Go With the Flow

We are usually pretty short-sighted about the world that we live in. To many of us, this planet is the ground we stand upon at this very moment. It is the bricks on the sidewalk and the grass spanning the quad. It is the asphalt under our cars, winding from city to city and coast to coast. However, at those coasts the Earth stops being so rigidly defined and transitions into a more fluid, variable state of matter: water. Over seventy percent of the globe is covered with it, which is something we tend to forget in our concrete jungles. Water is everywhere, and even what we do not drink has an enormous impact on the flow of nature.

Beneath the surface of the great, blue expanses that dominate the globe, there is more to consider, ever churning in the weaving underwater currents that lace among the ocean deep. These currents are so numerous and so intricate that their complexity is similar to that of the threaded strings used to make that itchy sweater your grandma gave you when you were a kid; over and under and in different directions. For most of us, it doesn't occur to ask her how she made it, but scientists always have to ask questions.

The team of researchers in this article* (Sutyrin et al.) are looking to get a better grasp of how ocean currents operate. They decided that instead of looking at the big picture all at once, it would perhaps be more insightful to place a metaphorical magnifying glass onto a small, yet puzzling ocean current that had drawn their attention off the coast of Libya. They hoped that by doing this, they could learn about the basic mechanistic behaviors of this specific current and, if successful, apply their understanding of this miniscule example to the much larger diagram of the entire ocean.

To examine the mini-current up close and personal, the team studied the paths of buoys that were caught in the current over a period of five months. After tracking these buoys, running complicated simulations and collecting hordes of data, they eventually came up with a theory, which they explained primarily with a legion of nightmarish mathematical equations, on how to predict the path, duration, and intensity of the current.

According to their conclusion, the current was the result of the massive quantity of swirling water resulting from its contact with the steep continental shelf. Because the oceans are in perpetual flux, the flow of water becomes agitated when suddenly confronted by a steep shoreline. This creates a phenomenon the scientists labeled as a “large mesoscale anti-cyclone,” which Google says is nothing more than a cyclone of a certain size that turns opposite the normal direction (clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere). Using this information, they were finally able to define the mathematical properties at work.

Ultimately, the team was able to extract an applicable law regarding deep-flow feedback from their data. The slope of the incline of the continental shelf is proportional to the basic drift speed of the current, suggesting that as one increases at a constant rate, the other does also. In an ideal world, the results from this study would be able to accurately predict any and all current behavior throughout the whole ocean, but I suspect that countless more studies will be required before such modeling will be possible. The good thing about scientists is that while they ask so many questions, they also do whatever it takes to find answers, and I am confident that they will keep studying buoy numbers until they no all of the secrets of our blue planet.

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