Friday, May 1, 2009

Climate Change....in all fairness!





My last post celebrated climate change sceptic Ian Plimer's Heaven+Earth, so in all fairness I decided I should read a highly regarded view from the other side - the 'mainstream' view, if you like, so I could get an authoritative perspective that might put me right. Barrie Pittock was a lead author of the UN's IPCC reports. He is an Australian scientist who has been closely involved in the science of climate change for most of his long career with the CSIRO.

His recently published book is Climate Change: The Science, Impacts and Solutions. It's a very well written and lucid exposition of the accepted science and challenge of global warming.

The problem for me is that it raises more questions than it answers. It doesn't even try to prove the case that higher levels of CO2 in the atmosphere are causing the higher temperatures we've experienced throughout the 20th century. It simply asks you to accept that as fact. Plimer states categorically that higher levels of CO2 follow temperature increases, not the reverse. Most of the CO2 increase is natural, not man-made.

Look at these contrasting quotes:

Pittock: 'Scientists believe the rapid warming in the last several decades is due mostly to human-induced changes to the atmosphere, on top of some natural variations.' (p. 7)

Plimer: 'The last thirty years of weather are not in accord with what greenhouse models predict and can be far better explained by natural processes, such as solar variability'. (p. 392)

Pittock: 'Arctic sea ice is melting more rapidly than projected in the IPCC report, and reached a startlingly low minimum extent in September 2007. Moreover, permafrost is melting, floating ice shelves have rapidly disintegrated by processes not previously considered, forests are burning more frequently, droughts in mid-latitudes are getting worse, and so it goes. All this leads to the possibility of apocalyptic outcomes, with associated gloom and doom: multi-metre sea-level rise displacing millions of people, regional water shortages and mass starvation, conflict and economic disaster' (p. xiv).

Plimer: 'There is one constant: there is no shortage of self-styled climate experts willing to make diabolical predictions and to cast shadows of doom. Numerous scientific papers contradict the IPCC predictions of increased extreme weather, floods and droughts due to human-induced global warming. All of these scientific studies are ignored by the IPCC' (p. 483)... The slightest change in Nature is viewed as a message that we humans are changing the climate, that this is evil and that we must rid the world of this evil. To many, it is incomprehensible that Nature can change the planet or that humans are an insignificant short-lived recent terrestrial vertebrate living on a planet where natural forces are many orders of magnitude greater than any human force (p. 298).

Pittock: 'The truth is that in the reports by the...IPCC we have the most thoroughly peer-reviewed and carefully written series of reports summarising the science of a major issue that have ever been published' (p. 240).

Plimer: 'After reading a history of the 'hockey stick' no one could ever again trust the IPCC or the scientists and environmental extremists who author the climate assessments. The IPCC has encouraged a collapse of rigour, objectivity and honesty that were once the hallmarks of the scientific community' (p. 98)

I could go on and on with this stuff, but you get the point.

It's a vicious, no holds barred squabble. But when so much is at stake you can understand why.

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