I'd have to disagree with that almost entirely. Firstly, I don't think ice ages happen like clockwork - they're to do with a whole host of factors, including variations in the Earth's orbit, which are non-linear and therefore erratic. The Wiki article says "Many glacial periods have occurred during the last few million years, initially at 40,000-year frequency but more recently at 100,000-year frequencies", so it seems rash to say we're 'overdue' one.
Furthermore, ice ages happen over the course of thousands to tens of thousands of years, whereas the recent warming has been observed over the course of just a few decades. It's not so much the size of the change that's worrying (yet), it's the incredible rapidity of the onset.
Finally, it's well known that global climate is linked to the composition of the atmosphere (which is how we reconstruct the Earth's ancient climate, after all), so isn't at least reasonable, verging on almost certain, to suppose that the enormous level of industiral development that's happened over the past century, not to mention the accompanying deforestation, is going to have a huge impact on climate?
Bookmarks