Proving that old misunderstandings are not easily resolved, Politico published an anachronistically bad article about climate science yesterday. The piece, by Erika Lovley, began by stating that:
Climate change skeptics on Capitol Hill are quietly watching a growing accumulation of global cooling science and other findings that could signal that the science behind global warming may still be too shaky to warrant cap-and-trade legislation.
First of all, Lovley does not review (or even mention) a single piece of climate research that supports the notion of a “growing accumulation of global cooling science.” Second of all, she bases her entire piece on the arguments of Josef D’Aleo and a section on climate change that he wrote for the 2009 Old Farmer’s Almanac (that bastion of peer-reviewed science!). D’Aleo is co-founder of The Weather Channel and a career meteorologist with a master’s degree in meteorology, but he does not have a doctorate in climatology. Generally speaking, that is an important distinction that all climate reporters should be aware of when choosing sources for their reporting.
There has been a notable trend in global-warming skepticism among meteorologists; it’s unclear exactly why that is, but it has led to some journalistic confusion about the difference between weather (meteorologists’ domain) and climate (Ph.D climate scientists’ domain). And that confusion has abetted some of the misunderstanding about global cooling. Lovley writes that:
Armed with statistics from the Goddard Institute for Space Studies and the National Oceanic and Atmospheric Administration’s National Climate Data Center, D’Aleo reported in the 2009 Old Farmer’s Almanac that the U.S. annual mean temperature has fluctuated for decades and has only risen 0.21 degrees since 1930 — which he says is caused by fluctuating solar activity levels and ocean temperatures, not carbon emissions.
Data from the same source shows that during five of the past seven decades, including this one, average U.S. temperatures have gone down. And the almanac predicted that the next year will see a period of cooling.
Well, yes, the mean temperature in the U.S. has gone up and down over the last century, but it’s global mean temperature that really matters in this debate. Furthermore, if Lovely had called the people behind that data, she would have learned that the scientists at Goddard firmly believe the world is getting warmer. Lovley gets to the Northern Hemisphere, at least, shortly thereafter when she quotes D’Aleo delivering one of the most common, and fairly easily rebutted, arguments in the skeptic’s playbook: “Recent warming has stopped since 1998.”
First, 1998 was an anomalously warm year (due to a particularly strong El Niño effect in the Pacific), so it is not a particularly good baseline for comparison. Second, the statement relies on only one data set (i.e. temperature record), from the Hadley Climate Centre in the U.K.’s Met Office (weather service), which happens to represent the lower end of warming. Other data sets show greater warming since 1998, and although the Hadley Centre data still lists that year as the hottest on record, others agree that 2005 was hottest and that 1998 and 2007 are tied for second place. Finally, the last and perhaps biggest problem with D’Aleo’s statement is that ten years is really too short a time period to show anything useful about climate. (Both Grist and New Scientist have made all of this abundantly clear; and, like Goddard, the Hadley Centre does not dispute the scientific consensus on climate change). The bottom line: in the long run, the Earth as a whole is still getting warmer.
This brings us back to the confusion about weather and climate, and the fact that short-term changes in the former are irrelevant to long-term trends in the latter. Yet every winter, the onset of cold inspires climate skeptics to once again attempt to “debunk” global warming and journalists to once again fall for the maneuver. I reported on that phenomenon in 2007, and New York Times reporter Andrew Revkin covered it in March 2008. Despite journalists’ earnest, and somewhat successful, efforts to move past the basic points that global warming is happening and that human industry is the cause, lingering confusion about the basics of climate science continues to plague public understanding.