This is an evidence base of available literature on the impacts of offshore wind farm (OWF) developments and the outcomes for marine ecosystem services. The evidence was collated through a systematic search of global primary literature (also known as peer-reviewed or published literature) and UK grey literature regarding the impacts of OWF developments (the scope for including global grey literature was unfeasible). Grey literature refers to multiple types of report or document, and is defined as: "information produced on all levels of government, academia, business and industry in electronic and print formats not controlled by commercial publishing" i.e. where publishing is not the primary activity of the producing body (ICGL, 1997). Data was extracted from each evidence source, for each subject or marine ecosystem component that was impacted by the OWF development, the phase of development, the specific pressure and other relevant information about the wind farm or location. Expert judgement was used to map each piece of evidence for impacts on the marine environment according to CICES (Common International Classification of Ecosystem Services) or MEA (Millenium Ecosystem Assessment) and other published classification systems for ecosystem services (Ryfield et al., 2019; Hooper et al., 2020). The dataset was created to provide a central evidence base of available primary and grey literature regarding the impacts of OWF developments (for construction, operational and decommissing phases) on ecosystem service outcomes in the marine environment. The primary literature represents a global semi-systematic search, while the grey literature is restricted to a semi-systematic search for reports and documents from the UK (that also include wind farms in adjacent waters). The database provides a comprehensive list of available literature on this topic, and it enables the assessment and comparison of the evidence for enviromental impacts and ecosystem service outcomes between primary and grey literature sources. This will be critical for marine policy makers when gathering evidence for future OWF developments and advances understanding of the impacts and trade-offs associated with OWF and ecosystem services. A tool (currently in development by Plymouth Marine Laboratory) will improve accessibility of the data for this purpose. This research was funded by the UKERC Phase 4 research programme.
