Tree loses race with PC's CO2
Rick Nelson, Chief Editor -- Test & Measurement World, 2/1/2007
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What to do about climate change remains contentious. Possibilities extend from worldwide implementation of the Kyoto Protocol (Bush and Exxon still oppose that) to individual carbon-reduction efforts. To support individual efforts, Dell is soliciting customer donations to help plant trees. A $6.31 tree, Dell says, will in 70 years absorb the CO2 released by three years of PC operation.
The problem with this plan is the PC's tremendous carbon-generation head start. Back-of-the-envelope calculations show that the PC will contribute 1.7 picodegrees Fahrenheit of global warming by the end of its three-year life; temperature rise will continue for 66 years, to 28 picodegrees, when the tree begins catching up.
Dell's program can make customers feel virtuous through a meager $6 donation tacked onto a PC purchase. But to truly offset a PC's carbon footprint, customers would need to donate about $140 to plant 22 trees for each PC purchased.
Then they would need to make sure their trees get planted in the tropics. Writing in the New York Times, Ken Caldeira, a scientist at the Carnegie Institution's department of global ecology, notes that trees in temperate climes absorb more sunlight than the farmland they replace, which offsets the cooling influence of their carbon sequestration. Trees planted in the tropics, however, help form clouds, which reflect energy back into space. (In response to one of my blog posts on this subject, Caldeira commented, “Dell is helping to preserve forests in the lower Mississippi valley, which would probably have some slight global cooling effect.”)
All this is to say that climate change is too complex to be addressed at the individual level, even with a company like Dell handling the administrative work. Don't get me wrong—planting trees is good, and I hope Dell can generate significant donations to support reforestation. But keep in mind that Dell's effort is more of a marketing initiative than a serious effort to combat climate change.
What's truly required is what Times columnist Tom Friedman calls the “Green New Deal”—government programs and industrial projects to foster conservation and to perfect solar, wind, hydroelectric, nuclear, ethanol, biodiesel, and clean-coal technologies.
