ABSTRACT
Forty-six nations and 2.6 billion people are now at risk of being overwhelmed by armed conflict and war related to climate change. A further 56 countries face political destabilization, affecting another 1.2 billion individuals (Smith and Vivekananda, 2007). Climate change is today's biggest threat to international security and will intensify North–South tensions (Campbell et al, 2007). Climate change from greenhouse gas (GHG) emissions is a global externality that is almost irreversible, as GHGs reside in the atmosphere for centuries. Humans would be much better off reducing GHG emissions substantially rather than suffering the consequences of failing to meet this challenge (Arrow, 2007; Stern, 2007). The world cannot continue to emit increasing amounts of GHGs without eventually provoking unacceptable climate changes; many climate professionals claim we already have exceeded prudent levels of emissions.
