National Geographic: Military Sonar May Give Whales the Bends, Study Says: Undersea noise from naval exercises appears to give beaked whales the bends, an ailment most commonly associated with scuba divers who rise to the ocean surface too quickly ...... Scientists for years have suspected a link between sonar activities and mass strandings of marine mammals—similar events have occurred recently in the Bahamas and Greece—but they are uncertain as to why sonar causes the animals to strand themselves. ....... They found gas bubbles in blood vessels and hemorrhaged vital organs. ..... Sonar technology, such as that used during the Cold War, was passive: essentially big microphones that listened for the distinctive sounds emitted by large submarines. ....... Environmentalists say incidences of marine mammal strandings have sharply increased since this mid-frequency sonar technology was deployed. Environmentalists are now actively opposing testing of a new technology, called low-frequency sonar, which they say would significantly expand the geographic range the sound travels. ...... the sonar likely either causes a behavioral change in the whales such as rising too rapidly, or there is a physical effect of the sonar on bubble precursors in nitrogen-saturated tissues. ...... low-frequency sound waves can rapidly compress and then expand microscopic bubbles of gas in the tissue. Each sound wave causes the bubble to absorb more and more of the gas dissolved in the bloodstream, eventually making the bubbles big enough to rupture tissues.
Standout App
Sonar was an app that stood out of the many that presented at the TechCrunch Disrupt. I am not saying that was the best app. I am not saying I watched all presentations. I did not. But Sonar is the one I remember.
