Climate Alarmists Warm It Up
They overcook the evidence of 2014 to support their shaky predictions of global warming.
By Rupert Darwall
The year 2014 had scarcely expired before being declared the warmest year on record. First off was the Japan Meteorological Agency. The year 2014 surpassed 1998 to set a new record by all of five one hundredths of one degree Centigrade, according to the agency?s preliminary numbers. Then Britain?s Met Office announced that 2014 was the warmest year in the 355 years of the Central England Temperature series.
Each year, global-warming adherents anticipate an El Niño (a strong warming phase in the Pacific) as the physical manifestation of global warming?s Second Coming to herald the end of the barren years of flat-lining global temperatures. The Center for American Progress?s Joe Romm called the 2014 record doubly impressive. As Romm noted, ?We?re still waiting for the start of El Niño? but got a temperature record nonetheless.
After years of climate-change prognosticators? pointing to extreme weather events ? Arctic (but not Antarctic) sea-ice extent and, as they claim, excess heat disappearing into the ocean ? as evidence of global warming, it is scientifically healthy that attention is focusing back on trends in global surface and atmospheric temperature, as the theory is that global warming should drive climate change. Indeed, the Met Office press release belies alarmist notions of ?climate disruption,? ?climate breakdown,? and the other terms trotted out from the shop-soiled lexicon of alarmism.
Despite seeing a record-breaking year overall, Britain had no major heat waves, and no new monthly records were set in 2014. Instead, each month was consistently warm, only one having below-average temperatures, and the year seeing the lowest number of frosts since 1961. Similarly with rainfall: Although 2014 was one of the 20 wettest years since 1766, no individual region had its wettest year on record. After a stormy January and February in Britain, the rest of the year was ?relatively quiet,? as the Met Office describes it.
This isn?t part of the narrative being spun by Naomi Oreskes, Harvard professor of the history of science. Previewing the hottest-year-on-record announcements, Oreskes wrote in the New York Times last week that we were underreacting to the reality of dangerous climate change ?now unfolding before our eyes.? The burden of proof should be lowered, Oreskes argued, but her excursion into statistical methodology to buttress this contention was widely panned (here, here, and here).
Most jaw-dropping was Oreskes?s claim that climate change is happening ?faster than scientists predicted.? This is flat-out untrue. A 2013 commentary co-authored by Francis Zwiers, an elected member of the IPCC Bureau and former IPCC lead coordinating author, found that recent observed global warming was significantly less than the surface trend simulated by climate models. In the 15 years to 2012, the observed trend of 0.05 degrees Centigrade per decade ? not significantly different from zero, according to the authors ? was more than four times smaller than the averaged simulated trend of 20 climate models used by the IPCC. Since the turn of the century, the 15-year running trend in observed temperature has fallen back to the 1900?2012 trend, an increase of around seven tenths of one degree Centigrade per century. For Oreskes?s claim to be valid, scientists would have had to be expecting global cooling.
In science, models are used to produce predictions that can be tested against nature and thereby advance scientific knowledge. On this basis, the clear inference of the disagreement between climate-model simulations and observations over the past two decades is that scientists? current understanding of the climate system is faulty. Climate science is not normal science: It has become the leading branch of global therapeutics. Climate-model outputs are used as a tool to win the political battle for policies believed necessary to save a dying planet.
Arguing for a relaxation of confidence levels (misdescribed by Oreskes the polemicist as burden of proof) to justify such policies, Oreskes the historian misattributes the widely used 95 percent confidence level to R. A. Fisher, the British statistician. Biologist Richard Dawkins once described Fisher, possessed of a towering intellect, as the father of modern statistics and, for his work in genetics, Darwin?s greatest 20th-century successor. Rather than the 95 percent confidence level, to Fisher belongs the credit of formulating the null-hypothesis test: For there to be a relationship between two variables, it must first be demonstrated that the null hypothesis ? that the two variables are independent of each other ? is false. As Fisher put it, every experiment may be said to exist only in order to give the facts a chance of disproving the null hypothesis.
The null hypothesis is widely used across the physical and social sciences, but not by the IPCC. In the approximately 1,500 pages of the IPCC fifth assessment report (2013) on the physical basis of climate change, it merited three paragraphs. Whether global temperatures rise by up to 4.8 degrees Centigrade by the end of century, as the IPCC believes, or, in line with 1900?2012 trends, rise by 0.7 degrees Centigrade by the century?s end, there will continue to be years that set new temperature records. However, this would tell us next to nothing about whether such events portend catastrophe or are essentially harmless.
There is a non-temperature trend that should worry alarmists. Since March 2001, Gallup?s environment poll has surveyed voters annually on the seriousness of global warming. In the first years of the century, the percentage who said global warming was exaggerated was generally in the low 30s (2004 saw a spike to 38 percent). The percentage then rose in the run-up to the December 2009 Copenhagen climate conference and peaked three months later at 48 percent. Since then, the percentage has slipped back to the low 40s ? the skeptics, as they might be called, gaining ten points on the prior decade.
With the intensifying drumbeat of alarm and exaggeration anticipating this year?s Paris climate conference in December, climate-change alarmists face a conundrum: The more they act true to form, the more voters become skeptical and, in the United States, the greater the political incentives for Republicans to block climate-change policies. As yet, the alarmists don?t seem to have gotten the message.
? Rupert Darwall is the author of The Age of Global Warming: A History (Quartet, 2013).