#sonar

#sonar

AI Spots Shipwrecks From the Ocean's Surface and the Air with 92% AccuracyFinding shipwrecks may sound like stuff of movies, but it's an important part of naval research by the Navy. They're interested in finding shipwrecks that may help shed light on human history, including trade, migration and war.Unlike the movies, finding shipwrecks usually don't involve a map with a bloody X marking the location of the bounty - but science has the next best thing: sonar and lidar imageries of the seafloor.Leila Character of The University of Texas at Austin and colleagues, in collaboration with the United States Navy's Underwater Archaeology Branch, has used a machine learning artificial intelligence to spot shipwrecks off the coast of mainland USA and Puerto Rico.Character wrote in The Conversation:The first step in creating the shipwreck model was to teach the computer what a shipwreck looks like. It was also important to teach the computer how to tell the difference between wrecks and the topography of the seafloor. To do this, I needed lots of examples of shipwrecks. I also needed to teach the model what the natural ocean floor looks like.Conveniently, the National Oceanic and Atmospheric Administration keeps a public database of shipwrecks. It also has a large public database of different types of imagery collected from around the world, including sonar and lidar imagery of the seafloor. The imagery I used extends to a little over 14 miles (23 kilometers) from the coast and to a depth of 279 feet (85 meters). This imagery contains huge areas with no shipwrecks, as well as the occasional shipwreck.Character's computer model has an accuracy of 92% and she now hopes to extend the model to spot shipwrecks from around the world.#shipwreck #sonar #lidar #seabed #oceanfloor #archaeology #underwaterarchaeology #USNavy #artificialintelligence #AI #machinelearningImage: Shipwrecks off the coast of Washington at the depth of 25m. Character L, et al. (2021) Remote Sens. 13(9) 1759.

This Undersea Volcano Near Christmas Island Looks Like the Eye of SauronResearchers from Australian Commonwealth Scientific and Industrial Research Organisation (CSIRO) have discovered a previously unknown undersea volcano that look like the 'Eye of Sauron' from the Lord of the Rings trilogy.The researchers, who were aboard the ocean research vessel RV Investigator, used multibeam sonar to map the sea bed 280 km (174 miles) southeast of Christmas Island.From Tim O'Hara and the research team's post at The Conversation:Previously unknown and unimagined, this volcano emerged from our screens as a giant oval-shaped depression called a caldera, 6.2km by 4.8km across. It is surrounded by a 300m-high rim (resembling Sauron’s eyelids), and has a 300 m high cone-shaped peak at its the centre (the “pupil”)....Our volcanic “eye” was not alone. Further mapping to the south revealed a smaller sea mountain covered in numerous volcanic cones, and further still to the south was a larger, flat-topped seamount. Following our Lord of the Rings theme, we have nicknamed themBarad-dûr (“Dark Fortress”) and Ered Lithui (“Ash Mountains”), respectively.Image: Phil Vandenbossche & Nelson Kuna/CSIRO#ocean #LordoftheRings #LOTR #EyeofSauron #ChristmasIsland #caldera #underwatervolcano #volcano #seabed #sonar