A googled trail of bread crumbs this morning lead me to the oddly named Friends of Science web page this morning, which includes this truly remarkable assertion:

The CO2 increase was only 0.4 percent over the last 50 years, rather than the 5 percent per 100 years quoted by Kyoto.

Let’s just briefly take a virtual jaunt to Mauna Loa, where Charles Keeling and his crew have been measuring carbon dioxide since 1958, which would seem to cover most of “the last 50 years” mentioned by our Friends of Science:

The Mauna Loa record shows a 18.8 percent increase in the mean annual concentration, from 315.98 parts per million by volume (ppmv) of dry air in 1959 to 375.64 ppmv in 2003.

Perhaps they meant 0.4 percent per year?