Seven Answers to Climate Contrarian Nonsense

This article presents and debunks myths about climate change.

Evidence for human interference with Earth’s climate continues to accumulate

By John Rennie, Scientific American, November 30, 2009

“On November 18, U.S. Sen. James R. Inhofe (R–Okla.) took the floor of the Senate and proclaimed 2009 to be “The Year of the Skeptic.” Had the senator’s speech marked a new commitment to dispassionate, rational inquiry, a respect for scientific thought and a well-grounded doubt in ghosts, astrology, creationism and homeopathy, it might have been cause for cheer. But Inhofe had a more narrow definition of skeptic in mind: he meant “standing up and exposing … the costs and the hysteria behind global warming alarmism.”

“Within the community of scientists and others concerned about anthropogenic climate change, those whom Inhofe calls skeptics are more commonly termed contrarians, naysayers and denialists. Not everyone who questions climate change science fits that description, of course—some people are genuinely unaware of the facts or honestly disagree about their interpretation. What distinguishes the true naysayers is an unwavering dedication to denying the need for action on the problem, often with weak and long-disproved arguments about supposed weaknesses in the science behind global warming.

“What follows is only a partial list of the contrarians’ bad arguments and some brief rebuttals of them.

“Claim 1: Anthropogenic CO2 can’t be changing climate, because CO2 is a trace gas in the atmosphere and the amount produced by humans is dwarfed by the amount from volcanoes and other natural sources.

“Although CO2 makes up only 0.04 percent of the atmosphere, that says nothing about its significance in climate dynamics. Even at that low concentration, CO2 absorbs infrared radiation and acts as a greenhouse gas … Svante Arrhenius … in 1896 … /estimated/ the impact of CO2 on the climate … concluded that doubling its concentration might cause almost 6 degrees Celsius of warming.

“Contrary to the contrarians, human activity is by far the largest contributor to the observed increase in atmospheric CO2. According to the U.S. Geological Survey, anthropogenic CO2 amounts to about 30 billion tons annually—more than 130 times as much as volcanoes produce. True, 95 percent of the releases of CO2 to the atmosphere are natural, but natural processes such as plant growth and absorption into the oceans pull the gas back out of the atmosphere and almost precisely offset them, leaving the human additions as a net surplus.

“Claim 2: The alleged “hockey stick” graph of temperatures over the past 1,600 years has been disproved. It doesn’t even acknowledge the existence of a “medieval warm period” around 1000 A.D. that was hotter than today is. Therefore, global warming is a myth.

“It is hard to know which is greater: contrarians’ overstatement of the flaws in the historical temperature reconstruction from 1998 by Michael E. Mann and his colleagues, or the ultimate insignificance of their argument to the case for climate change.

“There is not simply one hockey-stick reconstruction of historical temperatures using one set of proxy data. Similar evidence for sharply increasing temperatures over the past couple of centuries has turned up independently while looking at ice cores, tree rings and other proxies for direct measurements, from many locations. Notwithstanding their differences, they corroborate that the earth has been getting sharply warmer. (italics mine)

“A 2006 National Research Council review of the evidence concluded ‘with a high level of confidence that global mean surface temperature was higher during the last few decades of the 20th century than during any comparable period during the preceding four centuries’…

“But hypothetically, even if the hockey stick was busted… what of it? The case for anthropogenic global warming originally came from studies of climate mechanics, not from reconstructions of past temperatures seeking a cause. Warnings about current warming trends came out years before Mann’s hockey stick graph. Even if the world were incontrovertibly warmer 1,000 years ago, it would not change the fact that the recent rapid rise in CO2 explains the current episode of warming more credibly than any natural factor does—and that no natural factor seems poised to offset further warming in the years ahead.”

“Claim 3: Global warming stopped a decade ago; the earth has been cooling since then.

Anyone with even a glancing familiarity with statistics should be able to spot the weaknesses of that argument. Given the extended duration of the warming trend, the expected (and observed) variations in the rate of increase and the range of uncertainties in the temperature measurements and forecasts, a decade’s worth of mild interruption is too small a deviation to prove a break in the pattern.

“Claim 4: The sun or cosmic rays are much more likely to be the real causes of global warming. After all, Mars is warming up, too.

“Astronomical phenomena are obvious natural factors to consider when trying to understand climate … Climatologists, therefore, do take them into account in their models. But in defiance of the naysayers who want to chalk the recent warming up to natural cycles, there is insufficient evidence that enough extra solar energy is reaching our planet to account for the observed rise in global temperatures.

“The IPCC notes that between 1750 and 2005, the radiative forcing from the sun increased by 0.12 watts/square-meter—less than a tenth of the net … from human activities.

“Claim 5: Climatologists conspire to hide the truth about global warming by locking away their data. Their so-called “consensus” on global warming is scientifically irrelevant because science isn’t settled by popularity.

“It is virtually impossible to disprove accusations of giant global conspiracies to those already convinced of them (can anyone prove that the Freemasons and the Roswell aliens aren’t involved, too?). /However/ the magnitude of this hypothetical conspiracy would need to encompass many thousands of uncontroversial publications and respected scientists from around the world, stretching back through Arrhenius and Tyndall for almost 150 years. (See this feature on “Carbon Dioxide and Climate,” by Gilbert N. Plass, from Scientific American in July 1959.) It is also one so powerful that it has co-opted the official positions of dozens of scientific organizations including the U.S. National Academy of Sciences, the Royal Society, the American Association for the Advancement of Science, the American Geophysical Union, the American Institute of Physics and the American Meteorological Society.

“Claim 6: Climatologists have a vested interest in raising the alarm because it brings them money and prestige.

“If climate scientists are angling for more money by hyping fears of climate change, they are not doing so very effectively. According to a 2006 Government Accountability Office study, between 1993 and 2004, U.S. federal spending on climate change rose from $3.3 billion to $5.1 billion—a 55 percent increase. (Total federal nondefense spending on research in 2004 exceeded $50 billion.) However, the research share of that money fell from 56 percent to 39 percent: most of it went to energy conservation projects and other technology programs. Climatologists’ funding therefore stayed almost flat while others, including those in industry, benefited handsomely.

“Claim 7: Technological fixes, such as inventing energy sources that don’t produce CO2 or geoengineering the climate, would be more affordable, prudent ways to address climate change than reducing our carbon footprint.

“… critics of standard policy responses to climate change often seem to imply that environmentalists are obsessed with regulatory reductions in CO2 emissions and uninterested in technological solutions. That interpretation is at best bizarre: technological innovations in energy efficiency, conservation and production are exactly what caps or levies on CO2 are meant to encourage.”