I gather from citing Dr Paupach that global CO2 emissions in 2005 were about 8 billion tons. This would put global per capita emissions a bit above one ton per person. I've read elsewhere an estimate that reducing emissions to 50% below 1990 levels by 2050 could limit global warming to an additional rise of two degrees Celsius, hopefully forestalling catastrophic effects. (I'm guessing a 1990 level closer to 6 billion tons or one ton per capita. So, 50% below that would be in the vicinity of 3 billion tons per year. Yes?) Since the global population is projected to be 9 billion by 2050, this 2 degree target seems to indicate a "safe" global per capita level of emissions by 2050 as 0.3 tons per year.
Comments to this blog and to ffrancispc@aol.com from anyone more familiar with these figures would be greatly appreciated.