Climate Science

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Climate Science
This presentation is designed for those who wish
to provide a reasoned argument against the ever
proliferating confusion over climate
science. Newer versions of this presentation and
others can be found at www.vicphysics.org
Follow the link from the Climate Change link on
the Home page. Be sure to look at the Notes
pages (below) for added comments to help in
presenting and for more information and sources.
Please feel free to email me with suggestions for
improvements or useful comments. This
presentation is designed for around an hour (or
more with expansion of some of the
points) Latest version 23 Feb 2010
Keith Burrows Science Teachers for Climate
Awareness
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Countering Climate Confusion

• What to say to sceptics

Download from www.vicphysics.org
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Countering Climate Confusion
CCC Main Points

• The basic reason for concern is the fundamental
  science (not rising temperatures or sea levels).
• CO2 captures heat radiation from the ground and
  sends it back.
• The greenhouse effect is well understood. It is
  crucial to life on Earth.
• We know we are increasing the greenhouse effect.
  The question is by how much and what will happen.
• We know the Earth is capable of wild swings of
  climate from Snowball Earth to Hothouse Earth.

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CCC Basic science

• First counter Why wont adding more CO2 to the
  atmosphere increase the greenhouse effect?
• Virtually all major scientific bodies have stated
  that continued anthropogenic CO2 emissions will
  almost certainly cause damaging climate change.
• Heres a partial list...

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Some scientific bodies who have issued statements
stressing the need for action on climate change
USA only

• National Academies of Science
• National Research Council
• American Association for the Advancement of
  Science (AAAS)
• National Oceanic and Atmospheric Administration
  (NOAA)
• National Center for Atmospheric Research (NCAR)
• NASA's Goddard Institute of Space Studies (GISS)
• American Institute of Physics
• Woods Hole Research Center
• Union of Concerned Scientists
• Federal Climate Change Science Program
• American Geophysical Union
• Geological Society of America
• American Chemical Society - (world's largest
  scientific organization)
• Federal Climate Change Science Program -
  commissioned by Bush!
• American Association of State Climatologists
• US Geological Survey
• Environmental Protection Agency (EPA)
• Pew Center on Climate Change

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Some scientific bodies who have issued statements
stressing the need for action on climate change
Rest of World

• UN Project on Climate Variability and
  Predictability
• United Nations Framework Convention on Climate
  Change (UNFCCC)
• United Nations Environment Program
• World Meteorological Organization
• International Council on Science
• The Royal Society (UK)
• The Institute of Physics (UK)
• Canadian Meteorological and Oceanographic Society
  (CMOS)
• Geological Society of London
• The Australian Academy of Sciences
• The Institution of Engineers Australia
• The Australian Meteorological And Oceanographic
  Society
• and many more!

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CCC Basic science

• Second counter
• It is easy to create confusion, about climate
  science, but much harder to clarify it.
• Denier arguments often look reasonable, but
  always fall down on close inspection. But all
  they need to do is create confusion.
• This is strong evidence that climate change is
  serious!

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CCC Risk management

• Third major counter

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• Would you get on this aeroplane if 1 out of 10
  engineers found dangerous cracks in the wings?

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• How about if 9 out of 10 engineers said there
  were dangerous cracks in the wings but 1 said
  they didnt matter?

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• Thats about the proportion of climate scientists
  saying climate change is dangerous!

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• Thats about the proportion of climate scientists
  saying climate change is dangerous!

This image was digitally altered!
Actually it is more like over 95
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CCC Risk Management

• Normally we dont take risks where lives are at
  risk.

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CCC Risk Management
www.gregcraven.org
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CCC Risk Management
www.gregcraven.org
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CCC Risk Management
Disaster!
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CCC Risk Management
What if we create a better world and it turns
out we didnt need to?
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CCC Risk Management
Do the sceptics ask themselves this question?
www.gregcraven.org
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CCC Risk management

• Third major counter
• Genuine sceptics will answer this by saying we
  should take precautions.
• Deniers simply dont seem to hear the question!

What if you are wrong?
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Climate sceptics and climate deniers

• Climate sceptics
• Scepticism is an important part of science.
  Scientists always try to question and test their
  theories.
• Scientific sceptics discuss their questions with
  other scientists through the peer reviewed
  journals.
• Climate deniers
• Deniers take the supposed debate to the public
  inappropriately. They avoid discussions with
  the scientific community.
• Deniers express no doubt about their position
  or they would have to take action in case they
  are wrong.

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Countering Climate Confusion

• So
• Basic science says adding CO2 must warm the
  Earth.
• Confusion is easy, but hides a potential
  catastrophe.
• Why on Earth would we risk the only planet we
  have?
• A little more on each of these...

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CCC Some basic science

• Why is the Earth at just the right temperature
  for us?

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The Big Picture
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The Big Picture
EARTH Atmosphere N2 , O2 , H2O and a little
CO2 Mean temperature 15oC Just right!
Why?
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CCC Some basic science

• Earths energy balance

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So what determines the Earths temperature?

• The balance between the energy coming in
• ... and that going out.

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CCC Some basic physics

• Earths energy balance
• Two simple laws of physics enable us to figure
  out the energy balance
• The Stefan-Boltzmann law... I esT4
• Wiens law... ?max 0.0029/T
• S-B just tells us how much heat a hot object
  radiates.
• Wien tells us what sort of radiation it will be.
• (but fortunately others have done the hard work
  for us!)

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CCC Some basic physics

• Svante August Arrhenius worked it out in 1896

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CCC Some basic physics

• Svante August Arrhenius worked it out in 1896

?
The Earths average temperature should be about
18oC
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CCC Some basic physics

• Svante August Arrhenius worked it out in 1896

Ah! The atmosphere must be trapping the heat
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CCC Some basic physics

• Svante August Arrhenius worked it out in 1896

?
But Oxygen and Nitrogen cant absorb the
infrared radiation
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CCC Some basic physics

• Svante August Arrhenius worked it out in 1896

It must be the water vapour and carbon dioxide!

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CCC Some basic physics

• Svante August Arrhenius worked it out in 1896

Together they absorb heat and re-emit enough
back to Earth to raise the temperature by
33degrees!
Doubling CO2 should raise the Earths
temperature about 5C
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CCC Some basic physics

• Earths energy balance
• Not all the IR radiation from the surface escapes
  immediately...
• or the average temperature would be a freezing
  18C
• No liquid water or clouds
• And no life!
• This is very well established physics!

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CCC Some basic science

• So how does the atmosphere keep us 33C warmer?

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CCC Some basic science

• How do air molecules trap the IR radiation?

Oxygen (O2) 21
Nitrogen (N2) 78
Carbon dioxide (CO2) 0.04 (was 0.03)
Water vapour (H2O) 0 1
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CCC Some basic science

• Nitrogen (N2) and oxygen (O2) molecules
• Two atoms tightly bound

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CCC Some basic science

• Water (H2O) and carbon dioxide (CO2) molecules
• Three atoms loosely bound

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CCC Some basic science

• Nitrogen and oxygen molecules
• Light photons (visible and IR) go right through
  N2 and O2

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CCC Some basic science

• Water and carbon dioxide molecules
• Infrared photons get absorbed by H2O and CO2
  molecules (and give them energy)

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CCC Some basic science

• Water and carbon dioxide molecules
• The H2O and CO2 dont keep the energy...
• they re-radiate it.

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CCC Some basic science

• Some of this re-radiated IR goes back down and
  warms the surface a little like a greenhouse...
• The so called Greenhouse Effect
• This keeps the Earth at a warm 15oC (average)
  instead of that freezing 18oC

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Countering Climate Confusion

• In other words we understand the basic science
  very well.
• The two key questions are
• By how much will our CO2 emissions increase the
  temperature?
• What will be the effect of that increase?

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Countering Climate Confusion

• By how much will our CO2 emissions increase the
  temperature?
• This is complex, but there are a number of
  different approaches
• Look at the physics (climate models)
• Look at the past (palaeoclimate)
• Look at the effect of recent changes (volcanoes
  etc)
• Measure it ...

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CCC Some basic science

• Car

70 ppm
0.6C
1C per 50 years
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CCC Some basic science

• But it is a lot more complicated than that!
• Thermal inertia (delayed action)
• Non-linear problem (2 2 4!)
• Feedback effects (positive and negative)
• This is the big one!
• But most reliable estimates are around 2C 5C
  per doubling of CO2 Most likely 3C
• Deniers have to find ways to claim that this is
  less than 1C! (Usually by dodgy calculations)

X
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CCC Some not so basic science

• This is where computer models come in handy!

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IPCC
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(IPCC graph)
The basic data needed is measured in various ways
and is well known. Notice that overall, incoming
equals outgoing (342 107 235). Also, that
large amounts of energy are absorbed and
re-radiated by greenhouse gases.
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CCC Some not so basic science

• Scientists put all the laws of physics and
  chemistry into computer models which can do the
  vast numbers of calculations needed.
• Some of the basic equations

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CCC Some not so basic science

• The models divide the atmosphere and ocean into
  cells about 1 km deep

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CCC Some not so basic science

• Remember this
• Economic computer models take human guesses about
  other humans behaviour.
• Scientific models take the very well known laws
  of physics and chemistry and apply rigorous
  maths.
• There is a VERY BIG difference between economic
  and scientific computer models!
• And climate models can be tested...

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CCC Some not so basic science

• Results of models

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CCC Some not so basic science

• Ignoring our emissions

Cooling
Wrong!
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CCC Some not so basic science

• Including our emissions

Warming
Correct!
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CCC Some not so basic science

• This is one reason climate scientists are
  confident that they have the basic science
  correct.
• And those models predict more warming 3? 5C
  this century...
• unless we cut emissions!

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Countering Climate Confusion Recap

• The basic reason for concern is the fundamental
  science (not rising temperatures or sea levels).
• CO2 captures heat radiation from the ground and
  sends it back.
• The greenhouse effect is well understood. It is
  crucial to life on Earth.
• We know we are increasing the greenhouse effect.
  The question is by how much and what will happen.
• We know the Earth is capable of wild swings of
  climate from Snowball Earth to Hothouse Earth.

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Palaeoclimate Confusion

• Plimer says the climate has always changed we
  just have to get used to it.

If we humans, in a fit of ego, think we can
change these normal planetary processes, then we
need stronger medication.
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Palaeoclimate Confusion
In the last 500 million years the climate has
swung between Hothouse Earth and Snowball
Earth

• Hothouse Earth
• Snowball Earth

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Palaeoclimate Confusion
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Palaeoclimate Confusion
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Palaeoclimate Confusion

• The last interglacial similar to current
  climate.
• Maybe 2C warmer than last century average...

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July 2009
Paul Blanchon's team at the National Autonomous
University of Mexico in Cancun has been studying
121,000 year old coral reefs in the Yucatan
Peninsula, formed
during the last interglacial period when sea
level peaked at around 6 metres higher than
today. His findings suggest that at one point the
sea rose 3 metres within 50 to 100 years.
Temperatures in that interglacial were only a
couple of degrees warmer than the 20th C.
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Climate science

• Sea level in last inter-glacial

12 m higher than today
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Palaeoclimate Confusion

• Climate change in the time of human civilization
  has been very minor ½C.
• Talk of warm Greenland is just a distraction.
• The climate change we are looking at is far more
  drastic than anything humans have experienced.

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Palaeoclimate Confusion
Pliocene
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Palaeoclimate Confusion
Pliocene
Sea levels between 25 and 75 metres higher than
today
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The rest of these slides are a selection from the
Whats wrong with deniers? presentation.
(MisconceptionsKB2.ppt)Download from
www.vicphysics.org
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Present Climate Confusion
The UN is using the global warming scare in
order to impose world government
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Science Teachers Climate Change

• Media coverage

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Science Teachers Climate Change

• Media coverage

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Science Teachers Climate Change

• Even in the more reputable press there is
  support for the sceptics

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1-1 It is getting cooler the warming has
stopped

• Lord Monckton of Brenchley

Only 7 years!
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1-1 It is getting cooler the warming has
stopped

• Lord Monckton of Brenchley

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1-1 It is getting cooler the warming has
stopped
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Typical yearly variation
compared to yearly warming trend
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CLIMATE CHANGE
WEATHER
Which is why we notice the weather more than
climate change!
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Many have suggested the cool spell in the N.
hemisphere suggests GW has stopped. What they
dont realise is that it was a local effect.
The rest of the world MORE THAN MADE UP for their
cooling. But many deniers live in the cool
regions!
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1-1 It is getting cooler the warming has
stopped

• For this reason we should look at decade trends
  or long term averages

CSIRO graph 11 year averages
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1-1 It is getting cooler the warming has
stopped

• For this reason we should look at decade trends
  or long term averages

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• Which is more likely?

OR
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But temperatures are falling while CO2 is rising!
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3-3 Correlation between temperature and CO2
levels.

• Typical denier graph
• Short term 1998-2008
• Starts on high ends on low
• Deceptive scale (looks like more than 10 years)
• Looks official

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3-3 Correlation between temperature and CO2
levels.
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3-4 Climate science isnt settled

• True! Science is never settled and climate
  activists should stop saying it is.
• The point is that there is a large amount of
  evidence to suggest that we are dangerously
  interfering with the climate.
• Science always works by different groups
  advocating different approaches and often getting
  different results.
• By continually checking and re-checking,
  eventually results begin to agree and consensus
  emerges.
• There is not yet a complete consensus, but there
  IS strong opinion that we are changing the
  climate dangerously.

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Today
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