President Barack Obama addresses the graduating class of the University of California, Irvine.

President Barack Obama addresses the graduating class of the University of California, Irvine. Photo: AP

Anaheim: United States President Barack Obama, appearing emboldened after his recent move to cut carbon emissions from coal-fired power plants, ridiculed members of the US Congress for denying climate change or pleading scientific ignorance as an alibi for avoiding an inconvenient truth.

Speaking in gleefully sarcastic terms to a commencement ceremony at the University of California, Irvine, on Saturday, Mr Obama likened those who deny climate change to people who would have told US president John Kennedy, at the dawn of the space program, that the moon ''was made of cheese''.

He saved his most scathing words for lawmakers who say they are not qualified to judge the issue because they are not scientists. These people,  Mr Obama said, recognise the truth but will not utter it for fear of being ''run out of town by a radical fringe that thinks climate science is a liberal plot''.

''I'm not a scientist either,'' Mr Obama told  the young audience, "but we've got some good ones at NASA. I do know the overwhelming majority of scientists who work on climate change, including some who once disputed the data, have put the debate to rest.''

 Mr Obama also said he had hit upon a novel way to speed up the nation's response to hurricanes, floods, droughts, tornadoes, wildfires, mudslides and other natural disasters: Make states and cities compete for a $US1 billion pot of money.

Mr Obama announced the competition, which would award funds to state and local authorities with the most innovative plans for rebuilding in a way that protects against future disasters.

''We also have to realise, as hundreds of scientists declared last month, that climate change is no longer a distant threat, but 'has moved firmly into the present','' Mr Obama said.

''Today's Congress,'' he declared, "is full of folks who stubbornly and automatically reject the scientific evidence. They will tell you climate change is a hoax or a fad. One member of Congress actually says the world might be cooling."

He added: "I want to tell you this to light a fire under you. As the generation getting short-changed by inaction on this issue, I want to tell you that you cannot accept that this is the way it has to be."

New York Times