Post by DHI

Next up on 𝗠𝗼𝗱𝗲𝗹𝗹𝗶𝗻𝗴 𝗶𝗻 𝗽𝗿𝗮𝗰𝘁𝗶𝗰𝗲, we chat with Matthias Ram, Hydroacoustic Expert from DHI, about what underwater noise modelling involves, where it matters most in real‑life projects and how results guide permits, construction planning and mitigation at sea. 𝗤: 𝗟𝗲𝘁’𝘀 𝘀𝘁𝗮𝗿𝘁 𝘄𝗶𝘁𝗵 𝘁𝗵𝗲 𝗯𝗮𝘀𝗶𝗰𝘀. 𝗪𝗵𝗮𝘁 𝗶𝘀 𝘂𝗻𝗱𝗲𝗿𝘄𝗮𝘁𝗲𝗿 𝗻𝗼𝗶𝘀𝗲 𝗮𝗻𝗱 𝘄𝗵𝘆 𝗱𝗼 𝘄𝗲 𝗺𝗼𝗱𝗲𝗹 𝗶𝘁? Underwater noise is unwanted underwater sound that is typically generated as a byproduct of human activities — and it travels much farther than most people expect. In fact, sound from a single noise source can affect marine life tens or even hundreds of kilometres away. Even technically useful sounds, such as sonar pulses or sound from seismic sources, can be considered noise from an ecological perspective. We are dealing with a whole range of different anthropogenic, i.e., human-caused, noise sources: ship traffic, pile driving, drilling, dredging, munitions clearance, seismic surveys and much more. Sound propagates very well in water, meaning that emitted noise can be detected even at considerable distances. At the same time, many marine animals — such as fish, whales and seals — rely on sound for communication or orientation and are therefore highly sensitive to noise. Noise can have various effects on these animals, ranging from the masking of biologically relevant signals to behavioural reactions such as freezing or flight, to temporary or permanent injuries and in the most extreme cases, even death. We model underwater noise to assess the risks of these effects and thereby enable safe, sustainable and environmentally sound developments. 𝗤: 𝗪𝗵𝗲𝗻 𝘆𝗼𝘂 𝗯𝗲𝗴𝗶𝗻 𝗮 𝗻𝗼𝗶𝘀𝗲 𝗮𝘀𝘀𝗲𝘀𝘀𝗺𝗲𝗻𝘁, 𝘄𝗵𝗮𝘁 𝗮𝗿𝗲 𝘁𝗵𝗲 𝗲𝘀𝘀𝗲𝗻𝘁𝗶𝗮𝗹 𝗽𝗶𝗲𝗰𝗲𝘀 𝗼𝗳 𝗶𝗻𝗳𝗼𝗿𝗺𝗮𝘁𝗶𝗼𝗻 𝘆𝗼𝘂 𝗻𝗲𝗲𝗱 𝘁𝗼 𝗳𝗶𝗴𝘂𝗿𝗲 𝗼𝘂𝘁 𝗯𝗲𝗳𝗼𝗿𝗲 𝗮𝗻𝘆 𝗺𝗼𝗱𝗲𝗹𝗹𝗶𝗻𝗴 𝗰𝗮𝗻 𝗵𝗮𝗽𝗽𝗲𝗻? We usually start with four key questions: what, where, when and which? 𝙒𝙝𝙖𝙩 may sound like the key questions in a criminal investigation guide our assessment: What is the source of the sound? Is it pile driving or a moving ship – and what specific characteristics define the sound emitted? 𝙒𝙝𝙚𝙧𝙚 does it occur, i.e., how deep is the water, what is the bathymetry like and what are the characteristics of the water and the seabed? 𝙒𝙝𝙚𝙣 – more precisely, during which season – a sound is emitted often has far greater implications than a layperson might expect, since the season can strongly influence the stratification of the water and thus the refraction of sound within the water column. And finally: 𝙒𝙝𝙞𝙘𝙝 animals can be expected in the region and how sensitive are they to sound? (𝘤𝘰𝘯𝘵𝘪𝘯𝘶𝘦𝘥 𝘪𝘯 𝘭𝘪𝘯𝘬) 👉𝗖𝗮𝘁𝗰𝗵 𝘁𝗵𝗲 𝗳𝘂𝗹𝗹 𝗤&𝗔: https://lnkd.in/g2XuptWx 👇𝗦𝘄𝗶𝗽𝗲 𝗳𝗼𝗿 𝘁𝗵𝗲 𝗵𝗶𝗴𝗵𝗹𝗶𝗴𝗵𝘁𝘀 #Modellinginpractice #underwaternoise #modelling