Speaking on BBC Radio 4's Today programme, Marburger said that although there was uncertainty in the climate models, increasing human carbon dioxide emissions would simply make the planet 'hotter and hotter' without an 'end point'.
However, Marburger poured doubt on the widely accepted temperature limit of 2 degrees above pre-industrial temperatures as the level at which global warming should be halted.
'I think that 2 degrees is rather abitrary,' he said. 'It's not clear to me that the answer shouldn't be three degrees, or more, or less. We don't have a scientific basis for selecting the two degree number - it's a hunch, a guess'
Asked whether he subscribed to another widely accepted number - that the world has just fifteen years to act on CO2 emissions - Marburger said that he couldn't think of a scientific basis for the figure:
'Let's forget about these artificial numbers and get on with the business of changing the energy technology, that's what we need to do,' he said.
His views stand in stark contrast to those of Vice President Dick Cheney, who wants to hold a debate on the possible causes of climate change.
This article first appeared in the Ecologist September 2007