The recent issues of Quadrant that provide only ‘denialist’ views on climate change issues must leave those concerned with the implications of climate change feeling shocked. Quadrant could analogously act as an outlet for the flat earth society but the purposes of supporting such a sustained attack on scientific logic would make no more sense than supporting climate change denialists without offering anything in the way of the majority accepted-science contrary view.
The most recent article by Bob Carter follows efforts by Ray Evans (here and here), Ian McFadyen (here) and William Kininmonth (here). All are attempts to debunk the global warming hypothesis as 'phoney science'. None of the contributions Quadrant provides are mainstream contributions to the climate change debate.
These denialist studies are surprisingly weak in terms of the force of their arguments. They apparently reject numerical model building of the type carried out by the IPCC on the grounds that it relies on a scientific consensus, that some parameters used are poorly known (true of most modelling!) and that the models contain biases consistent with the anthropogenic warming hypothesis. Of course, there is an abundance of different types of evidence supporting the claim of substantial anthropogenic induced rises in temperature over the past 100 years - this evidence is summarised below. The denialists represented however ignore the mainstream literature and cite only evidence that that they claim supports their cause. However many of the views they exposit are rejected by mainstream science and have been repeatedly refuted. For example, claims that warming has not occurred since 1998 and that the Hockey-stick graph is false have been shown false. The claim that temperatures have not increased since 1998 were rejected in the recent Garnaut Review (Garnaut commissioned two econometricians to test the claim) and in a careful study by meteorologists Robert Fawcett and David Jones. The claim that the 'hockey stick' wrongly suggests a recent sustained rise in temperatures is not something that supporters of the anthropogenic climate change hypothesis necessarily rely on to support their position – there is much additional evidence - but again the objections of the denialists have been broadly rejected by groups such as the National Academy of Sciences. Why has this counter-evidence not been cited?
The denialists present themselves as a persecuted minority whose views are being marginalised by groups such as the IPCC and most of the 2500 climate scientists who contribute to IPCC work. This is an unfair characterisation. The bulk of scientists do accept that climate change is anthropogenic though it is recognised that a small minority group dispute this consensus conclusions. But practical climate change policy calls for decisions to be made and, on the balance of probabilities, the consensus view is being relied on. Indeed it is difficult to see what other approach might be adopted. The insights of science are never final and it is almost certain that views will be refined and perhaps even revised dramatically. But the fact that there is not scientific certainty on climate change does not mean that action to deal with climate change should be stalled. Indeed, if the principle that no action in this world could be taken without definitive absolute certainty, few actions would occur in any area.
The upshot of the denialist position is that attempts to prevent ‘human-caused global warming’ will be a ‘costly, ineffectual and hence futile exercise’ (Carter). Climate change, if it does occur, should be addressed solely by adaptation policies so that society learns to live with heating effects. The claims about the primary role of adaptation and of the infeasibility, expensive climate change policies are discussed below.
Why are these conservative denialists so strident and seemingly irresponsible in rejecting the consensus science on climate change? Why do they not consider the possibility that they may hold erroneous views that, if they were accepted, would impose huge damages on our children and on future generations?
A standard text, Gordon Brown’s Ecological Climatology, summarises the conventionally understood facts on climate change scientist as they are widely understood:
1. The earth’s mean surface temperature increased by 0.74oC between 1906-2005.
2. The rate of warming over the last 50 years is almost double the rate over the whole 100 years. The latter half of the twentieth century was probably the warmest in 1300 years.
3. 11 of the 12 years from 1995-2006 are among the 12 warmest since 1850.
4. Not only air temperature but oceans and ground temperatures have increased.
5. Spring snow cover in the northern hemisphere has decreased with lakes and rivers freezing later in autumn and thawing earlier in spring.
6. Glaciers and permafrost are melting and Artic sea ice is shrinking.
7. Increases in concentrations of greenhouse gases are a positive radiative forcing that has warmed climate.
8. It is extremely likely that humans have exerted a substantial warming influence on climate. It is extremely unlikely that natural radiative forcing (solar irradiance plus volcanic aerosol) have had a warming influence comparable to that of anthropogenic radiative forcing.
9. Climate change models that include only natural forcings do not explain the late twentieth century warming while models that include anthropogenic forcings such as greenhouse gases and aerosols do simulate the warming.
10. The balance of evidence suggests that annual global mean surface temperatures will warm by from 1-6oC by 2100 in response to increased concentrations of greenhouse gases and other constituents.
The claims by the denialists mentioned that climate change can be dealt with entirely by adaptation rather than mitigation and that climate change measures will be prohibitively expensive and infeasible can be decisively rejected.
Adaptation policies alone will be insufficient to address the impacts of climate change partly because of impacts of change on the natural world. By in large there are extreme problems of facilitating biodiversity adaptations to climate change given rapid projected rates of temperature increase and the fragmentation of natural landscapes that inhibit natural migratory responses. In addition, the adaptation responses that would be called for to adapt to such things as sea level changes, changes in the agricultural sector and heat island effects in cities are often concentrated in developing country cities with low ability to invest in adaptation. Even in wealthy countries such as Australia it would be prohibitively expensive to protect the whole coastline from the effects of sea level change.
That mitigation efforts to thwart drastic climate change will be prohibitively expensive is rejected by major recent reports. Unmitigated climate change of 6oC would involve catastrophically large costs as suggested in the Garnaut Review. Every aspect of modern life would be destabilised and global as well as national welfare would be lower in 100 years than it is now (GR). It is worth noting that respected organisations such as the International Energy Agency in its recent World Energy Outlook 2008 forecast temperature rises of up to 6oC. At a discount rate of 2.7% the discounted costs of targeting 550 ppm emission targets by 2050 are 3.3% of discounted GNP while the costs of aiming for 450 ppm targets are 4.2% of GNP. These are significant costs but not prohibitively so.
The question whether climate change mitigation is feasible or not turns on the question of community and political will and whether or not an agreement can be forged at the United Nations climate change conference in Copenhagen next year to significantly cut developed country emissions and to reduce the growth rate of global emissions. Ross Garnaut’s assessment is that a 550 ppm target is more feasible than a 450 ppm target because of high offsetting growth in developing countries that will tend to swamp reductions in developed countries. With the policy framework he suggests an equal per capita emissions target across all countries can be achieved although the scale of reductions becomes harder with a long-term 550 ppm target. The argument for the desired global level of emissions cutbacks is can 'optimal insurance' argument - how much are we prepared to pay to help prevent the possibility of a severe long-tailed catastrophic climate future.
Efforts to forge an international agreement to cut emissions are not helped by claims that anthropogenic climate change is a phony science so that efforts to control emissions should not be made.
The views of the denialists need to be exposed for the delusions they involve and for the narrow perspectives they represent in the area of climate science.
