The Inter-governmental Panel on Climate Change had calculated that a relatively safe level of carbon dioxide emissions globally would be 14.5 gigatonnes per year. Roughly calculated, this comes out to be 2.25 tonnes per person per year, globally. However, data clearly shows that advanced nations are at per capita output levels that, if replicated by developing nations, would be dramatically in excess of safe levels.

World carbon emissions are now at about twice the safe-level. This means that if the current output is sustained, the carbon dioxide stock in the atmosphere will rise above safe levels in the next 40 years. Safe levels of emission could be achieved by reducing advanced nations’ emissions by a factor of two or a little more.

Technology to reduce per capita emissions are either too expensive or so costly as to be certain of slowing global and developing countries’ growth. Though population growth is viewed as the problem, the most projected growth in emissions is not in high-population growth countries. The real challenge is accommodating high-speed economic growth in what are currently large populations.