Synchronized probes explore Bermuda Triangle’s swirling vortices

June 20, 2012 – OCEAN – Some might say that University of Washington oceanographers did well to only lose one of 21 underwater probes, given that they were deployed near the notorious Bermuda Triangle, where boats and airplanes have been known to disappear without a trace. The scientists chose the location to research its swirling whirlpools via a pioneering experiment that repeatedly sent the probes deep into the ocean and back to the surface in unison. “Nothing like this has ever been done,” said Tom Sanford, an oceanographer at the UW’s Applied Physics Laboratory. “It will be the paradigm for future experiments.” Typically, oceanographers may deploy an instrument in one place and then travel by boat to another spot to launch it again. What’s mysterious are these vortices that exist due to various processes and float around for a long life, banging into each other. They may be responsible for ocean mixing,” Sanford said. A vortex is a swirl of water that can be created in several ways, including water being pushed between land masses and then released into the open ocean. The subsurface features are hard to measure, Sanford said, because when they pass an underwater sensor they appear to be waves. Only by locating other sensors nearby at the same moment can researchers identify that movement as a swirl and not a wave. Scientists are interested in ocean mixing in part so they can learn more about how climate change might affect the deep ocean. Researchers know that the atmosphere, tides, sunlight, and surface and internal waves affect the temperature of the top few meters of the ocean. They also have some understanding of large-scale eddies and ocean dynamics, visible via satellite images, that cause broader ocean mixing. Now that the expedition is complete, the researchers have started analyzing the data. Their initial graphs simply plot the raw data, with a squiggly vertical red line depicting the upward trajectory of each profiler and a blue line their downward paths. But they hope to be able to draw conclusions by more closely studying the data. –Physics