NASA recently announced that substantial changes are occurring on the surface of the Sun which could bring about the next long lasting cold era.
“When the surface movement slows down, sunspot counts drop significantly. And when we have sunspot counts lower than 50 it means only one thing – an intense cold climate, globally,” Casey said.
On a related note, there is an Interesting article here on global warming with loads of graphs. The Earth spends nearly all of its time colder than we are now. The Earth is normally several degrees colder, and every 100,000 years or so, it spikes up to a bit warmer than we are now for a few thousand years, then goes cold again. And in fact, science calls the current period an “interglacial”, a temporary gap in the long ice age.