The Great Global Warming Swindle, was based on graphs that were distorted, mislabelled or just plain wrong. The graphs were nevertheless used to attack the credibility and honesty of climate scientists.
A graph central to the programme’s thesis, purporting to show variations in global temperatures over the past century, claimed to show that global warming was not linked with industrial emissions of carbon dioxide. Yet the graph was not what it seemed.
Other graphs used out-of-date information or data that was shown some years ago to be wrong. Yet the programme makers claimed the graphs demonstrated that orthodox climate science was a conspiratorial “lie” foisted on the public.
Channel 4 distanced itself from the film:
Channel 4 yesterday distanced itself from the programme, referring this newspaper’s inquiries to a public relations consultant working on behalf of Wag TV, the production company behind the documentary.
However, crucially, the axis along the bottom of the graph has been distorted in the C4 version of the graph, which made it look like the information was up-to-date when in fact the data ended in the early 1980s.
This is handled by Stoat here.
If Mr Durkin had gone directly to the Nasa website he could have got the most up-to-date data. This would have demonstrated that the amount of global warming since 1975, as monitored by terrestrial weather stations around the world, has been greater than that between 1900 and 1940 – although that would have undermined his argument.
Hm… I wonder why?
The programme failed to point out that scientists had now explained the period of “global cooling” between 1940 and 1970. It was caused by industrial emissions of sulphate pollutants, which tend to reflect sunlight. Subsequent clean-air laws have cleared up some of this pollution, revealing the true scale of global warming – a point that the film failed to mention.
Other graphs used in the film contained known errors, notably the graph of sunspot activity. Mr Durkin used data on solar cycle lengths which were first published in 1991 despite a corrected version being available – but again the corrected version would not have supported his argument. Mr Durkin also used a schematic graph of temperatures over the past 1,000 years that was at least 16 years old, which gave the impression that today’s temperatures are cooler than during the medieval warm period. If he had used a more recent, and widely available, composite graph it would have shown average temperatures far exceed the past 1,000 years.
That’s exactly what I pointed out.