The United States is not alone in these efforts. Because large shipping companies face pressure to comply with stricter carbon emission standards, propeller changes in tomorrow’s ships could help both shipping operators and the environment. One question is whether a quieter propeller that produces less noise would also be more efficient to make up the difference in upfront cost. In addition to noise, those bubbles are thought to create fuel inefficiency. For example, propellers can create bubbles underwater that burst with a signature sound. We’re finding win-win solutions to some of our problems. NOAA will continue to work with partners, including those within the shipping industry, to incentivize building new and retrofitting existing ships to be quieter. Coast Guard at the helm) led a group within the International Maritime Organization in ratifying voluntary guidelines on ways that ships can reduce noise. Other measures seek to reduce noise exposure for sensitive ecosystems within areas of designated national significance, like National Marine Sanctuaries.īecause shipping traffic is such a major contributor to chronic noise, in 2014 the United States (with NOAA and the U.S. For example, some measures can avoid noisy activities in specific places when they are important to protected animals or are important to fishery species. If those sounds could negatively affect marine animals or their habitat, NOAA can require measures and can recommend best practices to reduce negative effects. And sometimes how people use the marine environment can affect daily life and functions of marine species.įor this reason, NOAA works with other federal agencies and industries, who are proposing projects that might affect marine species and their habitat-such as oil and gas exploration and drilling, construction, or military training activities-that create loud underwater sounds over specified periods of time. But with the advent of the industrial age, people have drastically altered the underwater soundscape over the course of roughly a century. ![]() ![]() These animals have had 40 to 50 million years or more to evolve in their acoustic environment. It's possible that Whistle, unlike Julie, Slow Down or other mysterious sea noises, may have been caused by fire, not ice - though we won't blame you if you want to imagine it was Cthulhu after all.įollow Stephanie Pappas on Twitter or LiveScience. However, according to NOAA, similar sounds have been recorded coming from erupting submarine volcanoes. Recorded in July 1997, Whistle was only picked up by a single hydrophone, making it impossible to pinpoint its source. Whistle sounds more like a kettle of boiling water than a jaunty tune, but that doesn't make the sound any less mysterious. The suspected culprit? An iceberg dragging its keel along the ocean floor. Recorded in 1997, Train is a steady hum that likely originated in Antarctica's Ross Sea. Train sounds like you might expect a noise named train to sound - like the rub of train wheels against tracks. The sound was detected by sensors nearly 3,100 miles (5,000 km) apart. NOAA scientists have located the source of the sound off the Antarctic Peninsula, leading them to suspect that Slow Down is the result of a drifting iceberg hitting the seafloor and screeching to a ponderous stop. Slow Down, a noise recorded on May 19, 1997, gets its name because it descends in frequency over seven minutes. The source of the sound appears to be an area of undersea volcanic activity, but scientists have yet to pin down exactly what's causing it. ![]() It's been picked up by hydrophones seasonally since 1991, peaking in the spring and fall. ![]() To the ears, Upsweep sounds like an ambulance wail or perhaps an unearthly creature's howl. This sound is like the scratch of branches against your bedroom window, in that it happens again … and again … and again. In this case, NOAA researchers suspect the hydrophones picked up the sound of a large Antarctic iceberg running into the seafloor. Like the Bloop, Julia is most likely the sound of ice. The eastern equatorial Pacific autonomous array (a network of hydrophones) picked up this strange sound. This weird noise, which sounds almost like someone cooing or whining, occurred on March 1, 1999. This sound, dubbed "Julia" is a mystery, though it may be the sound of an iceberg running into the ocean floor.
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