wind, hydro-electric power.
dioxide and other greenhouse gases to be emitted into the
You could find out about
atmosphere which causes global warming, climate changes and
geothermal energy too.
climate instability. Note that there is a difference between the term
weather (generally short term) and the term climate (> 30years).
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1. How long can we live without air? What is the Earth’s air made
up of and what happens when we breathe?
Air is the name given to the part of the atmosphere used by animals
and plants (e.g. for breathing and photosynthesis).
We can live for only a few minutes without air.
Air contains roughly (by volume) 78.09% nitrogen, 20.95% oxygen,
0.93% argon, 0.039% carbon dioxide and small amounts of other
gases. It also contains water vapour. Humans, like all other animals,
depend on breathing in oxygen and breathing out carbon dioxide.
Air can be felt but not seen. Some science experiments that can help
demonstrate this could include:

Visualising the effects of air by observing the wind and/or
blowing air from our lungs into a paper bag
Change is
constant, yet

There are also some great diagrams/models available of the
Earth and its atmosphere to help visualise the concept and
show the various compositions of air :
often we fight it.
How can we view
the challenge of
climate change
and changes
science is telling
http://en.wikipedia.org/wiki/Carbon_cycle
2. What is the atmosphere? What is the carbon-oxygen cycle?
How does the interaction of animals and plants support life?
What are greenhouse gases? Why do they matter?
The atmosphere is a layer of gases surrounding planet Earth:
http://en.wikipedia.org/wiki/Carbon_cycle
A basic summary of the carbon-oxygen cycle: humans and other
animals breathe in oxygen and release carbon dioxide which in turn is
used by plants and algae to produce more oxygen:
us we must make,
http://en.wikipedia.org/wiki/Carbon_cycle
as an opportunity
Greenhouse gases include water vapour, carbon dioxide, methane and
nitrous oxide. For more information:
rather than a
www.science.org.au/nova/016/016key.htm
catastrophe?
The natural greenhouse effect
‘Without the greenhouse effect we would be living in a very chilly
place – the world's average temperature would be -19°C, instead of
the 14°C we are used to. So what is the greenhouse effect and how
does it make Earth around 33°C warmer? The natural greenhouse
effect is a phenomenon created by the heat energy radiated by the
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sun and greenhouse gases normally present in the atmosphere. In
simple terms, sunlight passes through the atmosphere, warming the
1. How long can we live without
Earth. In turn, the Earth radiates this energy back towards space. As
air? Why do astronauts need
it passes through the atmosphere, greenhouse gases absorb part of
suits, helmets and air tanks?
the energy, while the remainder escapes into space. This means that
some of the sun's energy becomes trapped – thus making the lower
2. What is in the air we breathe?
part of the atmosphere, and Earth, warmer.’ (source:
www.science.org.au/nova/016/016key.htm)
3. What do you know about
fossil fuels?
 Showing diagrams of the Earth’s atmosphere to help visualise the
concept http://en.wikipedia.org/wiki/Carbon_cycle
 Exploring the oxygen-carbon cycles through use of a candle in a
jar (tell children to only do this experiment with an adult). Here
you can light a candle and carefully place a jar over it. This can
be repeated with children timing how quickly the oxygen is used
and how quickly the candle goes out.
o Fire needs oxygen to keep going, so do humans and most
other living things!

Displaying diagrams of plants taking in CO 2 and giving off “O”
(oxygen), with people and other animals taking in oxygen and
breathing out CO2 http://en.wikipedia.org/wiki/Carbon_cycle
 Displaying diagrams that show the importance of greenhouse
gases and what they do: the blanket effect / the greenhouse
effect
3. How is the atmosphere getting out of balance now? What sort
of human activities combined with a sudden increase in the
human population cause unnatural increases in greenhouse
gases?
Too many greenhouse gases – too many blankets!
The natural greenhouse effect acts like a blanket for Earth. An
analogy for the increase in greenhouse gases in our atmosphere (a
consequence of human activity) is therefore too many blankets!
This increase in greenhouse gases and the subsequent warming
effect are causing the climate to change and become unstable,
resulting in, for example, more severe floods, droughts and storms.
www.csiro.au/science/Changing-Climate.html
www.science.org.au/reports/climatechange2010.pdf
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You could discuss with your class the difference between weather
1. Create diagrams showing the
carbon-oxygen cycle beside the
greenhouse gas effect showing
how there are too many
and climate; what climate change means; how scientists have found
the evidence for these changes; some of the effects of climate
change; and why scientists are urging people and governments to
make changes.
greenhouse gases
About 200 years ago there was an Industrial Revolution (see
2. Create a poster showing how
description below) where people found they could make things by
hot it can get inside a car in
using machines which burnt fossil fuels. For example, people burnt
summer along with a view of
coal to make steam to drive turbines which make electricity.
planet Earth getting too hot
Burning fossil fuels releases greenhouse gases. We now rely on
from too many greenhouse
electricity for many of our activities.
gases
Why not get students to create a list of what activities/appliances in
3. Show how electricity is made in
their home use electricity and try to identify where this electricity
various ways: from burning
comes from (e.g. fossil fuels or renewable energy sources such as
coal, from hydro power, wind
the sun or wind). www.actewagl.com.au/education/Energy
turbines and by solar panels
You can also demonstrate how electricity is made through simple
4. Make a working model of a car
with solar panels or a house
using solar panels to light
globes in the house
experiments. Try:
www.lessonplanet.com/search?keywords=electricity+experiments&
media=worksheets
4. What are fossil fuels? What good changes have they made?
What are the problems now? What is renewable energy?
5. On a map of your school’s
suburb, show how many
houses have solar hot water
and how many have solar
panels for electricity
Fossil fuels are fuels formed by plants which have been buried and
have decayed. The age of the organisms and their resulting fossil
fuels is typically millions of years and sometimes exceeds 650
million years (Wikipedia). Fossil fuels (coal, oil and gas) can be
burned to produce energy. This process releases greenhouse
gases. Fossil fuels are not renewable as they are not naturally
replenished within human timeframes.
‘Prior to the latter half of the 18th century, windmills and watermills
provided the energy needed for industry such as milling flour,
sawing wood or pumping water, and burning wood or peat provided
domestic heat. The wide scale use of fossil fuels, coal at first and
petroleum later, to fire steam engines enabled the Industrial
Revolution. At the same time, gas lights using natural gas or coal
gas were coming into wide use. The invention of the internal
combustion engine and its use in automobiles and trucks greatly
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increased the demand for gasoline and diesel oil, both made from
fossil fuels. Other forms of transportation, railways and aircraft,
Students have an understanding
about the importance of air, the
atmosphere and greenhouse
gases.
Students have more of an
understanding about how
also required fossil fuels. The other major use for fossil fuels is in
generating electricity and as feedstock for the petrochemical
industry. Tar, a leftover of petroleum extraction, is used in
construction of roads.’ (Wikipedia)
Australia has lots of black and brown coal that it uses to make
electricity.
human activities are causing an
www.actewagl.com.au/Education/energy/NonRenewableEnergy/Co
increase in greenhouse gases to
al/HowCoalIsUsed.aspx
be emitted into the atmosphere,
www.australiancoal.com.au/coal-and-its-uses_coal-uses-
and that this effects global
overview_electricity-generation.aspx
warming, climate changes and
climate instability.
Students have an understanding
about how humans have found
and used fossil fuels. They
understand that when fossil
fuels are burnt, they emit carbon
Renewable energy comes from natural resources such as sunlight,
wind, rain, tides, and geothermal heat, which are renewable
(naturally replenished). Renewable energy can also be used for
electricity generation and this process does not release
greenhouse gases. See the 2020 Vision energy story module for
further information and classroom activities.
dioxide and other greenhouse
gases.
Children can research how fossil fuels form and when they started
to be used by humans.
Students understand the basic
concept of renewable energy
sources.
Students explore positive and
As above, students could also create a list of what activities/
appliances in their home use electricity and try to identify where
this electricity comes from (e.g. fossil fuels or renewable energy
sources).
realistic ways to act for an
A Useful Resource: The Book ‘Our place in nature – past, present
environmentally sustainable
and future’ by Stephen Boyden –
future.
http://www.natsoc.org.au/html/publications/our_place.htm
and www.biosensitivefutures.org
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