Obama warns of climate security risks as tough talks begin

US President Barack Obama warned Tuesday that global warming poses imminent security and economic risks, as negotiators embarked on an 11-day race to seal a UN pact aimed at taming climate change. Obama and others employed lofty rhetoric Monday to inject energy into the start of the UN negotiations, which are due to deliver a global masterplan on December 11. "Before long we are going to have to devote more and more of our economic and military resources, not to growing opportunity for our peopl