As the Earth's climate continues to change at an accelerating rate, the juggling and magical thinking and outright hypocrisy of climate change deniers continues to accelerate as well. While there are many examples of the remarkable ability of deniers to hold onto mutually contradictory beliefs and ideas, here are four well-worn arguments regularly put forward by deniers in public forums despite the fact that they've all been debunked (over and over and over) by scientists:
Deniers claim that climate models are bad, but they're happy to rely on far less reliable economic models to argue against taking action: One of the classic arguments of climate deniers is that the multitude of climate models is bad. Yet at the very same time, they promote the conclusions of a couple of economic models that say that doing anything about climate change will bankrupt the global economy. In fact, climate models are far superior to economic models. Climate models are far more rigorously tested, far more firmly based in physical reality, and far more unanimous in their projections than the economic models that have been applied to the problem of climate change. Indeed, you can find one set of economic models that says that mitigating greenhouse gases will be relatively cheap and another set that say it will be extremely expensive. You cannot find a state-of-the-art climate model that says the climate won't change with growing greenhouse gas concentrations.
In addition, none of the economic models that look at the costs of reducing greenhouse gas emissions addresses the other, critical side of the economic argument — the vast and exponentially increasing costs to society of doing nothing. What's the economic cost, for example, of losing California's snowpack or a species of plant or animal? What's the economic cost of a one-month acceleration in the timing of runoff in major rivers in the western U.S.? What's the economic cost of rising sea level or growing heat stress or more intense storms or changing distributions of plants and animals — all impacts that are certainly going to occur? Perhaps we can compute some dollar values for some of these things, but we haven't yet, and so no complete estimates are included in cost comparisons. In other words, climate deniers and those who argue against action say that the cure (reducing emissions) is worse that the disease (the impacts of climate change), when we have contradictory estimates of the costs of the cure and no comprehensive estimate of the costs of the disease.
Government action is anathema; the answer is let the free market work (oh, but we can't have markets for carbon): Some climate deniers argue that climate science is wrong because they're driven by a strict ideology that opposes (rightly or wrongly) growing government regulation, while they simultaneously believe that economic free-market approaches are the only way to handle public policy problems like pollution. This is free-market fundamentalism, and while one might agree or disagree with that philosophy, it has no bearing on the validity of climate science. Yet these same free-market ideologues reject market solutions and strategies to control greenhouse gases, such as carbon markets, trading systems, and classic tax programs that would internalize externalities. Thus we have the odd situation where the Federal government is now being forced to regulate greenhouse gases through the USEPA and potentially awkward governmental mechanisms because climate skeptics and deniers in Congress failed to adopt their own preferred market and economic solutions.
Deniers argue that comprehensive observational data on the world's changing climate are wrong, but then point to cold weather in this or that location to argue that the world cannot be warming: While the public may not fully understand the difference between climate and weather, or understand how the world could be warming while it's cold outside, most well-known climate deniers fully understand these distinctions — they just choose to ignore them in order to make false arguments to and score points with the public and gullible policymakers. Cherry-picking selected data that supports a particular point (i.e., it's cold today), while hiding or ignoring more data that points in exactly the opposite direction (i.e., global average temperatures are rising), is bad science and it leads to bad policy. Just last week Glenn Beck pointed to a snowstorm in Minneapolis as proof that global warming isn't happening. He knows better, but his audience may not. Another example was the effort by the Bush Administration to argue that they were taking action on climate change and that the US was doing more and better than European countries, when in fact, the White House cherry-picked the data that showed their position in the most favorable light. All the data, analyzed together, showed exactly the opposite conclusion.
Oh, and by the way, it looks like 2010 will be, globally, one of the warmest years on record, after a long series of increasingly hot years. And the entire decade from 2001-2010 is undoubtedly the warmest 10-year period since the beginning of comprehensive weather records in 1850.
Deniers seize on a few minor mistakes in the IPCC report to claim its overall conclusions are invalid; but then use massively flawed scientific arguments to dispute real climate science: The Intergovernmental Panel on Climate Change (IPCC) has produced a series of reports over the past decade or more, thousands of pages in length, summarizing the scientific understanding from tens of thousands of peer-reviewed reports. It is not new science; it is a comprehensive and clear summary of the science. A few minor errors have been made (and corrected), but none of these affect the conclusions, despite the fact that they've been seized upon by climate deniers as evidence that the whole thing is wrong. Yet climate deniers use deeply flawed scientific arguments that have been debunked over and over or have little or no basis in reality. This is a double standard: it is incumbent upon scientists to produce their best work, to acknowledge mistakes, and to correct them. It is time to hold climate deniers to the same standard, rather than letting them repeat long debunked falsehoods.