Human activities in the sea are often quite noisy. The effects of underwater sound on marine life can range from very subtle behavioral impacts to death. Only recently has the managmement of sound-related impacts been included in the legislation in Europe and overseas, forcing developers and planners to rethink their activities.
Thanks to one of our newest team members, Frank Thomsen, DHI now integrates extensive acoustic and biological expertise with its state-of-the-art modelling capabilities, enabling scientifically sound and reliable predictions and impact scenarios of noise in the marine environment.
Sound travels through water about four times faster than through air – depending on the temperature,
salinity and pressure of the water. This hypothetical map shows the potential range and levels of noise
produced by underwater pile driving - e.g. for the construction of an offshore wind farm - in the Inner
Danish Waters. Such sound maps are used together with data on the distribution and abundance of fish
and marine mammals to provide an estimate of the number of individuals affected. The impact is then
extrapolated using data on hearing sensitivities and demonstrated effects.
Frank Thomsen is a marine biologist with a long history of investigating the influence of underwater noise on marine mammals and fish. “My knowledge and experience will clearly strengthen the impact assessment of offshore constructions, hence increasing our clients chances to get their project approved and commence swiftly”, says Frank, “In addition, it will benefit the marine inhabitants.”
Frank Thomsen carried out his Ph.D. work on the whistles of killer whales.
Frank will carry out noise related impact studies and forecasts as well as detailed noise risk assessments for a variety of activities, ranging from the construction and design of offshore wind parks to impacts from shipping. These will allow us to advise the right measures to manage sound related impacts, ensuring that developments advance smoothly and with an acceptable environmental footprint.
Before joining DHI as a Senior Scientist, Frank worked as a Program Manager at the Centre for Environment, Fisheries and Aquaculture Science (Cefas) in the UK, advising regulatory bodies such as Defra (Department for Environment, Food and Rural Affairs) on offshore EIAs (Environmental Impact Assessments). He also has extensive experience advising international bodies such as OSPAR and the EU on noise impacts and managed a variety of scientific projects on underwater noise and other issues.