From scientists to politicians, debate rages over whether the US should limit carbon dioxide emissions. The passing of laws to cap emissions by states such as California has emphasised that awareness without actionis not a viable course for the nation. The time has come to frame the issue in terms of finance, in order to find the most efficient way to mitigate the risks we face.   

Proof that carbon emissions cause warming should not be a pre-requisite to action. Whether you believe the science or not is beside the point. Policy should be more about risk than proof. How might financial markets assess this risk?