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Climate Science
Science Teacher Conferences Feb 2013
Keith Burrows Download this presentation from: Australian Institute of Physics Education Committee
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What’s new?17 November 2012
IPCC 4AR 20072009
2012
The Stern review, published in 2006, pointed to a 75% chance that global temperatures would rise by between 2oC and 3oC
I would have been much more strong about the risks of a 4oC or 5oC rise.”
January 2013
Permafrost is melting (much) faster than expected
Permafrost is melting (much) faster than expected
The Age, UNEP
International Permafrost Association
“The latest estimate is that some 18.8 million km2 of northern soils hold about 1,700 billion tonnes of organic carbon.
[Australia = 7.7 million km2 ]
That is about four times more than all the carbon emitted by human activity in modern times and twice as much as is present in the atmosphere now.”
Permafrost is melting (much) faster than expected
Nature
But in News (very) Limited:
(28 Nov)
“Meanwhile, a United Nations report has warned that thawing permafrost covering almost a quarter of the northern hemisphere could "significantly amplify global warming" at a time when the world is already struggling to reign in rising greenhouse gases.”
“But it said studies of permafrost had proved inconclusive.”
“The complacency is astonishing. Last time the permafrost thawed, temperatures rose 6 degrees. Sea levels were up to six metres higher in the last interglacial period. But that was long before modern civilisation. Today's 7 billion people depend for their survival on reliable, stable sources of food and water. Billions live in vulnerable coastal areas. It may soon be beyond our powers - political or technological - to keep climate change in check, forcing us to turn our attention to managing and adapting to life-changing challenges. And these will be much more costly and difficult than the challenge of cutting our emissions.”
Arctic sea ice is declining rapidly
2007
Typical 1970’s 80’s Typical 2000’s
2012 – Record low September ice
Now about HALF what it has been for tens of thousands of years!
“But the global warming theory itself is based on just 16 years of warming – from 1980 to 1996.”
More Bolt Nonsense!
... the British Met Office released data showing no statistically significant warming for 16 years. ....
“Lindzen, arguably the world's most famous climate scientist, has argued for two years that there has been no warming since 1997 ...
... the rest of the world seems to have lost Australia's crusading zeal to stop a warming that for now seems to have stopped itself....
... increasing disasters we were told to expect have not happened.
Hun7/2/13
Daily Mail (UK)
13 October 2012
Q.1 “please confirm that they do indeed reveal no warming trend since 1997.”
As we’ve stressed before, choosing a starting or end point on short-term scales can be very misleading. Climate change can only be detected from multi-decadal timescales due to the inherent variability in the climate system....Eight of the top ten warmest years have occurred in the last decade.
...The current period of reduced warming is not unprecedented and 15 year long periods are not unusual.
Q.2 “Second, tell me what this says about the models used by the IPCC and others ...”
The models exhibit large variations in the rate of warming from year to year and over a decade, owing to climate variations such as ENSO, the Atlantic Multi-Decadal Oscillation and Pacific Decadal Oscillation. So in that sense, such a period is not unexpected...
Q.3 “Finally, do these data suggest that factors other than CO2 – such as multi-decadal oceanic cycles – may exert a greater influence on climate than previously realised?”
...they may act to slow down or accelerate the observed warming trend. ...also influenced by... changes in solar activity, volcanic eruptions or aerosol emissions. Combined, several of these factors could account for some or all of the reduced warming trend seen over the last decade
...global warming theory based on “just 16 years of warming” ??
or “no warming since 1997 ...” ??
no increasing disasters ??
Deniers will focus only on arguments about short term temperature rises (or not) and completely ignore (or totally misrepresent):
The basic science (and computer models) The extent to which we have changed the
atmosphere Arctic, Antarctic and glacial ice melting The danger of melting permafrost Increasing weather extremes The geological record The Earth’s energy balance Statements from the vast majority of climate
scientists and every scientific body in the world
Try 200 years of solid physics!!!
So what is the (Earth’s) ‘Greenhouse effect’ ?
It’s all just a bit of physics!
Actually it started with
Joseph Fourier (1820’s)
John Tyndall (1860’s)
Svante Arrhenius (1890’s)
Climate Science 101
“The Earth should be a lot colder than it is”
Joseph Fourier ~1820
Climate Science 101
Tyndall found it was the water vapour and carbon dioxide gases in the air
John Tyndall ~ 1860
Climate Science 101
Svante August Arrhenius worked it out in 1896It’s a matter of the Earth’s energy balance
Just how
wrong can Bolt
be?!!!
Climate Science 101
If more energy escapes than comes in we get cooler.
If less energy escapes than comes in we get warmer.
+33 + ? degrees
Climate Science 101
This is a bit like a greenhouse...
So it is called the “Greenhouse Effect” It keeps the Earth at a warm +15oC (average)
instead of that freezing –18oC
Greenhouse Effect = +33oC
Murdoch Media Bias
Alan Jones
addresses
an anti C-tax
rally in
Melbourne
''The notion of global warming is a hoax. This is witchcraft. Commonsense will tell you it's rubbish; 97 per cent of all carbon dioxide occurs naturally … 3 per cent around the world is created by human beings.''
Murdoch Media Bias
Alan Jones
addresses
an anti C-tax
rally in
Melbourne
'“And of course carbon dioxide isn’t a pollutant. It’s a harmless trace gas that’s necessary for life”Alan Jones, 2GB, 15 March 2011.
“Climate change is natural, just get used to it!”
“Since 1998 the Earth has been cooling”
“Climate change is crap”
Plimer says “the climate has always changed” – we just have to get used to it.
Where do they get it?
“If we humans, in a fit of ego, think we can change these normal planetary processes, then we need stronger medication.”
Climate science
300 ppm (or 0.03%) might not sound like much, but here is the effect of adding 300 ppm of ink to a glass of water:
Climate Science 101
The water is like the atmosphere – it has no effect on the light
The ink absorbs visible light just like the carbon dioxide absorbs infrared light
If we could ‘see’ in infrared the atmosphere would look quite opaque!
Science and politics don’t mix!
Unfortunately climate change has become a political issue
Many on the ‘right’ see government action as a threat to ‘freedom’
Many on the ‘left’ see it as an issue which supports their view of capitalism.
But it is fundamentally a scientific issue and the science is clear!
Global temperature is rising –just as the physics says it should
So are the consequences!
The denier view
ENSO and solar variability
Temperature
CO2
Sun
But what if?!!
Bolt says temperatures have not increased as predictedReally?
BEST
Denier tactics:
BEST
BEST
Climate extremes The RATE at which high temperature
records are being broken is INCREASING
Emitted Atmosphere
November 2012
“The lack of action on climate change not only risks putting prosperity out of reach of millions of people in the developing world, it threatens to roll back decades of sustainable development….
While every region of the world will be affected, the poor and most vulnerable would be hit hardest.”
“A 4°C world can, and must, be avoided.”
Dr. Jim Yong Kim President,
World Bank Group
Earth’s past climate
Pliocene CO2 drops from >400 ppm to ~300 ppm
PETM natural greenhouse event
Earth’s climate
Earth’s climate – looking at the past
The last ‘interglacial’ – similar to current climate.
Maybe ~2°C warmer than last century average...
last interglacial period when sea level peaked at around 10 metres higher than today. His findings suggest that at one point the sea rose 3 metres within 50 to 100 years.”
“Paul Blanchon's team at the National University of Mexico has been studying 121,000 year old coral reefs in the Yucatan Peninsula, formed during the
Temperatures in that interglacial were only a couple of degrees warmer than the 20th C.
July2009
10 m higher than today
Sea level in the last inter-glacial
Today
Earth’s climate – looking at the past
2010
Earth’s climate – looking at the past
+3°C
Pliocene
Earth’s climate – looking at the past
Pliocene
Sea levels between 25 and 75 metres higher than today
Earth’s climate
There is much more! Some past abrupt
climate changes have been linked to sudden releases of greenhouse gases
National Academies Press (USA)
Is the Earth warming?
Satellites can measure the heat escaping to space …
Low radiation High radiation
Is the Earth warming?
… and IT IS LESS THAN THAT COMING IN from the Sun!
The Earth must warm until they balance!
Reflected visible radiation Emitted IR radiation
Is the Earth warming?
Half a watt per square metre! That’s about: 20 times ALL the power being used by
humanity or 40,000 Hiroshima
bombs EVERY DAY This MUST heat
the Earth
Is the Earth warming?
Is the Earth warming? The Ocean
Is the Earth warming? Storms
It is the heat in the ocean that drives the weather
More heat
warmer water
more evaporation
more water vapour
more storms and rain
New England (USA) February 2013 - The second huge storm in four months (NASA)
Warming in the Arctic pushes more cold air up
Is the Earth warming? Cold winters
This higher pressure pushes frigid air further south
Is the Earth warming? Cold winters
Is the Earth warming? Glaciers
Is the Earth warming? Glaciers
Is the Earth warming? Glaciers
Is the Earth warming? Greenland
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Text
Perhaps the most dangerous aspect of Arctic climate change is the risk of passing tipping points…The Arctic region arguably has the greatest concentration of potential tipping elements in the Earth system, including Arctic sea ice, the Greenland ice sheet, North Atlantic deep-water formation regions, boreal forests, permafrost and marine methane hydrates. Recent analyses have added several more candidates…The Arctic therefore presents a test of our capacity as scientists, and as societies, to respond to abrupt climate change. But this response is being delayed because parts of the scientific community and the media have descended into semantic debate over whether Arctic sea ice has a ‘tipping point’. We argue here that this is distracting attention from the urgent need to focus attention on developing early warning indicators of abrupt change, addressing its anthropogenic causes, and rebuilding resilience in climate, ecosystems …
Is the Earth warming? Antarctica
“The Antarctic Peninsula is one of the fastest warming places on Earth – average temperatures from meteorological stations near James Ross Island have risen by nearly 2°C in the past 50 years.”
“Approximately 600 years ago the local temperature started to warm again, followed by a more rapid warming in the last 50–100 years that coincides with present-day disintegration of ice shelves and glacier retreat.”
“This new ice core record of Earth’s past climate puts into perspective how unusual the recent warming of the Antarctic Peninsula has been and why we should be concerned about the impact that continued warming will have on the Antarctic ice sheets.”
Is the Earth warming? Sea levels
thinkprogress.org
What to do?
By all means change the light bulbs (etc!) But the most important thing missing at
present is political will So we must TELL PEOPLE! Write to papers and politicians Join with others to spread the word
And if it’s NOT a big hoax?
