Samuel Johnson believed that "Knowledge is of two kinds. We know a subject ourselves, or we know where we can find information upon it." Sadly, for some reason, perhaps involving his having died two centuries before the invention of the Interwebs by Al Gore and Ronald Reagan, Dr. Johnson missed a third and these days most important kind of knowledge: bullshit that Internet commenters believe and will take any opportunity to spew with great vehemence and very little grammar or punctuation.
This past weekend George Will, bow-tied right-wing pundit and poster boy for getting your ass kicked on the elementary school playground, suggested that the recent run of record-setting heat doesn't prove that global warming has occurred or that it stems from human activity. Needless to say, his remarks were greeted in online forums with the kind of calm reasoned argument that has distinguished the Internets from, say, professional wrestling, in that no one involved in this conversation has (yet) been hit with a chair.
Now, I have since the dark days of the Reagan Administration disagreed with every word of George Will's I have ever read or heard uttered, including "and" and "the" (with the exception of his characterization of Donald Trump as a "bloviating ignoramus"), but it pains me to report that at least a portion of his remarks this past weekend weren't completely wrong, at least in a very specific way. A week of hot weather does not prove the validity of global warming, any more than the frigid winter of 2011 proved -- as Fox's newsmorons claimed at the time -- global warming a myth. What does prove the validity of global warming are data that demonstrate -- unequivocally -- that over the past 130 years the Earth's surface has increased in average temperature by .6ºC; that most of the hottest recorded years have come in the past two decades; and that most of the warming in the last 50 years comes from increases in man-made carbon dioxide and methane in the atmosphere.
How do we know this stuff? Climate scientists -- people who are trained to sift through and interpret the data -- tell us so -- 97 percent of them believe by virtue of the statistical evidence that global warming is a fact, and that it is man-made. This is an extraordinary unanimity, given scientists' unfortunate habit of thinking for themselves -- you probably wouldn't find that 97 percent of scientists disbelieve in leprechauns. No trumped-up scandal, no amount of oil-industry propaganda, no ignorant "my opinion's just as good as theirs" bullshit and no "Wow, it's cold today; guess global warming's a myth" non sequiturs can even begin to have the kind of probative force that evidence put together and interpreted by the careful processes of science does.
I don't know climate science, and I have no ability or right to interpret the data -- and neither does George Will, whose offhand comment about how hot it was in central Illinois when he was a boy proves nothing. You know who does have the right and ability to understand what is happening to our one and only earth? Those thousands of climatologists working away at the data, who will never get to opine on a Sunday news show, and who are too busy doing useful and important work to blither on Internet comments threads. So yes, George Will in a very small way was right, but in a much larger way, in the self-inflating assumption that he knows as much as those who spend their lives studying these matters, he has arrogantly assumed that folksy platitudes and "common sense" can equal the power that science has to discover the truth. The next time you get a staph infection, try reading it passages from Will Rogers and Jeff Foxworthy; if you have an iPad, please leave it to me in your will.