Recent issues of Quadrant contain a number of ‘denialist’ views on climate change issues that will leave those concerned with the implications of climate change troubled. Quadrant could analogously act as an outlet for the flat earth society and the outcome of supporting such a similar 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) and papers by Ian McFadyen (here) and William Kininmonth (here). All are attempts to debunk the global warming hypothesis as phoney science. None of the Quadrant contributions provide a mainstream contribution to recent climate change debates and indeed the minority views of these denialists are not set in the context of the broader debate.
The denialist studies are surprisingly weak in terms of their force of argument. The authors apparently reject numerical model building of the type carried out by the Intergovernmental Panel on Climate Change on the grounds that the IPCC relies on a scientific consensus (not in itself something reprehensible), that some parameters used in the modelling are not known with certainty (true of most modelling!) and that the models used contain biases consistent with the anthropogenic warming hypothesis (somewhat unfair since they do account for natural radiative forcings). The authors implicitly question the incentives and integrity of researchers carrying out these mainstream studies while complaining at the same time they they themselves arec under the same sort of credibility attack from mainstream scientists. Moreover, it is true that prominent members of the climate denialist camp, such as Fred Singer, have also in the past denied connections between passive smoking and lung cancer. Singer has also denied that the ozone layer is being depleted and denied that there is a connection between this depletion and the incidence of cancer. All of these claims have been refuted by mainstream science.
It is difficult to make much sense of the denialist claims with respect to climate given that there is an abundance of different types of evidence supporting the claim of substantial anthropogenic induced rises in temperature over the past 100 years. For clarity I summarise this below.
The denialists represented in Quadrant however largely ignore this mainstream literature or treat it dismissively and cite only evidence and counter-claims that they see as supporting their position. However many of the views they exposit are rejected by mainstream scientists and have been repeatedly refuted as they are endlessly recycled. For example, their claims that warming has not occurred since 1998 and that the Hockey-stick graph is a fiction have themselves been refuuted using careful statistical study. The claim that temperatures have not increased since 1998 were rejected in the Garnaut Review - Garnaut commissioned two respected econometricians to test the claim - and in a suibsequent careful study by meteorologists Robert Fawcett and David Jones. While denialists might not agree with these counterarguments they cannot simply ignore their existence and declare as an uncontested and obvious fact that temperatures have not increased since 1998.
The claim that the 'hockey stick' wrongly suggests a recent, distinctive sustained rise in temperatures is not something that supporters of the anthropogenic climate change hypothesis necessarily rely on to support their position – as the Stern Review points out there is much additional evidence - but the specific objections raised by denialists have been broadly rejected - with some qualifications - by groups such as the National Academy of Sciences. Why has this counter-evidence and the counter-views not been cited in the Quadrant articles? It is not self-evident truth that current global mean temperatures are simply a repeat of past recent experience in terms of peaks.
The denialists present themselves as a persecuted minority whose views are being marginalised by groups such as the IPCC and by most of the 2,500 climate scientists who contribute to the IPCC work. This is an unfair characterisation and a slur on the integrity of these workers. Most scientists do accept that climate change is anthropogenic though it is recognised that a small minority group dispute this consensus conclusion. But practical climate change policy calls for decisions and, utilising a 'balance of probabilities' argument, the consensus view is being relied on for public policy purposes not the view of a tiny group of scientists who reject the mainstream science. Indeed, it is difficult to see what other approach might conceivably be adopted from the perspective of policy. The insights of science are never final and it is almost certain that current climate science views will be refined and perhaps even revised dramatically. But 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, not much would ever happen.
For non-scientists such as myself who are forced to make judgements on climate change in order, for example, to make informed electoral choices the responsibility is to be as informed as possible and then to respect the consensus views of mainstream science. This is not to say that these views may not be one day overthrown by new scientific findings – it is the duty of scientists to probe and attack each other’s work – but this does not mean that citizens should endorse the views of a minority of scientists who hold what seem to be implausible views at odds with standard science.
Indeed it seems that the denialists are behaving in a strident and seemingly irresponsible way in rejecting the consensus science on climate change without at least assembling and taking seriously the alternative consensus evidence and presenting the debate in a balanced way. 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? Is it only that their views have finally not been accepted in public debates that makes these minority-view scientists strike out with their strong claims?
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). Therefore climate change, if it does occur, should be addressed solely by adaptation policies so that society learns to live with heating effects. These claims about the primary role of adaptation and of the infeasibility, expensive climate change policies will be discussed below.
First let me cite from a standard text, Gordon Brown’s Ecological Climatology, what are the conventionally understood facts on climate change science. These views cannot be accepted by denialist scientists since they imply that their core beliefs are false.
1. The earth’s mean surface temperature has 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.
These widely accepted views contradict denialist claims. Denialists who wish to have their views taken seriously should at least admit that these are consensus views and consider them seriously because wrongly rejecting these views can have serious implications in terms of social costs.
The claims by the denialists 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.
There is nothing a priori wrong with the claim that adaptation policies alone can deal with climate change. But the empirical evidence on costs suggests that this approach is not viable. Adaptation policies alone will be insufficient to address the impacts of climate change partly because of impacts of change on the natural world. For example, 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' adaptation responses. In addition, 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 megacities 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 sea level change changes contingent on climate 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 - respected organisations such as the International Energy Agency in its recent World Energy Outlook 2008 forecast temperature rises of up to 6oC. Every aspect of modern life would be destabilised by such temperature changes and global as well as national welfare would be lower in 100 years than now. This is a catastrophic outcome that is worth focusing on even it it is a relatively low probability event because of the extraordinary costs associated with it. Rates of mean warming of more than 3oC would be very likely (Stern estimates the probability as 0.69) with the 550 ppm emmission targets that are endorsed in reports such as the Stern and Garnaut Reviews. The best science that we have suggests that this degree of warming would be associated with the destruction in Australia of the Great Barrier Reef, the Victorian Alpine biodiversity habitats, Kakadu National Park and irrigated agriculture in the Murray-Darling Basin. If the minority view of the denialists were accepted as the basis for public policy and it were wrong the costs would be extraordinarily high.
At a discount rate of 2.7% the Garnaut Review estimate that 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 Stern Review reaches much the same conclusions - the costs of not acting strongly enough to deal with climate change greatly exceed the costs of taking decisive action to address it. Accounting for risks of catastrophic change Stern computes the cost of not addressing climate change as a permanent loss in consumption per head of 5-20% whereas the permanent cost of stabilising emissions at between 500-550 ppm would be around only 1% of GNP.
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. 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 society's 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 '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. These minority views offer the potential for substantial risks to society if they were adopted and proved to be wrong.
One can ask why are these conservative denialists so strident and seemingly irresponsible in rejecting the consensus science on climate change without at least assembling the alternative consensus evidence? 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? One can conjecture that it is only that their views have finally not been accepted in public debates that makes these minority-view scientists strike out in the way they have.