Climategate, Copenhagen, Snowmageddon in the nation’s capital, the EPA ruling that CO2endangers us all, and Senate Republicans pushing for a global-warming tax. Has it been a great run-up to Earth Day, or what?
Never has a public-policy agenda been pursued with so little regard for scientific fact or public opinion. In March, 48 percent of Americans agreed that global warming, while real, is exaggerated. When Gallup first asked this question in 1997, only 31 percent thought the threat exaggerated.
Despite this shift in sentiment, Sens. Lindsey Graham (R., S.C.) and John Kerry (D., Mass.) and President Obama insist upon ramming a new global-warming tax (called a “fee”) through the Senate. The bill is slated to be introduced next week, and vulnerable Democrats — weary already from the pugilistic health-care debate — are fleeing the legislation in droves.
And for the measure’s primary backers, the backdrop of recent developments on the climate-science landscape could not possibly be less fortuitous.
Climategate revealed that a small but influential coterie of climate scientists did everything they could to present messy global-warming data as a “nice tidy story,” meticulously crafted to “hide the decline” in tree-ring-based temperatures. (I use quotes because those are the words of the warming-alarmist scientists themselves.)
The fact is that tree rings are pretty poor indicators of annual warmth, especially in recent years. Dendrochronologists call this the “divergence” problem (cynics call it other names). Phil Jones, the central figure in Climategate, actually eliminated the “divergence” rather than “hiding the decline.”
The amount of “explained variance” or statistical correlation between rings and temperatures during the summer growing season tends to run about 40 percent. That means more than half of the temperature changes for a fraction of the year (and even more for the entire year) are unexplained.
The famous “Hockey Stick” temperature history, by Penn State’s Michael Mann, is composed largely of marginally explanatory tree-ring data, which he subjected to a statistical analysis that produces different results depending on what portion of the data is chosen to represent the average condition. If there are 1,000 years of data, and one uses only the last 100 years to calculate the average against which to measure all the other years, that will help to produce an upward-pointing “hockey stick.” Using all of the data to form an average will give a smoother result.
Last week, David Hand, president of the Royal Statistical Society, acknowledged that “the particular technique they used exaggerated the size of the blade at the end of the hockey stick. Had they used an appropriate technique, the size of the blade of the hockey stick would have been smaller. . . . The change in temperature is not as great over the 20th century compared to the past as suggested by the Mann paper.”