By using an unlikely combination of radiometric dating techniques, scientists may have finally unlocked the mysteries that start, and stop, Earth's ice ages. Bonus: the Atlantic overturning circulation - the great ocean current that carries heat north, then sinks and flows back along the bottom of the ocean - that most recent of go-to bugaboos climate chicken-littles enjoy waving in everyone's faces, plays a primary role in ending an ice age, not causing it.