Change in Temperature per ton of CO2?

In Science Daily, June 11th, 2009, Damon Matthews, a professor in Concordia University's Department of Geography, Planning and the Environment found a direct relationship between carbon dioxide emissions and global warming. Matthews, together with colleagues from Victoria and the U.K., used a combination of global climate models and historical climate data to show that there is a simple linear relationship between total cumulative emissions and global temperature change.