I saw something a few years ago where a geologist was doing tests on layers of sediment, and he said you could tell by certain things how the climate will change and he could see where the ice age happened and it had reversed the poles, etc. Then he said the pattern in the rocks shows that we're due to have another polarity reversal soon....like in the next 10,000 years I think he said. Of course, that shift in polarity doesn't happen quickly...it could take decades, but it's possible that that's what is happening. I have no idea. It was on National Geographic or Discovery.