We are currently in an ice age, which is defined as any period during which there are ice caps.

The current ice age began 2.5 Mya. It is suspected that the cause was the gradual reduction in CO2 caused by the weathering of the Himalayas, the migration of Antarctica over the South Pole, and the closing of the isthmus of Panama blocking ocean heat transfer at the equator.

There have been over a dozen significant glaciations since the ice age began. They are likely driven by the orbital cycles of the Earth. In the last million years they’ve fallen into a regular pattern of ~90,000 years of advancing cold and ice, and ~10,000 years of retreating ice and relative warmth. We are in one of those warm periods now. It started ~12,000 years ago.

Winter is coming.