This article challenges several of the core assumptions on which the report on the Economics of Climate Change by Nicholas Stern is based. These include Stern's estimates of the potential for renewable energy and the capacity for carbon capture and storage in the combustion of fossil fuels for electricity.
Over the past few years there has been a remarkable surge in interest in the greenhouse effect and energy problems. It is now generally accepted that climate change is occurring, that it is due in large part to human activity, and that it is serious. Perhaps less well understood but also enjoying a remarkable increase in concern is the 'peak oil' thesis: the claim that we are close to the peak in petroleum availability and that this event is likely to bring about major economic disruption, unless substitutes are developed.
The report written by Nicholas Stern (1) has attracted widespread attention and appears to have been unanimously accepted as having established two crucial conclusions. The first is that the greenhouse problem can be solved, and the second is that it can be solved at negligible cost by 2050. I have written a detailed critique of the review (2) and will only briefly summarise the main difficulties here, before pointing to the profound implications that follow if Stern's conclusions are mistaken. My argument is that both Stern's conclusions are wrong: that the greenhouse problem cannot be solved in a consumer-capitalist society, at any cost. If this is so, then Stern has seriously misled the world, and current mitigation strategies cannot solve the problem.
THE CARBON TARGET IS TOO HIGH
The Stern review takes 550 parts per million (ppm), double the pre-industrial level, as the target limit for the maximum concentration of C[O.sub.2] in the atmosphere. However there is a strong case for concluding that a 400 to 450 ppm target runs a significant risk of producing more than a two degree rise in global temperature, and therefore of bringing about very serious consequences. Stern takes as his target reducing total C[O.sub.2] emissions from the present 26 giga tonnes per year (GT/y) to 18 GT/y in 2050. It is now generally accepted that global temperature increase should not be allowed to exceed two degrees Celsius. The Intergovernmental Panel on Climate Change's (IPCC) emission scenarios show that this would require the present level of emissions to be cut by 50 to 80 per cent by 2050 (or to 5 to 13 GT/y), and more or less eliminated entirely by 2100. (3) In the absence of mitigation efforts Stern indicates that C[O.sub.2] emissions could grow to 58 GT/y by 2050. (4) Stern has therefore taken a target that is well above what it ultimately has to be.
Stern recognises how much more difficult the 450 ppm target would be by stating that, for 550 ppm, the rate of reduction would have to be one per cent per annum but for the lower target it would have to be seven per cent per annum. (5) He says the reduction for the 450 ppm target would have to be 70 per cent and he, in effect, says that the associated cost to the economy would be unacceptable. The 7 graphs in the IPCC summary for policymakers (SPM) also show that the 550 ppm reduction curve is not far below the present level by 2050, but the 450 ppm curve is much lower.
It is increasingly accepted that the IPCC has significantly underestimated the pace and magnitude of climate change, partly because of the difficulty in taking into account feedback mechanisms such as the reduced capacity of warmer sea water to absorb carbon dioxide. Therefore it is likely that in future the desirable target will be seen to be under 400 ppm.
AN INAPPROPRIATELY LOW ENERGY BENCHMARK IS ADOPTED
Stern takes as the 2050 global energy consumption benchmark (under business-as-usual conditions) the amount that is also anticipated by the International Energy Agency (6) and other agencies, which is almost 2.5 times the present amount. But this is far below the amount that would be needed to provide present rich-world per capita energy use to all nine billion people expected soon after 2050. That would require more than four times the amount Stern takes as his target. If the target were the amount of energy needed to provide nine billion people with the per capita consumption that Australians are likely to have risen to by 2050 then, given the anticipated growth rate, the target is 9 billion x circa 200 giga-joules (GJ) x 2, that is, 3,600 exajoules (EJ)--an EJ is equivalent to the energy content of...