In the ongoing wake of Climategate, hockey-stick statistics, and uncooperative temperature trends, the atmospheric tension surrounding global warming continues to hover in the air. The drama, in fact, calls to mind those real-life murder mysteries on TV. In those investigative report shows, we're presented with the forensics and myriad facts, including interviews with detectives, family members, witnesses -- even face-to-face confrontations with the defendants themselves.
And, many times, when the convicted defendant is interviewed, he will say something like, "From the very beginning, the cops suspected me and never looked anywhere else. Anything they found that pointed to me as the guilty party, they took seriously; anything that pointed to someone else, they dismissed."
When this kind of a statement comes from someone sitting behind bars, the viewer is understandably suspicious. After all, doesn't it make sense that the defendant would say anything to win an appeal or release? This, of course, may be true -- that he'd say anything -- but what if what he says actually is true?
Whether it's really true or not comes down to three things: the evidence itself, the person who interprets the evidence, and the actual interpretation of the evidence. At any one point, or combination of points, something could go wrong. For example, an interpreter who is experienced, multi-degreed, highly-skilled, and, to top it off, very popular could be viewed as someone who never makes mistakes; therefore, his or her word is sacrosanct.
Ultimately, then, the evidence is overshadowed by its interpretation.
The analogy to climate-science investigation should be obvious. All scientists have the same data (evidence) to interpret. But, as in crime-scene investigation, there are three key points regarding climate-change evidence:
•The evidence itself,
•How the evidence is interpreted and used, and
•The credibility and believability of the person using and conveying the evidence.
For instance, climate-change temperature evidence exists in several forms, including direct satellite and thermometer readings and ancient proxies (indirect monitors such as historical records, tree-ring analysis, and ice-core measurements).
Satellites give accurate temperature readings for layers of the troposphere (roughly the lowest seven miles of the atmosphere) back to 1979, when the orbiting thermal probes became operational. Thermometer records give rather accurate readings back to about 1850. The proxy data give an understanding of past temperatures back to a range of thousands to hundreds of thousands of years. The accuracy of such data depends on the type of proxy, with historic and tree-ring data being much less accurate than, say, ice-core measurements. Besides, records from history and trees take us back only a few thousand years. It's ice cores that take us hundreds of thousands of years into the past.
In the late 1950s, careful monitoring of atmospheric carbon dioxide (CO2) concentrations was started by Dr. David Keeling at Mauna Loa, Hawaii. Such measurements have indicated a sharp rise in global CO2 values from about 310 ppm at the start to over 390 ppm today. Scientists have wondered what such an increase, apparently from anthropogenic carbon emissions, is doing to the earth's atmosphere, since the rise in CO2 levels seems to trace the general rise in worldwide average temperatures.
So, historically, the focus has been on the culprit, CO2, and its "crime," increased terrestrial temperatures.
For the "Humans did it!" global-warming plaintiffs, one of the star lawyers is former Vice President Al Gore, who has claimed on behalf of his clients that "the earth has a fever and [...] maybe that's a warning of something seriously wrong."
In addition, there's Dr. James Hansen, the popular veteran scientist behind a huge portion of Mr. Gore's outrageous claims. Dr. Hansen, director of NASA's Goddard Institute for Space Studies, defends not only the planet, but also ostensibly children and grandchildren everywhere by urging the arrest of the CO2 culprit at its sordid lair: coal-fired power plants.
Mr. Gore and Dr. Hansen certainly exhibit sincerity regarding their causes -- but sincerity is not a virtue. This may come as a surprise, but politicians, and even scientists, can be sincerely wrong. Unfortunately, in the courtroom of public opinion, both gentlemen are definitely convincing and believable -- two terrific examples of a case where the evidence is overshadowed by its interpretation.
However, it's arguable that considering the enormous and growing number of independent, knowledgeable earth and climate scientists, the wrong perpetrator has been nabbed. When the evidence is evaluated dispassionately, without preconceived notions, and in the context that the real "culprit" has still not been identified (like, heaven forbid, Mother Nature herself), the gavel may finally drop on the truth about climate change.
In the interim, the next time the shocking details of runaway global warming are reported by the mainstream media, remember that the usual suspect -- man-made greenhouse gas -- may indeed be innocent of crimes against the environment.
Anthony J. Sadar is a certified consulting meteorologist and principal author of Environmental Risk Communication: Principles and Practices for Industry (CRC Press/Lewis Publishers, 2000). Albin Sadar is a television writer living in New York City.