Cecil's latest column on global warming [April 7] is far from "Straight Dope." The connection between burning fossil fuels and global warming is the amount of carbon dioxide in the atmosphere. And atmospheric CO2 has been measured directly for decades. The measurements have gone up. Cecil raises the point that the burning of fossil fuels is a small fraction of the flow of CO2; true, but the question is whether it leads to an important increase.
Scientists discuss the matter in terms of billions of tons of carbon (since the carbon goes from CO2 to carbohydrates and back during photosynthesis and respiration). About 100 billion tons enter into photosynthesis every year. Fifty billion of those are returned to the atmosphere by plant and animal respiration; the other 50 billion enter into the soil and are returned to the atmosphere later by rotting. One hundred four billion enter the ocean, and 100 billion are returned to the atmosphere.
Back in 1989, when the article in Scientific American which is my source was written, fossil fuels contributed five billion to the atmosphere and deforestation contributed another two. That left a net increase of three billion tons of carbon in atmospheric CO2. This was slightly less than one half of 1 percent increase per year. If emissions had not increased since then, that rate would have resulted in a 7 percent increase by now. That's enough to raise temperatures significantly.
If Cecil is not convinced by the strong scientific consensus around the most thoroughly researched scientific question of the 21st century, he does state with absolute certainty that conforming to the Kyoto Protocol would mean shrinking the U.S. economy. The first time I read this claim, I asked the economics Internet newsgroup whether there had been any research supporting it. I got no response, and when I repeated the question to an economist I had befriended on that newsgroup in the past he had heard of none. Cecil cites nothing supporting this claim either. Presumably, his Ouija board told him so.
Cecil Adams replies:
I ventured no opinion on whether human activity has contributed to global warming. The point of my column was that arguments about how much it has or hasn't miss the point--there's no realistic way to reduce anthropogenic CO2 emissions in the short term. The U.S. Department of Energy's Energy Information Administration has projected that world carbon dioxide emissions will increase more than 50 percent between 2002 and 2025, from 24 billion to 39 billion metric tons (International Energy Outlook 2005, table 10). If the industrialized nations participating in the Kyoto Protocol ("Annex I" countries) achieve their goals, the EIA projects that by 2025 their CO2 emissions will be reduced by only 0.6 billion tons (IEO 2005, table 12). Meanwhile, emissions in developing countries, which under Kyoto are exempt from reduction requirements, will increase nearly ten billion tons. In short, we're going to see a huge jump in emissions no matter what industrialized nations do.
I never said anything about Kyoto "shrinking the U.S. economy." We didn't ratify the treaty; it won't affect us. Kyoto will certainly impose major costs on participating nations, many of which will be able to achieve their reduction goals only by purchasing emissions credits from countries whose economies have shrunk already, namely the former members of the Soviet bloc--meaning the participating nations won't necessarily be doing much reducing themselves. The EIA notes that "recent analysis has indicated that the cost of achieving domestic reductions in countries such as the United Kingdom may have been underestimated," and that while Japan may meet its goals, that will be partly because of a shrinking population in later years (in IEO 2005, pages 84 and 85).