MISSING METHANE MYSTERY

The latest issue of Oil & Gas Journal, oops sorry, American Scientist, contains a really interesting article on the very important and unexplained but almost totally overlooked leveling off of atmospheric methane concentration. This could prove bad news for global warming's true believers:

Worry over the effects of fossil-fuel carbon dioxide in the air has become a familiar theme in public discourse about climate change. But news accounts (and movies by former Vice Presidents) that focus exclusively on CO2 in discussing global warming neglect an inconvenient truth: Other gaseous emissions add substantially to the atmosphere's ability to trap heat. In particular, methane (CH4) produces a climate forcing that is more than a third of that produced by carbon dioxide. The concentrations of methane and carbon dioxide in the atmosphere have both risen dramatically since the start of the industrial revolution, but unlike its more familiar greenhouse-gas cousin, atmospheric methane has recently stopped increasing in abundance.

This happy development wasn't entirely unanticipated, given that the rate of increase has been slowing for at least a quarter-century. Yet the United Nations Intergovernmental Panel on Climate Change has predicated many of its conclusions on scenarios in which methane concentrations would continue growing for decades to come. Thus the recent stabilization of methane levels is something that some scientists are trying very hard to explain.

Jeez, this silly debate just won't go away.