Ice age

We are approaching the end of a 12,000 year period of stable and ideal climate. Global warming is a fact; man can speed it up or slow it down, but not stop it. The planet will warm and the oceans rise as the ice caps melt. The tropics will become uninhabitable and humanity will retreat toward the poles. This condition will last for many thousands of years and then a new ice age will begin–there have been several in the past. If humanity still exists on earth, humans will migrate toward the equator. The ice sheets may or may not meet at the equator but the deserts at their forward edges will meet and merge. The earth will be a frigid ball of ice again until the cycle starts over.