During the last ice age, the Atlantic Ocean’s powerful current system remained active and continued to transport warm, salty water from the tropics to the North Atlantic despite extensive ice cover across much of the Northern Hemisphere, finds new research led by UCL scientists. The findings, published in Nature , show that despite the Earth being in an ice age, part of the ocean’s interior — known as North Atlantic Deep Water (NADW) — was only about 1.8°C colder than today, far from the near-