Have you ever, even for the briefest of moments, thought about the age of the water in which you're surfing? Were you even aware that water could be dated? I can tell you that I've never thought of either of those things. Never once occurred to me that water could have an age. There have been times when I'm sitting out the back during a very long lull when I've contemplated how water I've probably fished in the mountains might have made its way into a wave I've ridden, but that's the closest I've come to making the connection between ocean water and how old it might be.
I ask because oceanographers announced recently that they've figured out the mechanics behind a massive layer of water in the North Pacific that is as much as 2,000 years old. You can radiocarbon-date the age of ocean water, it turns out, also a thing I find fascinating. Normally, ocean water churns itself over fairly regularly, bringing deep water to the surface where it evaporates, joins the atmosphere, and eventually rejoins the ocean after condensing into precipitation again.
But certain sections of the North Pacific seafloor are shaped such that very deep waters get trapped in a cycle where they gradually flow northward and toward the surface before reversing flow southward, where it falls back to the seafloor, never reaching higher than about 1.5 miles from the surface. This so-called "Shadow Zone" of ancient water takes up an area larger in size than all of Europe.
This cycle has apparently gone on like this, churning around and around very slowly but never leaving the Shadow Zone to evaporate, for millennia. Incredible, isn't it? Researchers discovered the very old water some time ago, but didn't realize the shape of the sea floor is what trapped it down there until recently.
What does it all mean? No idea. Scientists are very curious about the molecules locked inside the ancient water (Terrific band name, which I just copyrighted) to see what they can tell us about how f–ked the oceans are today, in terms of chemical composition, and just because they aren't really sure what could be in all that water anyway.
Unfortunately, there's a huge amount of carbon microscopic nutrients sort of sequestered in all that old water, too, carbon that hasn't been calculated yet when climate scientists estimate how badly we've filled our atmosphere with carbon dioxide, so that's bad.
Ancient seas within the seas. The ocean gets weirder and weirder the more you learn about it.