So global warming is a hoax.
We know this because last night a high-profile documentary on Channel 4 titled "The Great Global Warming Swindle" told us so over 90 long minutes.
For those who didn't catch it, the programme gathered together what Channel 4 called an "impressive roll-call of experts" who claimed man-made global warming is a myth, "created by fanatically anti-industrial environmentalists, supported by scientists peddling scare stories to chase funding, and propped up by compliant politicians and the media".
To support these claims it pointed to evidence that suggests increased levels of CO2 are the result rather than the cause of global warming; cited theories that argue increased sun activity is the primary factor driving higher temperatures; that the conventional wisdom fails to account for a period of global cooling last century; and claimed climate theories that challenge the conventional wisdom on manmade global warming are being silenced by a scientific community that unthinkingly dismisses them as the work of cranks in an attempt to protect budgets for their own studies.
It is a wonderful conspiracy story, told with panache and relying on just enough serious-sounding science and eminent-looking sources to make it all appear reassuringly plausible.
It is also, of course, mostly complete nonsense.
What the documentary omits to say is that it is widely accepted that temperature and CO2 levels are linked and that in prehistory temperatures would increase 800 years before levels of CO2 climbed. But as The Independent pointed out in a review of the documentary earlier this week "it is irrelevant to what is happening now, because for the first time ever enormous amounts of extra CO2 are being released".
Similarly theories that sun activity drives global warming are not new, and again what the programme fails to reveal is the fact that many studies that argue CO2 is the primary cause of climate change have also assessed the impact of the sun's activity and concluded it is too minimal to have had such a large effect. Clearly there are a handful of scientists who disagree and maintain the sun is the main cause, but a far greater number of studies insist this is simply not the case.
The programme also claims that the conventional climate science can not account for a 40 year period of global cooling that followed the Second World War. It argues that during this period of mass industrialisation CO2 levels rose and in complete contradiction to the expected result the temperature fell. What it omits to say is that, as explained over at Science Blogs, the conventional theory has accounted for this period of lower temperatures, claiming that it was largely caused by increased levels of sulphate aerosols.
Of course the programme makers and contributors can get round these glaring omissions by dismissing these rival studies are all part of the great global warming conspiracy, which aims to cripple the developing world and ensure that climate scientists can line their pockets.
But if these various dissenting voices are all being silenced and sidelined as part of this conspiracy how come they have a prime time documentary and global press coverage, including a piece this week in The Washington Times? If there is a massive conspiracy led by the establishment and the media how come leading opponents of man-made climate change such as Nigel Calder can still find a platform for their views in some of the world's most respected newspapers? It is hard to accept scientific debate is being stifled when these people are (quite rightly) completely free to publicly voice their concerns about the prevailing opinion.
It is far easier to believe that some scientists disagree on the causes of climate change - after all the whole practice of science is built around such disagreements. But how plausible is it that a large group of these scientists has become so desperate to win the argument, maintain their relatively small salaries, and destroy the industrialised world that they have set out to deliberately trick the finest political and business minds of their generation?
In short, it is possible to largely discredit this documentary without even mentioning the fact that the last time its maker, Martin Durkin, made a film for Channel 4 lambasting the environmental movement back in 1997 it resulted in his being slammed by the Independent Television Commission for misleading contributors and editing interviews to "distort" interviewees views. Channel 4 was ordered by the watchdog to issue a public apology, but proceeded to then commission Durkin to make several more highly controversial films on genetic engineering and the health benefits of breast implants.
Durkin is quoted as saying it took 10 years to get this latest film commissioned, looking at his track record of editorial sharp practices it is a miracle he got to make it at all.
In many ways it is a shame this film was made by such a blinkered polemicist, because despite all the omissions and irrational conspiracy theories it had an interesting story to tell. It raised the point that climate science is hugely complex and that there is not a complete consensus of opinion on its causes; it asked some pertinent questions about the extent to which we can be sure about any scientific theory, reminding us that only a few decades ago the primary climate concern was fear of global cooling; and it highlighted the vexed morality of asking developing countries not to use their fossil fuels.
The next time someone wants to make a documentary on global warming how's about commissioning a fully independent film maker who allows the scientists in Durkin's film to make their points and then talks to all those other climate scientists about their rival theories and why they think the deniers should be discredited. A full and open debate that lets the viewers decide which theories are most plausible based on the evidence and the strength of the argument – now that I would watch.
In the mean time the key question for businesses looking at the debate is what to do about this apparent uncertainty. How should we react to partisan films such as the Great Global Warming Swindle, or an Inconvenient Truth for that matter? How should this on-going debate and lack of certainty impact environmental policies?
The answer, as we've discussed before on these pages, is to accept that there is some doubt surrounding the climate change debate and then develop business strategies based on the probability over who is right and the risks that surround backing the wrong side.
On one side of the debate there is a large group of scientists and activitists who warn that if we don't invest a relatively small proportion of our income in new technologies and systems - many of which deliver long-term commercial and national security benefits anyway - then we are in danger of mass global instability, economic depression and even the collapse of civilisation. This group has the backing of many of the world's politicians who have promised legislation based on their recommendations and a large swathe of consumers who wish to buy products that they believe will help tackle global warming.
On the other side is a much smaller band of scientists and activists, who warn that the first group is the source of a massive hoax that they are playing on all of us in order to protect their salaries. They argue that if we do invest in the practices and technologies that are being recommended we would be forced to go through an expensive and unnecessary economic transition that would lead to some jobs being lost and potentially stifle development in poorer countries. This group has dwindling support in public life and has repeatedly had the credentials of some of their leading proponents discredited.
Business leaders know both schools of thought exist and some may even believe the arguments made by the later group. But until 100 percent conclusive scientific evidence emerges on either side corporate leaders have a commercial duty to assess which theory is most likely to be correct, which is most likely to impact the legislation they work under and the customers they target, and how the rival theories should feed into their risk mitigation strategies.
It's not a difficult decision and it is hardly surprising that sensible business leaders are choosing to ignore the siren song of those who deny manmade climate change and are instead declaring their support for the low carbon business models required to mitigate the growing legal, competitive and environmental risks associated with climate change.
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