US SENATOR James Inhofe wants to have his carbon and eat it too.

Inhofe, a prominent climate-change denier, co-aut d legislation last week to study the impact of black carbon, or soot, on climate change and ways to reduce the emissions of the pollutant.

Nevertheless, he maintains that the bill in no way suggests he has reversed his stance on climate change. In fact, on the day the legislation was submitted

In it he attacked the false notion that man-made greenhouse gases threaten our very existence. Inhofe's representatives say he backed the bill to tackle the health concerns relating to black carbon, which is emitted as soot from burning biomass, diesel and other fossil fuels.

But its impact on climate change is significant too. A study in 2008 found that soot is second only to CO2 as an agent of global warming. But soot washes out of the atmosphere in a matter of weeks after it is emitted, so reducing emissions could have an immediate effect on climate.