The truth behind “the colliding seas”

The truth behind "the colliding seas". Surely you have seen a video where you see two masses of water of different colors that "collide" but do not mix. Most of these videos are about the Gulf of Alaska. And this belief is supported by the existence of images in which it seems that they really "collide". But what is true about it?

According to an Alaskan media outlet, this area is popularly known as "the place where two oceans meet", and the explanation is simple. The first thing they clarify is that there are neither two seas nor two oceans there, since all that area corresponds to the Pacific Ocean.

And there are several photographs of this phenomenon taken by photographer Kent Smith and researcher Ken Bruland. The latter is a professor of ocean sciences at the University of California-Santa Cruz. Bruland was studying how it is possible that in that area there were eddies that reached hundreds of kilometers in diameter. These eddies usually carry large amounts of glacial sediment with them thanks to the rivers that originate from the glaciers in the area. These water currents carry heavy sediment and clay that darken and cloud the water. All these sediments is what is known as “glacial flour”.

Once these rivers flow into a larger body of water they get caught up in ocean currents, moving from east to west, and begin to circulate. And this is the great mystery behind those photos and videos. They show how sedimentary river and ocean water meet.

What this researcher explains is that it is totally false that they never get together, if they do. What happens is that the differences in density, due to temperature, salinity and other factors, slow the process down. That is why the feeling that they do not come together, they do, but not immediately.

A similar effect (although more devastating) could be observed years ago due to the floods we had in Cartagena. And it is that the boulevards that flow into the Mar Menor were loaded with fresh water full of dragged sediments in which, from a satellite view, the difference between the waters of the floods and that of the Mar Menor could be observed. And with this we have revealed the truth behind “the colliding seas”.

Cover image property of Ken Bruland