Climate scientists are shaking their heads in disbelief over a press release from the UK's University of Leicester about a "new theory to explain global warming." According to a Russian researcher, rising global temperatures are the result not - as is now nearly universally accepted among climate experts - of increased carbon dioxide levels but of a meteor that crashed in Siberia at the turn of the century.

Yes, it's true. We're not making this up. The headline on the press release was "Greenhouse theory smashed by biggest stone." The scientist suggests that the meteor so affected water vapor concentrations in the atmosphere that it changed the world's climate.

There's only one problem, however. (Well, okay, there are several problems. But here's the obvious one.) According to the esteemed climate researchers at RealClimate, an event such as a meteor hitting would have relatively quick impacts on climate. But nothing in the record for the period when the meteor crashed shows anything out of the ordinary.

Further, water vapor does not hang around in the air like carbon dioxide. It stays in the air from a few days to a few years, depending on whether it's in the upper or lower atmosphere. So there is really no way we would still be feeling the impacts today.

As the folks at RealClimate say, the question is not whether the meteor is the culprit for climate change. It's "why the University of Leicester thought that this was worthy of a press release in the first place."