The current concentrations of carbon dioxide in the atmosphere could prevent a build up of ice sheets over time, according to a new report.

Ashley Cooper/Corbis

arth isn't due for another ice age for 1,500 years. But by then, say researchers from Cambridge University, carbon dioxide emissions appear likely to have raised the planet's temperature so much that the ice sheets will be unable to form. Will climate change "block" the next ice age? Here, a brief guide:

Wait — an ice age?
Yup. The planet experiences regular ice ages — scientists have discovered evidence of five of them — and we're due for another one. "The period between the end of an ice age and the beginning of the next is typically about 11,000 years," says Britain's Telegraph, "due to a natural cycle related to the Earth's orbit." 

So when is this one supposed to hit? 
Around A.D. 3500, "the world will be due for another round of chilling and frozen wastelands," says the International Business Times. We're actually already overdue — it has been 11,600 years since the last ice age. But scientists determined that we're still 1,500 years out by comparing current conditions to a similar period between ice ages 780,000 years ago.

And this next one might not hit?
Probably not — at least not with current concentrations of carbon dioxide in the atmosphere. For the next ice age to hit, CO2 levels would have to fall to 250 parts per million by volume. Right now? The current carbon dioxide concentration is 390 ppmv — and at that level, the ice sheets just can't expand.

So that's a good thing, right?
Not exactly. Man-made climate change could have "huge consequences" for the planet, says study leader Dr. Luke Skinner. And the argument that CO2 emissions might be helping the planet is "missing the point."

Sources:  International Business Times, National Post, Telegraph