If you had to stretch reality into an unrecognizable shape in order to maintain a stance, why would you do it?
The movement of global warming denial has left me pondering that question. Two recent episodes in particular have brought that question to the forefront of my mind.
The first is the decision by the people who deny the existence of global warming to assert the opposite: that since 1998, the world has been undergoing global cooling. Take the conservative corporate National Review Online earlier this year:
Mother Nature refuses to cooperate. Earth’s temperatures continue a chilling trend that began eleven years ago. As global cooling accelerates, global-warmists kick, scream, and push their pet theory — just like little kids who cover their ears and stomp their feet when older children tell them not to bother waiting up for Santa Claus on Christmas Eve.
You can find this stuff all over the place: claims that the Earth is undergoing a “chilling trend” of “global cooling.” A month ago I demonstrated graphically how to create such a claim: carefully pick two dots, draw a line, and ignore everything else. To reprise, here’s data from NASA’s Goddard Institute:
See the little green line? Global Cooling! How carefully do you have to pick your dots to make “global cooling” appear? Very carefully indeed. This line connects 1998 and 2008. But if you connect 1998 and 2007, you’ll get a flat line. And if you go back to 1997, you get global warming all over again. 1998 is a very important year for global warming denial, since it is an outlier and therefore allows all sorts of line drawing that wouldn’t otherwise be possible. But no matter how many little green lines you draw, you just can’t counter the larger trend of global warming.
I’m not just saying that, either. The Associated Press just finished conducting an interesting test in which they gave global temperature trend data to four different statisticians. In order to remove the possibility of biased judging, the AP didn’t tell the statisticians it was temperature data; they removed temperature unit labels, just leaving the numbers themselves in a trend over time. The results of this “blind” analysis?
Statisticians who analyzed the data found a distinct decades-long upward trend in the numbers, but could not find a significant drop in the past 10 years in either data set. The ups and downs during the last decade repeat random variability in data as far back as 1880.
This isn’t the only episode in which global warming deniers have cherry-picked data in order to claim “global cooling.” Before the National Review hopped on the “global cooling” bandwagon, retired Professor Don J. Easterbrook of Western Washington University claimed another “global cooling period” in this graph:
Notice how Don J. Easterbook has placed his nice, neat blue lines to create a “global cooling” period from right about at 1944 to right about at 1978? Those aren’t randomly-picked years. 1944 was an especially warm year compared to the years that followed, and 1978 was a relatively cool year compared to the years that followed. Just as global warming deniers have cherry-picked the years 1998 and 2008 to create “global cooling” in this decade, Easterbrook cherry-picked data points to create “global cooling” in a prior period. Return again with me to NASA Goddard Institute data, and we’ll put Easterbrook’s “global cooling” period in context:
If Easterbrook hadn’t picked just the right year, he wouldn’t have been able to refer to such a “global cooling” period. The 50s, 60s and 70s were a relatively flat period sitting below a few years of warmer temperatures in the 40s, but well above the temperatures of the 30s, and well above the 20s, and well above the 10s, and well above the aughts, and well above the 1890s, and well above the 1880s. The most that Easterbrook in full context can refer to is a brief pause in warming, not a period of global cooling.
Whenever you hear someone referring to a “global cooling” period, especially if they throw in references to climatologists as screaming and kicking toddlers, pay close attention to the years they choose. I bet you dollars to donuts that there’s a whole lot of cherry-picking going on.
I still can’t answer the question I started with: If you had to stretch reality into an unrecognizable shape in order to maintain a stance, why would you do it? Motivations, unlike global temperatures, are unmeasurable. When you catch someone mangling the data like this in the future, ask why. Then watch for the reaction.