Abstract
An initial explorative study has indicated that a future large-scale increase of offshore wind farms may have ecosystem effects that are at present either not occurring or are not relevant at the scale of an ecosystem. Such changes in the physical functioning of the North Sea may influence the foundation of the food web: primary production, which in turn will have consequences for all higher trophic levels. This study presents a first attempt to quantify the physical and ecological effects, using a new suite of ecosystem models, to assess which processes are relevant in which parts of the North Sea (a bottom up approach). Another part of the wider project assesses the best methodologies to ascertain in the near future what the consequences are of these changes on species of high conservation status (top-down approach).