Exclusive to STR
August 6, 2007
On February 9, Boston Globe columnist Ellen Goodman announced that '. . . we're at a point where global warming is impossible to deny. Let's just say that global warming deniers are now on a par with Holocaust deniers . . . .' . She has a point. The available data does point conclusively to the fact that things have been getting hotter, at least over the past century . But I suspect that Goodman wasn't only referring the last century's warming trend. No, judging by the fact that she bragged about her new 'environmentally friendly, compact fluorescent light bulb,' and 'the Prius in [her] driveway,' I think it's safe to assume that she was proclaiming the factual existence of a historically unprecedented warming trend caused by human emissions which must be stopped, or else .
So why has Unstoppable Global Warming Every 1,500 Years, a book by Fred Singer  and Dennis Avery  not been relocated to the World War II History section? After all, it boldly claims that global warming is simply part of a natural cycle! And after Denmark 's firsthand experience in fighting off the Nazis, surely Henrik Svensmark's new book, Chilling Stars, should have put him in hot water at the Danish Space Research Institute. He thinks that cosmic rays from exploding stars are a main driver of climate change. But Singer and Svensmark are experienced atmospheric scientists, while Goodman is a journalist with no expertise in the area, representing the self-proclaimed consensus view. It's obviously not true that absolutely everyone agrees about global warming, but are these, and other, skeptics just being stubborn Holocaust deniers?
We've all heard that greenhouse gases like CO2, water vapor, methane, and ozone warm the atmosphere. When heat radiates from the Earth's surface, these gases absorb it and reflect it back, instead of letting it escape into space. Theoretically, increases in greenhouse gas should lead to a hotter planet, and since the Industrial Revolution, human activity has contributed significantly to a 30% increase in atmospheric levels of CO2 . If the increase in greenhouse gas can truly explain the noticeable global climate change we have observed, then Ellen Goodman's light bulb would illustrate an admirable gesture in the fight to avert catastrophe. But how sure are we that greenhouse gases are the real culprits? Is there any evidence that would lead a serious person to question the explanation we seem to be hearing from almost everyone? I think so.
During a speech at Carleton University , geology professor Tim Patterson showed that 'There is no statistical correlation between the levels of carbon dioxide in the atmosphere through the last 500 million years and the temperature record in this interval' . Patterson points out that historically, 'temperature [goes] up first'with CO2 coming up later. This correlation indicates that, as one might expect, as temperatures warm biological productivity increases resulting in more CO2 in the atmosphere [sic]' . In other words, rising CO2 levels don't typically cause climate change; climate change causes rising CO2 levels.
But even if CO2 hasn't caused changes in the past, couldn't it still be responsible for the recent warming trend? Astrophysicists Sally Baliunas and Willie Soon  don't think so. They believe that the sun has more to do with our climate's warming than CO2. The astronomers among us will know that the sun goes through a magnetic cycle which runs in approximately eleven year intervals. During this cycle, the amount of energy emitted from the sun varies, along with the strength of the sun's magnetic field. Scientists have discovered that the sun's cycle is not completely uniform; some cycles go on for longer than others, resulting in different levels of light intensity and magnetic forces. 
Baliunas and Soon explain that 'the question [of] how the sun affects the climate is unresolved' [] but some studies suggest that differences in the energy output and magnetism of the sun can have effects on cloud coverage, atmospheric chemistry, and circulation patterns, all of which have very significant impacts on global climate []. Furthermore, their data shows that global temperatures seem to have a much closer relationship with solar variability than with atmospheric CO2 levels [].
Does this imply that we should simply dismiss the work of the many hundreds of scientists saying that humans cause global warming? Of course not. We would be guilty of a double standard if we said that the plausibility of some alternative theory conclusively disproves the mainstream view. And even if the sun really does play the most important role in determining global climate, we can't conclude that greenhouse gas has been completely uninvolved in causing the current warming trend; we have every reason to believe that it plays at least some role. But it may be wise to reconsider the way we think about the global warming debate. It doesn't seem like the scientists who question our responsibility for global warming are indefensible skeptics who refuse to acknowledge what is obviously true. Rather, it appears that there is still a lot of research to be done before we can consider this case to be completely closed. Perhaps people like Ellen Goodman should avoid name-calling until they've heard all the evidence.
: Goodman, E. (2007, February 9). No Change in Political Climate. The Boston Globe. Retrieved August 5, 2007 from: http://www.boston.com/news/globe/editorial_opinion/oped/articles/2007/02....
: See for example, Hansen, J., Ruedy, R., Sato, M., & Lo, K. (2006, January 12). GISS Surface Temperature Analysis. Retrieved August 5, 2007 from: http://data.giss.nasa.gov/gistemp/2005/.
: Goodman, op cit.
: Founder of the Science and Environmental Policy Project and professor of environmental science at the University of Virginia .
: Director of the Center for Global Food Issues.
: Barbalace, R. C. (2006, November 7). CO2 Pollution and Global Warming: When does carbon dioxide become a pollutant? Retrieved August 5, 2007 from: http://environmentalchemistry.com/yogi/environmental/200611CO2globalwarm....
: Patterson, T. (2005, January 1). The Geologic Record and Climate Change. Retrieved August 5, 2007 from: http://www.tcsdaily.com/article.aspx?id=010405M.
: Both of the Solar, Stellar and Planetary Sciences Division of the Harvard-Smithsonian Center for Astrophysics.
: See Patterson, op cit; Baliunas, S., & Soon, W. (1999, October 20). Solar Variability and Global Climate Change. Retrieved August 5, 2007 from: http://oldfraser.lexi.net/publications/books/g_warming/solar.html.
: Baliunas, S., & Soon, W., op cit.