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: Most poisonous snakes don’t inject their prey with venom; instead, they bite the prey and venom insidiously trickles down a groove on their fangs into the wound. A new study in Physical Review Letters investigated the physics behind how venom travels down the grooves: It turns out that snake venom has unusual viscosity properties that keep it cohering together until it’s time to flow down the fangs and into the snake’s soon-to-be-snack—the same properties that account for how ketchup seems stuck in the bottle, then flows freely onto your fries.