A Bad Year for Climate Alarmists

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A version appeared in the Calgary Herald, November 7, 2003

This has been a very bad year for climate alarmists. On the threshold of worldwide enactment of the Kyoto Protocol, the Russians are saying “nyet,” and scientists around the world are busy ripping the rug out from under alarmist climate predictions.

First the science. Climate alarmists advocating Kyoto have long built their case on the claim that recently observed warming is historically unusual, and is therefore likely to be caused by human action. But since nobody was taking the Earth’s temperature a thousand years ago, the claim that humans are changing the climate rests on a relatively simplistic theory about how the climate works, and on comparisons of recent temperatures with those derived from “proxy” indicators of past temperature, such as tree rings, and coral shell characteristics. The most alarmist “reconstruction” of past temperatures was developed by a researcher named Michael Mann, and his 1998 temperature reconstruction (shaped something like a hockey stick laying flat with its blade in the air), which led the United Nations Climate Panel to claim “that the 1990s has been the warmest decade, and 1998 the warmest year of the millennium” for the Northern Hemisphere.

But skeptical scientists have doubted this representation of past climate for decades. Many scientists studying ancient climates found evidence that past ages had climate shifts to temperatures considerably warmer than today, shifts that happened more quickly than recently observed climate change. The most recent warm period scientists have identified is the Medieval Warm Period, which happened about 1000 years ago. The most recent cold snap scientists have identified is called the Little Ice Age, which happened from about 1300 to 1900 AD. To support the hockey stick against challengers, alarmists have worked hard to classify both the Medieval Warm Period and the Little Ice Age as “local phenomena,” and thus, not meaningful indicators of global climate.

But two recent studies have badly damaged the hockey stick. The first study, by Harvard Astrophysicist Sallie Baliunas, and her colleague Willie Soon, reviewed more than 200 climate studies, and confirms the that both the Medieval Warm Period and the Little Ice Age were global, not regional, phenomena. As Baliunas explains, “For a long time, researchers have possessed anecdotal evidence supporting the existence of these climate extremes. For example, the Vikings established colonies in Greenland at the beginning of the second millennium that died out several hundred years later when the climate turned colder. And in England, vineyards had flourished during the medieval warmth. Now, we have an accumulation of objective data to back up these cultural indicators.”

The most recent study to crack the hockey stick was, appropriately enough, by Canadian researchers Ross McKitrick and Steve McIntyre. The two Canadians obtained the very same data sets and methods ostensibly used by Mann in constructing the hockey stick, and ran an audit on the data and calculations. Their findings were shocking. The Mann dataset, they found, contained numerous errors in data handling. Critical data sets were truncated or extrapolated unreasonably; some of the data was obsolete, there were errors where temperature records were erroneously linked to the wrong geographical location, and there were errors in various calculation methods.

McKitrick and McIntyre fixed the errors, re-ran the calculations using Mann’s own methods, and lo and behold, no more hockey stick. Instead, the repaired climate reconstruction looks a bit more like the side view of a pie plate, with high global temperatures seen around 1000 years ago, a dip into a cold spell till around 1900, and a return to warmer temperatures over the last 100 years.

Now to the politics. For the Kyoto Protocol to actually come into force as a binding international treaty, it has to be signed by 55 countries accounting for at least 55 percent of global emissions in 1990. Canada’s ratification of the Kyoto Protocol brought treaty supporters close enough to the target that only one more country was needed: Russia. But the great bear is focused on putting its economic house in order, and furthermore, has scientists who are far more skeptical about climate change than their colleagues in the West. So when Russian President Vladimir Putin, backed by prestigious scientists from the Russian Academy of Sciences, came out against the treaty at the recent World Climate Change Conference in Moscow, there was a collective groan of anguish among climate alarmists, who are now desperate to get the treaty into effect before still other studies in the wings continue to rip the underpinnings out of their alarmist scenarios.

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