The appearance of an editorial in the far-right-leaning Washington Times challenging the reality of anthropogenic climate change is not particularly interesting. What is worth looking at is the width of the gap between the research cited by the editorialist and what the research is actually all about.
The editorial, which ran under the headline “Nero was hotter than Al Gore,” argues that a new paper in the Proceedings of the National Academy of Sciences finds the Earth was warmer in Roman times than it is today. Even if true, this would mean little, unless the ancient anomalously warm period was exceptionally long. But it certainly would constitute a convincing counterargument to the notion that the recent decade has been the warmest in human history.
The alarmists must imagine that 50 years before the birth of Christ, men like Julius Caesar spent their summers strolling the streets of Rome wearing sweaters to guard against catching a chill – instead of abandoning the sweltering capital in favor of temperate seaside villas. A study published in the March 8 edition of the Proceedings of the National Academy of Science casts further doubt on the warmist premise by concluding that the sun beat down more harshly on the Caesars than it did on anyone else in the past 2,000 years.
The piece concludes by making reference to other, unspecified studies that “confirm the existence of Roman and Medieval warming periods, where no source of “greenhouse gases” existed aside from the horses and cows of the time.”
…we encourage our senators to stab their daggers into the heart of cap-and-trade and all other legislation being promoted in the name of climate-change fiction.
The PNAS paper in question, “Two millennia of North Atlantic seasonality and implications for Norse colonies,” doesn’t support that argument. It is essentially a look at what temperatures in the North Atlantic, as recorded by the ratio of oxygen isotopes in sea shells in a bay in northwest Iceland (not Rome, or anywhere else for that matter), were between the 4th century B.C. and the 17th century A.D. The research results have much to say about the reliability of historical documents from the period, and should prove most useful from anthropological point of view. They say lots of about natural variability in one corner of the world. For example:
The high-resolution seasonal temperature record derived from the mollusk 18O values, in contrast, shows a clear increase in temperatures after A.D. 1400, which may demonstrate that there was a more localized climate influence on Iceland. (Emphasis mine.)
I asked the asked the paper’s lead author, Bill Patterson of the University of Saskatchewan, what he thought of the editorial. His initial response wasted few keystrokes:
Clearly the editor does not understand climate science!
His second response was a bit more detailed:
Natural climate change and Global Warming are two completely different beasts, though they may enhance or counter one another at times. We really have no way of knowing the influence of each on or most recent climate variability.
Patterson has run across this problem before. In an editorial of his own written a couple of years back, he discussed the myriad gaps in knowledge and the challenge posed by the resulting levels of uncertainty about climate change. He also has this to say about the suggestion that the science supports the Washington Times‘ laissez-faire position on rising temperatures:
Until we gain a better understanding of the carbon cycling, climate change and global warming, should we moderate our production of greenhouse gases? Absolutely! A complete understanding of the carbon cycle will not happen soon and this is no excuse to run roughshod over the atmosphere.
One does not expect every journalist to track down every lead author of every paper tha informs anything the journalist writes. But it would help to actually read a paper before citing it, and it further helps to understand the basic science at hand before challenging the position of almost every single expert in that field. There are dozens of examples of similar errors — bloggers confusing U.S. temperature records with global records, the canard about the Medieval Warming Period of Northern Europe being representative of the planet as a whole, and so on. They call it GLOBAL warming for a reason.
Patterson, W., Dietrich, K., Holmden, C., & Andrews, J. (2010). Two millennia of North Atlantic seasonality and implications for Norse colonies Proceedings of the National Academy of Sciences, 107 (12), 5306-5310 DOI: 10.1073/pnas.0902522107