‘The most comprehensive modeling yet carried out on the likelihood of how much hotter the Earth's climate will get in this century shows that without rapid and massive action, the problem will be about twice as severe as previously estimated six years ago – and could be even worse than that.’

It is worth noting that this study advances the argument, also mentioned at the Copenhagen Climate Conference by Lord Stern, that the most cost effective approach toward climate risk mitigation is to act quickly as there are increasing mitigation costs and risks with delay. The article goes on to quote study co-author Ronald Prinn:

‘Because vehicles last for years, and buildings and power plants last for decades, it is essential to start making major changes through adoption of significant national and international policies as soon as possible, Prinn says. “The least-cost option to lower the risk is to start now and steadily transform the global energy system over the coming decades to low or zero greenhouse gas-emitting technologies.”‘

via Climate change odds much worse than thought – MIT News Office.