NEW YORK (TheStreet) -- "There is no scientific proof that human emissions of carbon dioxide (CO2) are the dominant cause of the minor warming of the Earth's atmosphere over the past 100 years."
That statement is from Senate testimony from Greenpeace co-founder Patrick Moore, a scientist himself, albeit one in the consulting business these days. The United Nations' Intergovernmental Panel on Climate Change would beg to differ. The group earlier this week published the third installment of its Fifth Assessment Report, citing thousands of papers drawing together the work of tens of thousands of scientists in a claim that global warming is largely caused by man-made pollution, most notably carbon dioxide. The latest addition to the report offers recommendations for immediate, worldwide reductions in CO2 emissions in an effort to avoid catastrophic outcomes for the planet.
Moore's views represent those of a great many denialists, whose arguments are an onion with many layers and no substantial core. Further, the fact that he himself is a scientist bolsters the popular notion that the scientific community is deeply divided on this issue. Professional dissent of various stripes is present in any scientific debate, and rightly so, but the consensus among scientists is real, and from a professional view at least, Moore's objections represent a small minority.
Moore takes direct aim at the methodology behind the IPCC findings. Rather than measurable proof, he said, the scientists are relying on computer models, which are only as accurate as their human programmers. "We may think it sophisticated, but we cannot predict the future with a computer model any more than we can make predictions with crystal balls, throwing bones, or by appealing to the gods," he said in his written testimony in February. Moore apparently thinks computer models are useless because they deal in statistical probabilities and require human input of data. On the contrary, computer weather models have proven incredibly useful in predicting tornado and hurricane paths and strength trends, not to mention rains, floods, dry spells and droughts, for at least a generation. The models can give us information we desperately need to improve quality of life and to save lives. We aren't going to throw those away because one scientist thinks they are too imprecise. The argument against computer models also ignores the diversity of models that are out there and the consistency of the conclusions those models point toward. Moore emphasizes disagreements over the role of water vapor. It is true, there is more disagreement over the role of water vapor in the global warming process than there is about global warming in general. A study published last year indicates that additional water vapor enters the stratosphere -- high above the CO2 -- as a result of global warming and significantly heightens the warming effect. Yet even if some details of this or that model prove to be incorrect, the predictions already made, even with the relatively rudimentary tools of 20 years ago, have held up remarkably well. This has also long been the case with weather models: Their track record is far from perfect, yet good enough that we don't want to live without them.
On TV, Moore has painted himself as a conspiracy theorist and termed the scientific consensus a "religious cult." The conspiracy is necessary to his argument because he lacks the extensive research needed to prove his scientific claims. In fact, claims like his have been considered and discarded over and over again in the hundred years that scientists have been studying this topic. When your outlet isn't a peer-reviewed scientific journal but "Hannity" on Fox News, conspiracy theories work better than facts.
Moore's youthful activism has put him in harm's way more than once as he worked to try to convince governments to change their policies on nuclear testing and whale hunting. I have a deep respect for that. But these days, he is bringing that same passion in defense of some backward-looking claims.
How CO2 Warms the Earth
In his testimony, Moore makes the claim, that "no actual proof, as it is understood in science, exists" for the role of carbon dioxide in global warming. But even without the computer models, there is proof. It may not satisfy him and other denialists, but it does exist and it satisfies the majority of climate scientists. The mechanism by which CO2 serves as a greenhouse gas is fairly simple. Energy from the sun hits the Earth's atmosphere at various wavelengths. Some of that energy bounces off into space, while some passes through the atmosphere and is either absorbed or reflected by the Earth's surface. As the Earth's surface warms, it radiates heat back to the atmosphere. Some of that radiated heat is lost to the upper atmosphere and to space, while some of it is absorbed by gas in the lower atmosphere and radiated again, back down to the planet. This effect is important for temperature stability and for life on the planet to exist. Planetary objects like the Moon, which has no atmosphere, or Mars, which has a very thin atmosphere, can fluctuate hundreds of degrees in temperature as the surface passes from light to shadow. Our atmosphere protects us from those extremes, modulating the heat and keeping us within a more livable range of temperatures. Carbon dioxide is the most important of the atmosphere's so-called greenhouse gases, absorbing more of the Earth's radiated heat and hanging around longer, taking as long as thousands of years to work its way out of the atmosphere. Its molecular structure makes carbon dioxide more effective as a greenhouse gas. The bonds between its atoms happen to vibrate in resonance with the infrared frequencies given off by the radiation of heat from the Earth's surface. That sympathetic vibration absorbs the energy and radiates it out again, some of it going back down to the surface, like an echo. As carbon dioxide levels build, the echo gets louder. The lower atmosphere becomes a heavier and heavier blanket and warming of the surface increases. Scientists can tell the increase of CO2 in the atmosphere is largely man-made by looking in part at the ratio between certain carbon isotopes, or variants of the molecule. That isotope profile points to a growing presence of CO2 from fossil fuels. Ignoring Science to Prove Science Comparing the Earth's temperatures and CO2 levels throughout history, using ice core samples, for example, shows the direct correlation between CO2 and surface temperature. Over the last 50 years, CO2 levels have increased dramatically and temperatures have similarly increased. Moore said that correlation is faulty because of "pauses" in global warming, most notably in the period from 2000 to 2010. In order to make that statement he has to ignore the recent science that has found ocean temperatures increasing as they absorb heat and transfer it to lower levels. The models predicted that scientists would find heat trapped in the oceans -- canceling out the data that indicated a pause in rising temperatures at the surface -- and they did. That gives the science more credibility, not less. His theory correlating changes in surface temperature with solar activity is as old as the topic itself; they have been considered and discounted.
Moore also said IPCC scientists aren't taking into account a period of global warming from earlier in the century (1910 to 1950). The answer is simple: Scientists focus on the current 50-year period because they have much more data from that period. However, no one claims the influence of human-based CO2 suddenly switched on in 1950, but rather that it had been growing steadily over the century and half prior.
Many scientists would agree with Moore that some of the global warming we're seeing is part of a natural cycle, but they would add that the recent rise (the last 50 years in particular) can't be described as a purely natural phenomenon.
These missing pieces of the argument seem to be a habit of denialists -- using one fact as a target while ignoring the contextual data that gives it meaning.
Moore himself seems to imply a manmade influence on global warming. Note the use of the qualified term "not the dominant cause" in the statement I quoted at the top of this article. That means CO2 is a contributing factor. He is saying most of global warming is natural, but he's leaving the door open to the contribution of human activity. But he doesn't want his audience to consider that. By painting his argument in such strident terms, he is attempting to discredit the work of his fellow scientists, without proof. He is encouraging layman and policy makers to reject the evidence of the man-made signature of CO2, the correlation of CO2 levels and industrialization, or the correlation of CO2 levels and global warming. He is encouraging them to disregard the science and bury their heads in the sand, simply because he said so. Turn Up the Heat Importantly, Moore doesn't dispute that the world is warming. Global warming, he said, is a good thing. Don't worry. Be happy. [H]umans are a tropical species. We evolved at the equator in a climate where freezing weather did not exist. The only reasons we can survive these cold climates are fire, clothing, and housing. It could be said that frost and ice are the enemies of life, except for those relatively few species that have evolved to adapt to freezing temperatures during this Pleistocene Ice Age. It is "extremely likely" that a warmer temperature than today's would be far better than a cooler one. Presumably, we will enjoy longer summers at whatever is left of the beach. An open shipping channel across the Arctic Sea. Bikinis as formal wear. A bigger market for sunscreen. The benefits boggle the mind. Nevermind that humans developed agriculture and urban centers only in the last 12,000 years, adapted for current climate conditions. Nevermind that millions of people live not in trees or caves but in permanent structures a stone's throw from sea levels that will soon swamp them. Nevermind that weather patterns will shift in unpredictable ways, making even some landlocked population centers uninhabitable or that crop yields already stressed to feed the world's burgeoning population will likely suffer huge losses. Nevermind that entire species will be wiped out by sudden environmental changes. Nevermind that many investors, including many reading this article, will go broke when markets exposed to any part of the global warming crisis collapse because of human inaction. If Moore is right that CO2 is irrelevant, then he needs to prove that case, build a new scientific consensus on a large body of evidence and offer some path toward mitigation of the worst effects, whatever the cause might be. The current consensus already has done that, proving its case to the satisfaction of the world's scientific community, with voluminous reports representing the work of thousands of researchers from all parts of the globe. More importantly, it offers a constructive way forward to prevent much hardship and suffering. -- Written by Carlton Wilkinson in New York
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