On March 23 2009, Dr. Nina Fedoroff, the US State Department chief scientist and adviser of Hillary Clinton, stated: " famines that strike a billion people are quite possible in a world where climate change has damaged food production and the human population has risen to nine billion."

http://www.care2.com/c2c/groups/disc.html?gpp=3626&pst=1013288

Dr. Fedoroff echoes comments by John Beddington, Britain's chief scientist, who forecasts a "perfect storm" of food, water and energy shortages by 2030, when she told BBC One, that humans had exceeded the Earth's "limits of sustainability".

"We need to continue to decrease the growth rate of the global population; the planet can't support many more people," Dr Fedoroff added, stressing the need for humans to become much better at managing "wild lands", and in particular water supplies. "

http://news.bbc.co.uk/2/hi/science/nature/7974995.stm

Dr. Fedorrof is right; we need to be responsible on this issue. And rather quickly.