Looking after the North Sea

The North Sea under pressure from competing uses

“For example, wind farms come with cables, energy hubs on fixed or floating islands, or conversion to green hydrogen at sea. That requires space, but also a picture of where all these things should be located. International agreements and coordination are needed here,” says Sharon Tatman, marine ecologist.

She has been working on projects throughout the North Sea for 25 years, studying the impact of interventions large and small. She took part in the ‘airport in the sea study’ in the late 1990s and saw how major developments in the North Sea required the development and, above all, the sharing of knowledge.

Tatman: “My focus is on how to supply data and knowledge in such a way that they are transparent and support policymakers with their story. Because whatever happens, space in the North Sea is short and, as on land, choices have to be made. Those choices are often made autonomously, but coordination remains vital. The North Sea borders on several European countries and it has many users, but it is a single natural system."

"Three years ago, we launched a knowledge exchange platform based on data for the Dutch section of the North Sea. Now we are expanding this platform for all the countries around the North Sea. They use the sea for activities like offshore wind, shipping, fisheries, nature and critical infrastructure. Cybersecurity and defence are also becoming increasingly important.”

"All these domains affect each other and use the natural system. Space is needed and, above all, an equilibrium. It is important for countries to be willing to share data. Things also get difficult when you don’t know where each other need space and how to get others involved. But that is the only way to look out for a healthy sea.”

North Sea Knowledge and shared data platforms

Deltares is currently contributing its North Sea knowledge to the Greater North Sea Basin Initiative (GNSBI), in which the responsible ministries and agencies of different North Sea countries are working to agree about coordinated plans in the North Sea.

They are emphatically also looking at all sectors that use this sea. For example, we are visualising the available data. Tatman: “We have the knowledge needed to establish data platforms with different web viewers.

From data specialists to policymakers

Those web viewers provide targeted access for users ranging from data specialists to policymakers. For next year, we are working on an encyclopaedic section for an even wider audience. The interactivity of this system is also relevant: initial assessments of interventions are needed.

Since housing all the information with a single organisation is ultimately a vulnerable approach, we are discussing a user case for continuity at EDITO. The data files about the North Sea are huge and the fact that the data are stored on European cloud environments is also not unimportant given the current geopolitical situation.”

Tatman concludes: “We often forget that the Dutch section of the North Sea is the largest nature area we have. The Dutch North Sea is 1.5 times the size of our entire country. I hope that, with a better understanding about the consequences of our use, we can also look after this area better. Because the latest OSPAR study has shown that nature here is not doing well.”

The ecological importance of a healthy North Sea

“There is another important reason to look after the health of the North Sea,” says Luca van Duren, a marine ecologist with fifteen years of experience on the North Sea. “Fifty percent of the Earth’s oxygen comes from the sea. The North Sea is not big but it is very productive. In addition, the North Sea supplies us with healthy food, and good, natural products. So some appreciation is certainly merited.”

Working with Wageningen Marine, Van Duren safeguards the scientific quality of the North Sea Nature Restoration Programme of the Dutch Ministry of Agriculture, Fisheries, Food Security and Nature (LVVN).

Nature protection, legislation, and restoration targets

“Nature is feeling the pinch. We have to assume our personal responsibility here but there is also European legislation that we, as the Netherlands, have agreed on. Until a few years ago, 99.6% of the Dutch continental shelf was ploughed up at least once a year by beam trawlers. That also happened in areas designated as nature reserves under Natura 2000 directives.

Each country could decide how to implement those directives itself. The Netherlands opted not to allow new activities in these areas (such as wind farms) but allowed all ‘existing uses’, such as fishing, to continue. In some other countries, the construction of wind farms was permitted in these areas but fishing was restricted. Under the new Nature Restoration Act, at least 30 per cent of the seabed must be protected by 2030, with one third being strictly protected.

That 10% of the Dutch Continental Shelf has to be a genuine nature reserve, and so wind farms or seaweed farms are not allowed. The other 20% must also be protected from beam trawling, sand mining and other activities that damage the seabed.

However, a less rigid approach will be possible. So this legislation opens up opportunities for nature, and particularly for species such as the flat oyster that have an important function in the ecosystem but that have been lost as a result of fishing.

“Wind farms can also play a role here, partly because beam trawling is not permitted. In addition, some gains may be possible by building those wind farms in ‘nature-inclusive’ ways. For example, you could try to encourage the settlement of oysters in wind farms, or design the undersea rock structures so that crabs, lobsters and fish find refuge there.

However, nature-inclusive construction is not a substitute for establishing nature reserves. Nature restoration mainly means just giving nature a chance to do its own thing. Nature is very resilient. In many cases, if you exclude human activities, recovery will follow naturally.

Understanding food webs and ecosystem impacts

“If you ask me what knowledge we should really be developing further now for the purposes of conservation, that is knowledge about the food web and the effects on protected species. Plankton is the base of the food web. Ultimately, all species depend on it. How do effects on plankton affect protected species? We know that all activities in the North Sea impact plankton.

Research programmes have provided us with more and more information in that respect. But the impact this has on cod, seals or gannets, for example, is very difficult to determine. In terms of new knowledge, I expect a lot from monitoring technology such as underwater drones, and from information technology. Interdisciplinary collaboration is not only instructive but also necessary given the complex questions facing us.”

Data-driven decision-making and spatial planning

Arjen Luijendijk is a Coastal Developments expert at Deltares. “Sand is important to protect the coast and it comes from the ‘shallow’ part of the Dutch North Sea. In the potential extraction area, other activities also require space. Wind farms, for example. What are the implications in the long run for sand mining?

I work a lot with data and models, and there is value for practical application if you provide policymakers and decision-makers with relevant information. The Virtual Climate Lab (VCL) is ideal for this purpose.

Virtual Climate Lab and shared understanding

On a 3D model, various layers of information are presented as colours, making questions, obstacles and choices visible. Those layers show, for example, the soil profile, waves, currents, ecology, safety and spatial planning: basically everything that is important in that particular physical environment. That means you need the data.

We present the in-depth information on a screen. The informal setting of a table of this kind has turned out to work very well. In conversation with one another, people soon share more practical knowledge and experiences. We have now set the lab up for the North Sea and it has already been tested with the GNSBI.

However, organisations and countries must be willing to share their data, and a good moderator is important: someone who knows the ins and outs, can see in advance where the complex questions are, and provide guidance with a range of scenarios.

As said elsewhere, if EDITO is interested, we will transfer the North Sea component to them so that it is available to all European North Sea countries.”

From virtual labs to a digital twin of the North Sea

Lorinc Meszaros, coastal and marine digital information expert at Deltares, and EDITO project leader: "The North Sea Knowledge Management Platform as an initiative of GNSBI, and better known as the Compendium is the digital version of the North Sea VCL. This North Sea VCL is currently being transferred to the European Digital Twin Ocean (EDITO) platform.

A Horizon Europe project – OCEANITY – was awarded recently to transform it into an interactive digital twin of the North Sea. This digital twin can be used not only to visualise pre-calculated scenarios (data layers) but also to generate what-if scenarios on the fly. That requires multiple simulation engine components and computing power that EDITO can provide.

This is therefore a win-win situation for both the North Sea Compendium and EDITO: the North Sea Compendium will acquire a continuous and free host platform with a powerful digital ecosystem around it, and EDITO will have one of the first digital applications that has been truly co-designed with high-level policymakers from the Greater North Sea countries."

The VCL technology has already been applied at Deltares in other environments, including freshwater availability on Terschelling and the urban subsurface. Currently, work is going into developing more interactivity on the spatial planning table for the Meuse Delta, where people are keen to see the effects of specific changes.