In a paper in Environmental Science and Technology Libia R. Diaz-Valbuena, Harold L. Leverenz, Christopher D. Cappa, George Tchobanoglous, William R. Horwath, and Jeannie L. Darby crawl down into the cesspool and measure greenhouse gases generated in septic systems. Turns out to be about a factor of two less than the models used by the IPCC, which, as any sane person can tell you were not checked against a rather odious reality, but rather estimated from biological oxygen demand. This study is obviously a front runner for the 2011 IgNobels.
More, although not much, seriously there are a large number of septic systems out there, and while GHG emissions are small compared with those from fossil fuel combustion, in the US, about 0.12 tonnes equivalent to CO2 per person per year, compared to 23 for the total carbon emissions per person in industrialized countries, they are not quite zilch. This illustrates another major failing of the IPCC dependence on models.
Cue the wailers.
Thursday, March 17, 2011