Obama adviser John Holdren relishing Congress challenge
President Obama's chief science advisor says the US is unlikely to pass legislation strong enough to tackle climate change in the near future.
Professor John Holdren told BBC News efforts would focus on cleaner technology, nuclear power and energy efficiency, which will not be enough in the long term.
A greater Republican presence in Congress has made it more sceptical about climate change, but Professor Holden is relishing the prospect of hearings into the subject:
"Any objective look at what science has to say about climate change ought to... persuade reasonable people that the climate is changing and that humans are responsible for a substantial part of that."