The expansion of offshore wind farms in the North Sea is making progress. But the consequences for the marine environment they are built in have not yet been fully researched.

Scientists at the Helmholtz-Zentrum Hereon have already provided valuable insights into the effects of wind farms in past studies. In their latest publication, they now show that large-scale wind farms can strongly influence marine primary production as well as the oxygen levels in and beyond the wind farm areas. Their results were published in the scientific journal Communications Earth & Environment. (photo: Nicholas Doherty)

Lasting consequences for the North Sea food web
Different wind conditions and currents, more precipitation and a changing surface climate: the effects of offshore wind farms in the North Sea are diverse and not yet fully researched. Some of them are already occurring, others are still to be expected due to the steady expansion of wind turbines into large-scale wind farms. In order to better understand them and to fill remaining knowledge gaps, a team of researchers from the Hereon Institute of Coastal Systems – Analysis and Modeling is working on different key elements of the problem.

The latest study, led by Dr Ute Daewel, now confirms impacts lead to an altered spatial distribution of marine ecosystem components. This includes the distribution of nutrients, phyto- and zooplankton as well as biomass in the sediment, the food basis for many bottom-dwelling organisms. In the model study, the team assumed the planned large-scale offshore wind farms in the North Sea. For deeper marine areas, the researchers thus found that the amount of biogenic carbon in the sediment would increase locally by 10 percent and the oxygen concentration, in an area where it is already very low, could decrease even further.

“Our results show that the extensive expansion of offshore wind farms will have a significant impact on the structuring of marine coastal ecosystems. We need to better understand these impacts quickly and also take them into account in the management of coastal ecosystems,” concludes Ute Daewel.

The news release from Helmholtz-Zentrum Hereon can be read here.

The full journal article published in Communications Earth & Environment can be read here.