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Climate Science. Science Teacher Conferences Feb 2013. Keith Burrows Download this presentation from: Australian Institute of Physics Education Committee. Download this and other presentations from:. www. .org. What’s new?. 17 November 2012. 2012. 2009.
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Climate Science Science Teacher Conferences Feb 2013 Keith Burrows Download this presentation from: Australian Institute of Physics Education Committee
Download this and other presentations from: www. .org
What’s new? 17 November 2012 2012 2009 IPCC 4AR 2007
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 • The Age, UNEP
“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.”
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.”
Typical 1970’s 80’s Typical 2000’s
“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. Hun 7/2/13
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
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
Climate Science 101 If more energy escapes than comes in we get cooler. If less energy escapes than comes in we get warmer.
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 crap” “Since 1998 the Earth has been cooling” “Climate change is natural, just get used to it!”
Where do they get it? • 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.”
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!
Temperature CO2 Sun