Book to Note

Tyler Volk. CO₂ Rising: The World's Greatest Environmental Challenge. Cambridge, MA: MIT Press, 2008. xvi + 223 pp. $22.95.

Reviewed by Zoe Marquardt

Tyler Volk juxtaposes two apparently competing views of carbon dioxide (CO₂): that it is a naturally occurring molecule essential to maintaining life on earth and that the unprecedented growth in its levels over the last decades signals an unsustainable change in the carbon cycle. He familiarizes readers with the chemistry of the carbon cycle and the history of carbon detection by following “Dave,” a carbon atom who sometimes exists as one of the 42 x 1039 CO2 molecules in the earth’s atmosphere today. Named for C. David Keeling, a pioneering carboncycle scientist and obviously one of the author’s heroes, Dave appears variously in a glass of beer and in a gust of wind that turns the blades of a turbine. Yet CO2 Rising is not a oneman show. About halfway through his book Volk introduces readers to Oiliver, Coaleen, and Methaniel, who, unlike Dave, were purposefully extracted from the earth and have been in the biosphere for a much shorter period. Volk is quick to point out,that the origins of the three new carbon atoms (which are patently clear in their names) do not separate them from Dave—since being released into the atmosphere they have circulated in the same fashion as their “purer,” limestone-derived counterpart. Instead, the rising “birth rate” of carbon atoms accounts for the spike in global emperatures and the other symptoms of global warming that have become increasingly apparent in the last few decades. While some of his detours seem superfluous, Dave and friends are nevertheless more than competent tour guides to the complexities of the carbon cycle.