The North Sea is one of Europe’s busiest seas and also one of the most acoustically complex. Every day, thousands of ships pass through its waters, offshore wind farms operate continuously, and seismic surveys add powerful sound signals. Together, these activities create an underwater sound environment that can affect marine life. As part of the DEMASK project, JASCO Applied Sciences helps to better understand this environment by analysing major sources of underwater noise and translating them into clear and comparable insights. This work provides an important first step before more detailed and computationally intensive modelling begins.
From complex soundscapes to clear insights
In DEMASK, JASCO focuses on modelling underwater noise rather than measuring it directly. The work centres on calculating sound energy from major sources, including commercial shipping, operational offshore wind farms and seismic surveys. “Before moving into detailed modelling, it is important to understand where the main contributions come from,” explains Özkan Sertlek, senior scientist at JASCO. “Our work focuses on sound energy calculations. This practical approach helps identify the most important sound sources, compare them, and understand their contributions to the soundscape before moving on to more detailed simulations.”
Practical metrics that save time and effort
Jasco works closely with other partners in the DEMASK consortium, particularly TNO. While JASCO provides simplified and practical sound energy calculations, TNO builds on these results with more detailed modelling and sound mapping. Regular technical exchanges ensure that methods are aligned and that results can be used efficiently in later project stages. One key outcome of JASCO’s work is the use of sound energy density metrics. These metrics make it possible to compare very different sound sources using a single measure. “These metrics are not meant to replace detailed modelling,” Sertlek says, “but they provide a fast and informative overview. This helps save time and focus effort where it matters most.”
Looking ahead to offshore wind noise
As DEMASK progresses, JASCO’s focus is shifting from ship noise to operational noise from offshore wind farms. Shipping has long been a constant source of sound in the North Sea, but the rapid expansion of offshore wind adds a new and increasingly important component. “Ships are always present,” Sertlek explains, “but offshore wind farms introduce additional sound that can affect large areas. One of the key questions we are addressing is how this sound compares to ship noise.”
Supporting decision making and mitigation
The insights generated by JASCO are intended to support practical decision making. By identifying the dominant sources of underwater noise, DEMASK provides a solid basis for exploring mitigation measures and possible regulatory options. “If we understand which sources contribute most to underwater noise, we can start thinking about targeted mitigation,” says Sertlek. “This could involve shipping, offshore wind, or other activities.”
A shared effort across disciplines
For Sertlek, one of the most valuable aspects of DEMASK is the collaboration within the consortium. “Working with partners from different backgrounds leads to a lot of knowledge exchange,” he says. “It is motivating to see how different perspectives come together to address the same challenge.”
Even with a focused and practical role, JASCO’s contribution supports a broader understanding of underwater noise in the North Sea. By turning complex sound environments into clear and comparable information, the project helps improve assessments and supports better protection of marine life.