Tuesday, March 06, 2007

Global warming: An inconvenient truth or hot air?

4 March 2007
The Independent
Geoffrey Lean reports

Everyone agrees global warming is a terrible fact of life. Right? Wrong. A film to be screened this week ridicules the Al Gore orthodoxy.

After two decades, the long scientific and political debate over whether human activities are warming up the Earth is finally over. Or is it? The world scientific community says so. Even the most recalcitrant governments, including the Bush administration, reluctantly agree. But the British media is characteristically unwilling to let an old row simply fade away.

On Thursday, Channel 4 will screen what it calls a "polemical and thought-provoking documentary" - The Great Global Warming Swindle - by one of the environmentalists' favourite hate figures, film-maker Martin Durkin.

It follows hot on the heels of a decision by David Miliband, the Environment Secretary, to send a copy of Al Gore's box-office hit, An Inconvenient Truth - which this month won two Oscars - to every secondary school throughout the country.

And the debate continues in the printed media with the Daily Mail and the Telegraph printing regular articles by sceptics and even The Independent, which - with this newspaper - presses for action to control climate change, giving space to the columnist Dominic Lawson, who rejects much of the green lobby's case. Yet, while contrarians remain common in broadcasting studios and newspaper offices, they are becoming increasingly hard to find in laboratories or governments.

Last month, the official Intergovernmental Panel on Climate Change (IPCC) - which brings together almost all the world's leading scientists in the field and all its governments - published the first instalment of its latest massive "assessment report", concluding that it was 90 per cent certain that human activities are heating up the planet. The conclusion was all the more authoritative as the IPCC is a cautious body that acts by consensus; all governments, including the United States, have to agree its conclusions.

Some scientists still disagree - that is the nature of science - but their numbers are diminishing, and few are leaders in their fields. A recent survey of 928 published scientific papers found not one that dissented over the reality of global warming. Even President Bush admitted - through gritted teeth - in January's State of the Union speech that the climate change presented "a major challenge".

Yet more recently, his main ally against the Kyoto Protocol, the Australian Prime Minister John Howard, has been forced into a U-turn by a massive Australian drought and an approaching election, announcing a ban on energy-wasting incandescent light bulbs.

And Mr Bush's best hope of a replacement - the Canadian premier, Steven Harper - has been forced by public opinion into a similar conversion.

But if environmentalists thought they could finally give up arguing, and focus entirely on promoting action, they can think again. For the clash between the Oscar-winning film and the Channel 4 production is likely to spark new public debate. Both are produced by controversial figures. Al Gore last week came under attack for hypocrisy, after it was revealed that he spends £15,000 a year heating his home, 20 times more than the average American house. And, as The Independent on Sunday has repeatedly pointed out , he failed comprehensively to practise what he preaches when in Government.

Martin Durkin, for his part, achieved notoriety when his previous series on the environment for the channel, called Against Nature , was roundly condemned by the Independent Television Commission for misleading contributors on the purpose of the programmes, and for editing four interviewees in a way that "distorted or mispresented their known views".

Channel 4 was forced to issue a humiliating apology. But it seems to have forgiven Mr Durkin and sees no need to make special checks on the accuracy of the programme. For his part, the film-maker accepts the charge of misleading contributors, but describes the verdict of distortion as "complete tosh."

His programme uncovers no startling new information, any more than does Mr Gore's film. The documentary repeats many of the arguments put in Britain by, among others what appears to be be something of a family cottage industry.

Standing with Dominic Lawson on the sceptic's barricades are his father (or to give him proper deference, Lord Lawson of Blaby) and his brother-in-law Christopher Monckton, Lord Monckton of Brenchley. Surprisingly, there is much common ground between sceptics and the environmentalists. Lord Lawson, for example, says that there is "little doubt that the 20th century ended warmer than it began".

He adds, similarly, that "there is no doubt that atmospheric concentrations of carbon dioxide increased greatly" during it.

He even agrees that it is "highly likely that carbon dioxide emissions" have played a significant part" in heating up the Earth.

He could hardly do otherwise. The measurements of what has happened are clear, and the basic science has been established, unchallenged for 180 years. Instead, the debate is about precisely what contribution to warming the pollution has made, whether it will continue and what to do about it.

The row concentrates on often arcane points of science, frequently delving far back into history. Three of them, raised in this week's documentary, are described above; in each the sceptics have a point, but fail to give the whole picture and so draw the wrong conclusions. Other arguments have been discredited.

Similarly, they emphasise that temperatures in Britain, Greenland and parts of Europe were warmer in the Middle Ages than they are now. That may or may not be true - since no accurate measurements were taken it is hard to be certain.

But, if so, it was only a regional effect: measurements of ice from the poles on which the sceptics place great reliance for other arguments (see table) show it did not happen worldwide. They also claim that tackling global warming would hurt the world's poorest by denying them fossil fuels. But renewable sources of energy should also be the poor's salvation.

They are abundant in the Third World and don't need costly distribution networks to get them to village. And even if the sceptics are right, and the bulk of the world's scientists wrong, there is still a compelling reason for cutting carbon dioxide emissions. For, as often reported in this newspaper, rising levels of the gas - in an entirely separate process - are killing the world's oceans by turning them acid.

Temperature

DURKIN SAYS: Studies of gases in bubbles of air in polar ice sheets reveal that in prehistoric hot periods temperatures began rising before C02 levels. So increasing concentrations of the gas are the result, not the cause of global warming.

GORE SAYS: "It's a complicated relationship, but the most important part of it is this: when there is more C02 in the atmosphere, the temperature increases." He shows two graphs of rising temperature and C02 levels over the past 600,000 years and says they "fit together".

WE SAY: Temperature and C02 are bound together. When one goes up, the other will follow. In prehistory temperatures often started rising 800 years before levels of the gas, and Gore evades this point. But it is irrelevant to what is happening now, because for the first time ever enormous amounts of extra C02 are being released.

The Arctic

DURKIN SAYS: Recent reports of how the amount of ice in the Arctic is shrinking have been exaggerated. The Arctic has always contracted and expanded over history.

GORE SAYS: The Arctic is a "canary in the coal mine". Since the 1970s ,the extent and thickness of its ice cap has "diminished precipitously". If we continue as we are, it will disappear during summers, profoundly changing the climate.

WE SAY: The amount of the ice ebbs and flows with natural warmings and coolings of the climate, and part of this shrinking is probably due to that. But this is being increased by global warming caused by rising levels of greenhouse gases, and these continue to go up. The Arctic is likely to be free of ice by 2050, for the first time in millions of years.

The sun

DURKIN SAYS: The sun is the main cause of global warming. The sun's activity increases from time to time, with increased solar flares, cutting down on cloud formation and raising temperatures on Earth. This activity correlates well with warmer periods over the past several hundred years.

GORE SAYS: The culprit is humanity's emissions of "huge quantities" of carbon dioxide and other greenhouse gases, which trap more of the infrared radiation of the sun that would otherwise escape out into space.

WE SAY: Variations in solar activity may have been responsible for past warm periods, though it's hard to be entirely sure because we have been taking good measurements of it only since 1978. But recent solar increases are too small to have produced the present warming, and have been much less important than greenhouse gases since about 1850.

http://news.independent.co.uk/environment/climate_change/article2326210.ece

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