Every dark cloud

Or no good deed goes unpunished.

The latest straw to be clutched at by global warming deniers is that in the early 1970s there was some concern expressed about "global cooling." It was based on the fact that there had been a cooling trend since about 1945, reversing a long warming trend. A handful suggested the possibility of a new ice age by projecting the result of the trend continuing for some time.

The source of this trend, which others said was likely just a blip in a longer-term warming trend (which is what it turned out to be), was thought to be the increasing concentration of particulates and aerosols in the atmosphere produced by industrialization, thus reducing the amount of sunlight reaching the Earth. (A similar, more dramatic, effect was the "nuclear winter" hypothesized to result from even a relatively small-scale nuclear war because of all the dust and soot that would be thrown into the atmosphere.)

The argument, stripped to its essentials, is "well, you were all wrong then, so you're all wrong now." Even leaving aside the obvious logical fallacy, it is, of course, a foolish claim: There never was a consensus about global cooling, unlike the strong one that exists now about global warming. It's also deceptive in that draws on a confusion between a prediction ("this is what will happen") and a scenario ("this is what can happen if such-and-such a trend continues").

Global warming is a prediction (with various scenarios within it about how severe the effects will be); global cooling was never more than a scenario. And one of the real reasons those scenarios never developed is that the trend of increasing air pollution was reversed by the increased attention to the environment and the resulting laws such as the Clean Air Act.

But as Barry Commoner is fond of pointing out, "everything is related to everything else." So of course nothing is ever simple. New Scientist's website for Thursday had the story:

The efforts of industrialised nations to cut smog pollution has had a bizarre side-effect - accelerating global warming.

New data show that after years of getting smoggier, our skies have become clearer since about 1990. And one effect has been to allow more solar radiation to reach the surface of the Earth.

The phenomenon known as "global dimming" has gone into reverse, according to research by Martin Wild at the Institute for Atmospheric and Climate Science in Zurich, Switzerland, and been replaced by "global brightening."

The smog particles, by shading the planet, had masked some of the effects of the increased concentration of greenhouse gases such as carbon dioxide.

And now the mask appears to be coming off. ...

The main cause of the global brightening, says Wild, is the clean-up of air pollution....

So should the world hurriedly reinstate smogs to stop global warming from accelerating? Probably not, as Wild points out that carbon dioxide lasts in the atmosphere for a century or more, whereas aerosols typically hang around for only a few days. So as carbon dioxide accumulates in future decades, we would need ever-thicker smogs to counteract it.

And another Science paper reports that current smog levels kill half a million people worldwide each year from heart and lung diseases.

Need another example? I have one, again from New Scientist, this from the issue of May 7.

Wind farms could damage the populations of some bird species if they are not carefully sited. That is the conclusion of a review of all the impact studies done so far.

The review focused on the overall number of birds in and around wind farms, rather than just the number killed by collisions with turbines, and included all rigorous studies done worldwide, from Scandinavia to Wyoming. "Available evidence suggests that wind farms reduce the abundance of many bird species at the wind farm site," it concludes.

The broader focus was what made the review significant and it will doubtless be used by groups opposing creation of wind farms in their areas. However, one of the authors noted that the report is not opposed to wind farms, only to inadequate care in their siting. "Birds would suffer much more from climate change if we don't" pursue alternative energy sources said Andy Pullin of the Centre for Evidence-Based Conservation at the University of Birmingham (UK). However,

"[i]f Britain builds as many wind farms as the government is talking about, it could use up all the offshore habitat for ducks and waders," warns the lead author, Gavin Stewart, also at the Centre for Evidence-Based Conservation.

Pullin suggested building the wind farms in deeper water farther from shore might prove better for the birds.

"Compared with past assaults, such as organochlorine pesticides, loss of hedgerows, illegal persecution of birds of prey and intensive agriculture, wind farms should be low down the scale of threats," says Mark Avery, director of conservation at the RSPB [Royal Society for the Protection of Birds]. "However, if we put them in all the wrong places then that picture would be very different." Yet when it comes to offshore wind farms, we do not even know what the wrong places are, Avery says, because so few impact studies have been done.

However, as David Suzuki says in the April 16 issue of New Scientist,

[c]limate change ... cannot be solved through good intentions. It will take a radical change in the way we produce and consume energy - another industrial revolution, this time for clean energy, conservation and efficiency. ...

But first we must accept that all forms of energy have associated costs. Fossil fuels are limited in quantity and create vast amounts of pollution. Large-scale hydroelectric power floods valleys and destroys animal habitat. Nuclear power is terribly expensive and creates radioactive waste.

Wind power also has its downsides. It is highly visible and can kill birds. The fact is, though, that any man-made structure can kill birds - houses, radio towers, skyscrapers. In Toronto alone, it is estimated that 10,000 birds collide with the city's tallest buildings every year. Compared with this, the risk to birds from well-sited wind farms is very low.

Yes, but that argument is limited to birds hitting the turbines, which is exactly what the new study goes beyond. The discussion continues toward a solution.

But I have a point to all this: Who pointed out the dangers of air pollution? Environmentalists and environmental scientists.

Who suggested answers to those dangers? Environmentalists and environmental scientists.

Who pointed out the dangers of global warming? Environmentalists and environmental scientists.

Who suggested answers to those dangers? Environmentalists and environmental scientists.

Who uncovered the problems created by their own proposed solutions? Environmentalists and environmental scientists.

Who is suggesting answers to those problems? Environmentalists and environmental scientists.

Who, that is, is prepared to question their own ideas and improve their approach as new information comes in? Those damned environmentalists and environmental scientists, that's who.

Compare that record with that of industry, even "environmentally friendly" industries like wind power.

The researchers are scathing about the poor quality of research into the impact of wind farms around the world. The findings of many studies are kept secret for commercial reasons, while supposedly public information produced for planning applications comes without raw information or is of poor quality, Stewart complains.

If you ever wonder which side - environmentalists or industry - you should trust in a dispute, that should answer the question.