Let's talk about Climate change –some details that may be new to youDavid MacKay FRS Department of Engineering University of Cambridge Former Chief Scientific Advisor Department of Energy and Climate Change |
Data from Free University of Berlin |
The "Lags or leads" story | ||||
Milankovitch cycles | ||||
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The Paleocene-Eocene Thermal Maximum | |||
Cumulative emissionsPredictions from Met office model |
Shallow core from the Dyer Plateau, Antarctic Peninsula
Robert Mulvaney, British Antarctic Survey |
Barlow et al, Stable Isotope Laboratory, University of Colorado, GISP2 "B" core |
Lorius, Merlivat, Jouzel, and Pourchet, 1979 - Dome C |
EPICA Dome C ice core |
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Temperature lags or leads CO2? |
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Temperature lags or leads CO2?
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The "Lags or leads" story | ||||
Milankovitch cycles | ||||
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The Paleocene-Eocene Thermal Maximum | |||
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Milankovitch cycles |
"When Fourier analysis was applied to deep-sea records in 1975, it
emerged that the oxygen-isotope series contained strong cycles with
periods near 100,000 years, 41,000 years, and 23,000 years. These are
precisely the periods expected if Earth's orbital elements
(eccentricity, obliquity, and precession) govern ice-age climates, as
proposed by Milankovitch Theory."
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What drives Glacial Cycles, W Broecker and G. Denton, Scientific American, January 1990, pp.43-50 |
EPICA Dome C ice core |
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wouldn't it be handy if we could look at the results of a mega-carbon-release experiment? |
Palaeocene/Eocene message:A release of one or two trillion tonnes of carbon over a few thousand years led to a 6°C global temperature rise. And mass extinctions. It took 120,000 years for the carbon to be removed.
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Global-mean surface temperature 1880-2013 (NASA GISS data). Grey line shows annual values, the blue line a LOESS smooth to highlight the long-term evolution. |
Act![or, to be explicit... assess uncertainty, assess options, assess costs and damages, then use decision theory and game theory] |
'Okay - it's agreed; we announce - "to do nothing is not an option!" then we wait and see how things pan out...' Lowe, Private Eye |
skepticalscience.com |
Temperature data, corrected for the ENSO effects Source: Real Climate |
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Information theory, inference, and learning algorithmsCambridge University Press Also available free online www.inference.org.uk/mackay/itila/ |
This book is free online | www.withouthotair.com |
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