From this web site: http://www.optimumpopulation.org/opt.earth.html
At a 1990 per capita emission rate of about four tonnes of carbon dioxide per person per year, the world's optimum population level would not be much higher than two billion, living at an average 1990 lifestyle, in order to stabilise carbon dioxide concentration in the atmosphere. This can be simply demonstrated by integrating advice from the IPCC with basic facts about carbon dioxide emissions: see The crucial CO2 limit, OPT Journal, October 2003.
So based on projection and unproven theories, we need to get from 7 billions to 2!
How are we supposed to do that. Is this called GENOCIDE on wide scale.