Sustainable co-location solutions for offshore wind farms and fisheries need to account for socio-ecological trade-offs

Ecological impacts of floating offshore wind on marine mammals and associated trophic interactions: current evidence and knowledge gaps

Floating offshore wind is expected to expand globally into further offshore, deeper and highly productive shelf seas to utilise increased and more consistent wind energy. Marine mammals represent mobile species that connect across regions and can indicate wider ecosystem changes. To date, only a handful of ecological impact studies have been conducted at floating offshore wind farms, due to the infancy of the technology and small numbers of operational sites. Understanding how floating offshore wind could alter ecosystem functions and impact species at individual and population levels will be essential to mitigate potential negative ecological impacts as the sector expands. Currently, numerous floating offshore wind sites are planned or already in development. Therefore, evaluating current knowledge and remaining knowledge gaps will benefit future projects in assessing ecological impacts and determining where additional research should be conducted. This review summarises the positive and negative ecological impacts that have been previously highlighted as potential impacts from floating offshore wind, focusing on marine mammals, whilst also considering prey and broader trophic interactions. Current studies at operational floating offshore wind sites are summarised and discussed in context of observed and/or anticipated impacts. Finally, key outstanding research areas are suggested in relation to each impact.

Mapping the value of commercial fishing and potential costs of offshore wind energy on the U.S: West Coast: Towards an assessment of resource use tradeoffs

The West Coast of the U.S. has a vast offshore wind energy (OWE) electricity generation potential with value on the order of billions of USD, and pressure is mounting to develop large OWE projects. However, this seascape has numerous existing resource extraction uses, including a multi-billion dollar commercial fishing industry, which create the potential for conflict. To date, spatially explicit comparisons of OWE and commercial fisheries value have not been done, but are essential for marine spatial planning and for investigating the tradeoffs of OWE development on existing marine uses. In this analysis, we generate maps of OWE levelized cost of energy and of total economic activity generated by the top eight commercial fishing targets that account for the vast majority (~84%) of landed revenue off the U.S. West Coast. We quantify spatial overlap between these two ocean uses and use multiobjective optimization to develop tradeoff frontiers to investigate implications for both sectors from established state goals or mandates for OWE power generation capacity. There are clear differences in the exposure of each fishery in their traditional fishing grounds as a function of differing OWE capacity goals and outcomes vary depending on whether OWE development goals are achieved at a state-by-state level or a region-wide level. Responsible siting of OWE projects includes careful consideration of existing commercial fishing activities, and responsible transition to renewable energies on the West Coast and elsewhere accounts for the socio-economic consequences of the total economic activity associated with each fishery.

Environmental implications of future offshore renewable energy development in Aotearoa New Zealand

Global climate mitigation efforts seeking to reduce greenhouse gas emissions require more renewable energy generation and utilisation. In Aotearoa New Zealand there are initiatives underway to develop offshore wind, or in the future, arrays of tidal turbines or wave energy converters, as a new energy resource. Here we synthesise available knowledge from international developments in offshore windfarm installations and discuss in a local Aotearoa New Zealand context. Aspects described include habitat modification, consequences of physical water column changes, and effects on benthic organisms, fish and fisheries, seabirds and marine mammals. Importantly, there is a need to adhere to Te Tiriti o Waitangi which defines Māori sovereign rights and expectations in terms of guardianship of resources (kaitiakitanga). Based on recent regulatory applications in marine spatial planning, where developments have been subject to the precautionary principle for environmental impacts, comprehensive environmental information will be critical for obtaining approval to proceed. The present synthesis identifies environmental pressure-points, footprints, and knowledge gaps, such as New Zealand-specific seabird and marine mammal behaviour and discusses potential opportunities to leverage the positive impacts of marine renewable energy developments.

Operationalizing a fisheries social-ecological system through a Bayesian belief network reveals hotspots for its adaptive capacity in the southern North sea

Fisheries social-ecological systems (SES) in the North Sea region confront multifaceted challenges stemming from environmental changes, offshore wind farm expansion, and marine protected area establishment. In this paper, we demonstrate the utility of a Bayesian Belief Network (BN) approach in comprehensively capturing and assessing the intricate spatial dynamics within the German plaice-related fisheries SES. The BN integrates ecological, economic, and socio-cultural factors to generate high-resolution maps of profitability and adaptive capacity potential (ACP) as prospective management targets. Our analysis of future scenarios, delineating changes in spatial constraints, economics, and socio-cultural aspects, identifies factors that will exert significant influence on this fisheries SES in the near future. These include the loss of fishing grounds due to the installation of offshore wind farms and marine protected areas, as well as reduced plaice landings due to climate change. The identified ACP hotspots hold the potential to guide the development of localized management strategies and sustainable planning efforts by highlighting the consequences of management decisions. Our findings emphasize the need to consider detailed spatial dynamics of fisheries SES within marine spatial planning (MSP) and illustrate how this information may assist decision-makers and practitioners in area prioritization. We, therefore, propose adopting the concept of fisheries SES within broader integrated management approaches to foster sustainable development of inherently dynamic SES in a rapidly evolving marine environment.

Techno-economic assessment of potential zones for offshore wind energy: A methodology

This work presents a methodology for the techno-economic assessment and comparison of potential zones for the development of offshore wind energy. The methodology is illustrated through a case study in North Spain, using the high-potential zones designated by the Spanish government. The main elements considered include the bathymetry (water depths), energy production and total working hours based on the wind climate, maintenance windows based on the wave climate, and distance to selected port facilities that can accommodate the installation and operational and maintenance phases of an offshore wind farm. An interesting dichotomy arises moving from west to east along N Spain - energy production and working hours decrease, but maintenance windows increase. Given that both aspects play a role in the costs of an offshore wind project, pondering them adequately is crucial, and the selection of a particular zone for development may depend on project-specific cost models. Water depths may preclude the installation of bottom-fixed structures in certain areas; importantly, they may also represent a constraint for the deployment of certain floating concepts, particularly in the high-potential zones of the Cantabrian Sea. Finally, ports capable of servicing the offshore wind farms are identified and distances to all high-potential zones, calculated. By examining the unique properties of the high-potential zones, this methodology, which can be applied to other regions of interest for offshore wind, provides valuable insights into the advantages and challenges of offshore wind development at each site and thereby contributes to informed decision-making.

Framing future trajectories of human activities in the German North Sea to inform cumulative effects assessments and marine spatial planning

The global industrialization of seascapes and climate change leads to an increased risk of severe impacts on marine ecosystem functioning. While broad scale spatio-temporal assessments of human pressures on marine ecosystems become more available, future trajectories of human activities at regional and local scales remain often speculative. Here we introduce a stepwise process to integrate bottom-up and expert-driven approaches for scenario development to inform cumulative effects assessments and related marine spatial planning (MSP). Following this guidance, we developed optimistic, realistic, and pessimistic scenarios for major human pressures in the German North Sea such as bottom trawling, offshore wind, nutrient discharge, and aggregate extraction. The forecasts comprise quantitative estimates in relation to spatial footprint, intensity, and technological advancements of those pressures for the years 2030 and 2060. Using network analyses, we assessed interactions of the current and future trajectories of pressures thereby accounting for climate change and the growing need for marine conservation. Our results show that future scenarios of spatial distributions could be developed for activities that are spatially refined and included in the current MSP process. Further our detailed analyses of interdependencies of development components revealed that forecasts regarding specific targets and intensities of human activities depend also strongly on future technological advances. For fisheries and nutrient discharge estimates were less certain due to critical socio-ecological interactions in the marine and terrestrial realm. Overall, our approach unraveled such trade-offs and sources of uncertainties. Yet, our quantitative predictive scenarios were built under a sustainability narrative on a profound knowledge of interactions with other sectors and components in and outside the management boundaries. We advocate that they enable a better preparedness for future changes of cumulative pressure on marine ecosystems.

Impacts of climate change on wind energy potential in Australasia and South-East Asia following the Shared Socioeconomic Pathways

Wind energy is poised to play a major role in the energy transition. Fluctuations in global atmospheric circulation are expected as a result of climate change, and wind projections based on the most up-to-date scenarios of climate change, the Shared Socioeconomic Pathways (SSPs), anticipate significant changes in wind energy potential in many regions; so far, these changes have not been studied in Southeastern Asia and Australasia, a region with notable wind energy potential. This work investigates the evolution of wind power density and its temporal variability considering the latest scenarios of climate change, the SSPs. More specifically, two scenarios are considered, SSP2-4.5 and SSP5-8.5, corresponding to moderate and high emissions, respectively. As many as 18 global climate models are considered and compared against past-present data, and those that perform best are retained to build a large multi-model ensemble. The results show that projected changes in mean wind power density at the end of the 21st century are of little significance (typically below 5 %); nevertheless, this value can be far surpassed locally. In certain areas (e.g., Vietnam, Borneo) and seasons, remarkable changes in wind power density (exceeding 150 %) are anticipated. Typically, mean values and temporal variability changes are greater in the high-emissions scenario, however, seasonal variability is projected to be more pronounced in the moderate-emissions scenario. These effects of climate change on wind energy potential must be taken into account in the development of wind power in the region, for they will affect the energy production and, therefore, the economic viability of wind farms - not least in those areas where drastic changes are projected.

Climate change impacts on wind energy resources in North America based on the CMIP6 projections

The mid- and long-term evolution of wind energy resources in North America is investigated by means of a multi-model ensemble selected from 18 global climate models. The most recent scenarios of greenhouse gases emissions and land use, the Shared Socioeconomic Pathways (SSPs), are considered - more specifically, the SSP5-8.5 (intensive emissions) and SSP2-4.5 (moderate emissions). In both scenarios, onshore wind power density in the US and Canada is predicted to drop. Under SSP5-8.5, the reduction is of the order of 15% overall, reaching as much as 40% in certain northern regions - Quebec and Nunavut in Canada and Alaska in the US. Conversely, significant increases in wind power density are predicted in Hudson Bay (up to 25%), Texas and northern Mexico (up to 15%), southern Mexico and Central America (up to 30%). As for the intra-annual variability, it is poised to rise drastically, with monthly average wind power densities increasing up to 120% in certain months and decreasing up to 60% in others. These changes in both the mean value and the intra-annual variability of wind power density are of consequence for the Levelised Cost of Energy from wind, the planning of future investments and, more generally, the contribution of wind to the energy mix.

Bright spots as climate-smart marine spatial planning tools for conservation and blue growth

Marine spatial planning that addresses ocean climate-driven change ('climate-smart MSP') is a global aspiration to support economic growth, food security and ecosystem sustainability. Ocean climate change ('CC') modelling may become a key decision-support tool for MSP, but traditional modelling analysis and communication challenges prevent their broad uptake. We employed MSP-specific ocean climate modelling analyses to inform a real-life MSP process; addressing how nature conservation and fisheries could be adapted to CC. We found that the currently planned distribution of these activities may become unsustainable during the policy's implementation due to CC, leading to a shortfall in its sustainability and blue growth targets. Significant, climate-driven ecosystem-level shifts in ocean components underpinning designated sites and fishing activity were estimated, reflecting different magnitudes of shifts in benthic versus pelagic, and inshore versus offshore habitats. Supporting adaptation, we then identified: CC refugia (areas where the ecosystem remains within the boundaries of its present state); CC hotspots (where climate drives the ecosystem towards a new state, inconsistent with each sectors' present use distribution); and for the first time, identified bright spots (areas where oceanographic processes drive range expansion opportunities that may support sustainable growth in the medium term). We thus create the means to: identify where sector-relevant ecosystem change is attributable to CC; incorporate resilient delivery of conservation and sustainable ecosystem management aims into MSP; and to harness opportunities for blue growth where they exist. Capturing CC bright spots alongside refugia within protected areas may present important opportunities to meet sustainability targets while helping support the fishing sector in a changing climate. By capitalizing on the natural distribution of climate resilience within ocean ecosystems, such climate-adaptive spatial management strategies could be seen as nature-based solutions to limit the impact of CC on ocean ecosystems and dependent blue economy sectors, paving the way for climate-smart MSP.