On the Air: August 23, 2015
All of the Earth's oceans exchange water, so technically there is only one global ocean. Credit: National Oceanic and Atmospheric Administration

Many adventurers yearn to “sail the seven seas” -- to ply all the world’s oceans. Well, we have a little bad news for those folks. There aren’t seven oceans. In fact, there’s only one -- the global ocean.

Modern-day maps typically show five oceans: the Pacific, Atlantic, Indian, and Arctic, plus the recently designated Southern Ocean. All but the Southern Ocean are at least partially bounded by the continents or by strings of islands, which makes them look like separate bodies of water -- but they’re not.

In Print: August 1, 2015
A green sea turtle in Hawaii. Credit: Claire Fackler, National Oceanic and Atmospheric Administration

Shortly after sea turtles hatch and enter the waves, they vanish from sight for the next two to ten years. Scientists often call these the “lost years” because no one is sure where the turtle toddlers go during this time. Until recently, many marine scientists believed the young turtles ride the waves until they gain the strength or navigation skills to actively swim. But scientists wanted to find out for sure, especially since sea turtles are endangered. Knowing where they are going and how they are getting there might make it easier to protect them.