Al Gore's Claim About the Snow on Mount Kilimanjaro

(Fox News) - Al Gore has made the disappearing snows of Mount Kilimanjaro a cornerstone of his crusade against global warming.

In his film "An Inconvenient Truth" for example, he says: "Within the decade, there will be no more snows of Kilimanjaro."

But now researchers from the U.S. and Austria say global warming isn't the cause, and the fluctuations are nothing new.

American Science magazine reports most of the current snow retreat occurred before 1953 — nearly two decades before any conclusive evidence of atmospheric warming was available.

One of the scientists writes: "It is certainly possible that the icecap has come and gone many times over hundreds of thousands of years."

The article says the disappearance of Kilimanjaro's ice is not driven by warming air temperature, but by solar radiation — and that much of the ice is not melting, but vanishing by sublimation where ice at very low temperatures converts straight to water vapor.