The US president's chief science adviser says the nation's current efforts to tackle climate change are insufficient in the long-term.
Speaking to BBC News at the American Association for the Advancement of Science (AAAS) meeting in Washington DC, Professor John Holdren said the current US Congress was unlikely to pass new legislation to put a price on CO2 emissions.
President Obama's administration's efforts, he said, would instead have to focus on developing cleaner technologies, expanding the use of nuclear power and improving energy efficiency.
But he admits that in the long term, these initiatives on their own will not be enough.
"Ultimately, we will have to look to a future Congress for the more comprehensive approach that climate change will require," he said.
For the time being, Professor Holdren faces a more sceptical Congress than he would like, and one that proposes a series of congressional hearings to assess the science of climate change.
Professor Holdren says he is relishing the opportunity.
"Any objective look at what science has to say about climate change ought to be sufficient to persuade reasonable people that the climate is changing and that humans are responsible for a substantial part of that - and that these changes are doing harm and will continue to do more harm unless we start to reduce our emissions.
"If Congress wants to have a series of hearings to illuminate these issues, they are going to get illuminated."
Professor Holdren accepts that confidence in climate science has been dented by recent scandals.
But he believes public reaction was temporary and short-lived.
"I'm not so sure there's a lot of new scepticism in the climate change debate," he said.
"People are seeing the impact of climate change around them in extraordinary patterns of floods and droughts, wildfires, heatwaves and powerful storms.
"I think it is going to be very hard to persuade people that climate change is somehow a fraud."