WOODS HOLE – The water of the deep Pacific Ocean last saw sunlight between the 9th and 12th centuries when the earth’s climate was generally warmer before the cold of the Little Ice Age.
Now ocean surface temperatures are back on the rise but scientists are trying to figure out if the deep waters know that.
Researchers from the Woods Hole Oceanographic Institution and Harvard University have found that the deep Pacific Ocean is a few centuries behind in terms of temperature and is still adjusting to the entry of the Little Ice Age around the 16th century.
As most of the ocean is responding to modern warming the deep Pacific may be cooling.
Researchers developed a model to show how interior properties of the ocean respond to changes in surface climate.
They compared historic data of temperatures logged in the late 1800s with modern observations and found warming in most parts of the earths oceans, but cooling two kilometers deep in the Pacific.
The findings imply that variations in surface climate that predate the beginning of modern warming still influence how much the climate is heating up today.