Be alert but wary on climate claims
Professor John Carroll
First printed in The Age on 27 January, 2010.
Pre-Copenhagen, the global warming debate had been captured by prophets of doom and the language of apocalypse. This was particularly off-putting in a discussion that depends on high-quality science, cool logic, and careful argument. It raises old suspicions. The West has already experienced theories of impending environmental disaster with the Club of Rome launching a successful scare campaign in the 1970s about the world running out of food. Its book, Limits to Growth, sold 30 million copies. Hardly a decade had passed before its predictions were proved wrong.
Of course, the objective case for global warming is separate from the manner in which some of its proponents have publicised it. And, it should be judged on its own merits. Nevertheless, I must confess to being wary of causes that attract pseudo-religious enthusiasm and intellectual fanaticism.
Current predictions of global warming and its long-term effects depend on computer-generated mathematical models. There are two major problems with such models. First, their relationship to reality is compromised by the simplifying assumptions they have to make in order to reduce the number of variables they can take into account to a workable number.
In economics this means they are next to useless for long-term prophecy. We are confronted every day with how poor economic commentators are at prediction. If this is true in the domain of economics, how much more the case is it for climate, where the potential variables are vastly greater?
The second problem with mathematical models is that they assume current factors will continue as they are-major ones will stay major, minor ones minor, and no significant new ones will emerge.
History is a story of the rise of the unexpected. Having said this, some predictions are better than others. For instance, the Intergovernmental Panel on Climate Change's 2007 report projects greenhouse gas emissions. In the limited case of carbon dioxide over the next two decades, there is some plausibility to the predictions - given current dependence on coal-fired power stations and the long development times needed to switch modes of electricity generation. However, when it comes to linking emissions to rising world temperatures, the models become fanciful.
The New York Times, hardly an enclave of climate scepticism, featured an article on September 23, 2009, which admitted that global temperatures have been stable for the past decade, and may even drop in the next few years. Surely, this trend may be an anomaly, but its existence does raise a serious question mark, for all but true believers.
Some disciplines in both the arts and the sciences are highly speculative, and that makes their theories and predictions unstable. Does climate science belong here? I have my suspicions. For instance, climatologists told us for a decade or more that climate in south-eastern Australia - and in particular, rainfall - was determined by weather patterns and sea currents across the Pacific Ocean. Now, suddenly we are being told that it is rather the Indian Ocean that is critical.
The claims made about the science have been rash, asserting dogmatic certainty about human-induced warming when the reality is that the overall picture is quite unclear. This has now backfired, with the IPCC admitting mistakes in its 2007 report, and the East Anglia Climatic Research Unit, which the IPCC has drawn heavily upon, shown to have been, at the least, devious in the results it has made public.
There may be some link between the rashness of the global warming campaign and the haplessness of the politics that has followed. The best current bet is that, after Copenhagen, emission controls is dead as a serious international issue. And further, only some environmental disaster that can be convincingly linked to climate change will rekindle it. The ''sceptics'' have won the politics.
The clumsy politics is international and local. An emissions trading scheme, as proposed by the Australian Government, is very bad policy. It is a form of taxation on carbon under another name. To tax carbon will lead to thousands of pages of regulation - a godsend to bureaucracy, but paralysing for initiative and industry.
To give one example: taxing carbon, especially in Australia, would make little sense unless agriculture is included within the scheme. Farmers tell me that the amount of carbon dioxide released from the soil during ploughing depends on the depth of the furrows. There will need to be different regulations for different types of ploughing. Multiply this small particular across the range and complexity of Australian agriculture and our farmers will be looking at a code of regulations that will make the Taxation Act look like a kindergarten primer. One of the benefits of Copenhagen is that an ETS may now be politically dead in Australia.
Leaving aside the reservations I have expressed here, what if the gloomy predictions about global warming and its consequences turn out to be justified? It is not prudent for us humans to throw too much muck up into the sky.
So where does that leave us? We do need emission controls, but they should be kept as simple as possible. Why not just target major polluters, and notably coal-fired electricity generation? But Copenhagen has rendered even that futile for a trivial world polluter such as Australia, given that China and India have made it clear they will not be cutting back on their use of coal.