As much as pollution has contaminated our oceans, it would be surprising to find that there are still parts of the deep blue that sit untouched.
Some 700 years ago, before mankind began pumping carbon into the atmosphere and warming the climate, the Earth chilled in a centuries-long cooling event called the Little Ice Age.
Today, new research finds, the depths of the Pacific still hold memories of this colder time. Just over a mile (2 kilometers) down, the Pacific Ocean is getting a tad cooler as waters that were last at the surface during the Little Ice Age are only just now mixing with deeper, warmer waters.
(Image credit: Anastasia Taioglou/Unsplash)