Lake Como, in Northern Italy
Sometimes, the collective knowledge of generations of locals is just as valuable as a network of high-tech sensors. That’s what scientists studying the fluid dynamics of Lake Como in the Italian Alps found, when they began to interview fishermen.
The team from the University of Western Australia had been studying the complex currents and temperature gradations in the Y-shaped lake for some time, using a system of floating sensors. Alongside them were the approximately 30 local fisherman who go out each night to string out their giant gill nets, as much as 2,300 feet long and 27 feet high. In the morning, the fishermen retrieve the nets and any fish—mostly shad and whitefish—that have swum into them overnight. Read More
Along the top of this satellite image lies the coast of South Africa, but follow the sheets of clouds south about 500 miles, and a beautiful, incongruous-looking blue swirl appears. That plankton-laced eddy, which is 90 miles wide, is the oceanic version of a storm, spun off from a larger current and caused by roiling of water instead of air. Eddies in this region bring warm water from the Indian Ocean to the South Atlantic, and they can even pull nutrients up from the deep sea, fertilizing surface waters and causing blooms of plankton in areas that are otherwise rather devoid of life. It is just such a bloom that lends this eddy its cerulean hue.
Image courtesy of NASA’s Earth Observatory
What’s the News: Scientists have already bent light to make invisibility cloaks and manipulated sound to hide underwater objects from sonar. Now, researchers have come up with a preliminary design for a mesh shield that would let submarines stealthily maneuver through the seas without leaving any wake, they report in a study published online last week.
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