I had a friend who recently talked to me about his worry of Planet X
Here's more links:
A more rational link
Anyway, we started swapping conspiracy theories, and I related one of my favorites that I made up:
In Fingerprints of the Gods, Graham Hancock makes the case the when the polar caps grow too large, the extra weight of the eventually throws off all of the earth's crust & the whole crust shifts as a whole in a cataclysmic event. Then the ice, no longer at the poles, melts and the area area that now occupies the poles freezes. This is cyclical, and has already happened many times in the history of our planet (according to Hancock).
My pseudo-science counter-theory is this: a select few people on earth know about this huge impending cataclysm, and out of the kindness of their own hearts, have encouraged the accelerated use of fossil fuels & the wide scale manufacture of green house gasses to prevent the poles from building up too much ice. These people, oil tycoons, the Bush family, Saudi rulers, etc... appear on the surface to be greedy, colluding, shortsighted nimrods, but they hold their tongues and let their reputation be tarnished, lest the truth be found out and worldwide panic & rioting ensue.
This might sound far fetched, but it's the only reasonable explanation to account for their odd behavior.