Offshore Wind Energy Development Research Articles

Fisheries independent surveys in a new era of offshore wind energy development

Abstract Fisheries independent surveys require rethinking because of increasing spatial restrictions and interactions with offshore wind energy development (OWD). Fisheries, protected species, and environmental data collections have been conducted by scientific institutions to meet societal demands for food security, conservation, and other marine uses. These data collections provide information on key resource measures, essential for fisheries, protected species, and ecosystem management. With the increase in pace and magnitude of OWD's industrialization of marine waters, disruptions in these long-term time series can be expected. These disruptions will impact the ability to support current and future management goals and objectives. This paper presents an expert survey on the perceptions of OWD interactions with common survey designs and survey methodologies in Europe and the U.S., along with a selected sample of 75 fisheries independent surveys in the U.S. and Europe providing an initial assessment and description of potential impacts from OWD. About 72% of the surveys sampled record interactions with operational, planned or future OWD. Four case studies demonstrate efforts to address these interactions within European regions that have operational OWD and the U.S. where development has just begun. Finally, we make recommendations for future research important to continue meaningful scientific-based management advice.

Marine Suitability Assessment for Offshore Wind Farms’ Deployment in Thrace, Greece

The exploitation of renewable energy resources is an effective option to respond to climate change challenges. Wind energy can be exploited more efficiently and effectively than any other renewable energy source. By switching from onshore wind energy projects to offshore, the positive aspects of onshore wind energy remain and, at the same time, no valuable onshore area is occupied, while their efficiency (e.g., capacity factor) is increased. Greece has a rich wind potential and the maritime region of Thrace is one of Greece’s maritime regions with the greatest potential for the development of offshore wind energy. The aim of the present paper is to identify the most appropriate sites for the deployment of offshore wind farms in the region of Thrace. The methodology includes (i) the delineation of the study area and the definition of the support structure of the wind turbine, (ii) the identification of seven (7) exclusion and fifteen (15) assessment criteria, (iii) the suitability analysis under five different zoning scenarios (equal weight, environmental, social, techno-economic, and researchers’ subjective), and (iv) the micro siting and qualitative assessment of the most suitable sites based on energy, environmental, social, and economic criteria. The methodology is based on the combined use of Geographical Information Systems (GISs), specifically ArcGIS Desktop version 10.8.1, wind assessment software tools (WaSPs), specifically WaSP version 12.8, and multi-criteria decision-making methods. The results of the paper illustrate that the optimal suitability area that is proposed for offshore wind farm deployment is located at the easternmost end of the Greek part of the Thracian Sea. The planning and the deployment of offshore wind farm projects should follow a holistic and environmentally driven approach to ensure the integrity of all habitats and species affected.

Offshore Wind Farms and Tourism Development Relationship to Energy Distribution Justice for the Beibu Gulf, China

Energy distribution justice is of primary concern within the energy justice framework and it is crucial to increase public acceptance of offshore wind energy and further advance its development. The rapid development of offshore wind energy in China has inevitably impacted the livelihoods of coastal vulnerable groups (CVGs) engaged in fisheries and tourism in the coastal zone. While current policies often compensate for livelihood losses through cash payments, the fiscal strain caused by COVID-19 renders this approach unsustainable. Consequently, this research pioneers the exploration of Chinese tourist groups’ landscape preferences towards offshore wind farms (OWFs). This study proposes a new approach to enhance OWF landscapes for tourism development, thereby balancing the distribution of costs and benefits between CVGs and tourists. The research focuses on Beihai City in the Beibu Gulf Economic Region, utilizing a combination of Q-methodology and choice experiments that incorporates cut-offs. Answers to eighty Q-methodology questionnaires and 1324 choice experiment questionnaires are obtained. The findings indicate that this region can achieve energy distribution justice by compensating for the livelihood losses of CVGs through tourism. Contrary to traditional assumptions about wind farm noise preferences, Chinese tourists prefer proximity to OWFs, as an appropriate coastal acoustics landscape can enhance their tourism experience. In light of these findings, this paper presents policy recommendations towards energy distribution justice.

A framework for studying the effects of offshore wind energy development on birds and bats in the Eastern United States

Offshore wind energy development (OWED), while a key strategy for reducing carbon emissions, has potential negative effects to wildlife that should be examined to inform decision making and adaptive management as the industry expands. We present a conceptual framework to guide the long-term study of potential effects to birds and bats from OWED. This framework includes a focus on exposure and vulnerability as key determinants of risk. For birds and bats that are exposed to OWED, there are three main effects of interest that may impact survival and productivity: 1) collision mortality, 2) behavioral responses, including avoidance, displacement, and attraction, and 3) habitat-mediated effects to prey populations. If these OWED effects cause changes in survival and/or breeding success (e.g., fitness), they have the potential for population-level consequences, including changes in population size and structure. Understanding the influence of ecological drivers on exposure and effect parameters can help to disentangle the potential impacts of OWED from other stressors. We use this theoretical framework to summarize existing relevant knowledge and identify current priority research questions (n=22) for the eastern United States, where large-scale development of OWED is primarily in the planning and early construction phase. We also identify recommendations for study design and further prioritization of research topics.

Outlook for Offshore Wind Energy Development in Mexico from WRF Simulations and CMIP6 Projections

This study presents a comprehensive assessment of the offshore wind energy potential in Mexico across 40 years (1979–2018) of numerical simulations using the Weather Research and Forecasting (WRF) model and data from the Coupled Model Intercomparison Project Phase 6 (CMIP6). The WRF identifies three regions with moderate to good wind potential: off the north coast of Tamaulipas (Zone I), the northwest coast of Yucatan (Zone II), and the Gulf of Tehuantepec (Zone III). The analysis involves comparing 47 CMIP6 climate models with the WRF results and selecting the best performing models to obtain future projections for the short term (2040–2069) and the long term (2070–2099). Two ensemble-based strategies were implemented. The first one, which uses an intersection approach from which four CMIP6 models were considered, reveals positive percentage differences in Zone II for both future projections, especially for the long-term one. In Zones I and III, positive values are also observed near the coast, mainly for the long-term projection, but they are considerably lower compared to those in Zone II. The second ensemble strategy uses weight assignment through the Mean Absolute Percentage Error, so that a greater weight is given to the model that performed better in each particular zone, potentially providing more accurate results. The findings suggest the likelihood of increased offshore wind energy in these three zones of Mexico, for both short- and long-term future projections, with positive percentage differences of up to 10% in certain areas.

Potential impacts of offshore wind energy development on physical processes and scallop larval dispersal over the US Northeast shelf

This study examines the potential impact of offshore wind energy facilities on the local and regional circulation, stratification, and scallop larval dispersal and settlement over the U.S. Northeast continental shelf. A coupled high-resolution (up to ∼ 1.0 m), wind turbine-resolving hydrodynamical (NS-FVCOM) and scallop individual-based (Scallop-IBM) model was employed. Comparisons were made for scenarios with and without wind turbine generators (WTGs), encompassing three-dimensional flow fields, water temperature, bottom stress/vertical mixing, scallop larval dispersal, settlement, and distributions. The interaction of M2 tidal currents with monopiles generates significant horizontal flow shear on the downflow lee side. The fluid–structure interaction-induced mesoscale currents deviate substantially from the idealized flow fields examined typically in the device-scale laboratory or coarse-grid hydrodynamical models with subgrid-scale explicit parametrizations. Stratification induces noteworthy changes in the flow around individual monopiles throughout the water column, with the maximum bottom stress primarily oriented in the onshore-offshore direction and vertical eddy viscosity occurring around all directions of individual monopiles. The deployment of a WTG array amplifies offshore low-frequency subtidal flow around 40 to 50-m isobaths, forming mesoscale eddies over the shelf. This enhanced flow contributes to offshore water transport, redirecting scallop larvae toward the Nantucket Lightship Closed Area (NLCA). The accumulation of larvae in the NLCA is attributed to eddy-induced retention.

Blueprint for Blue Economy implementation

Many nations aspire to development of the Blue Economy (BE), however, the concept remains vague and there is wide need for a practical framework for implementation and evaluation of success. Based on our experience in Australia and Canada, where there is increasing BE activity, new developments being added to areas with existing uses are leading to ocean crowding and increasing the risk of undesirable outcomes. We propose a blueprint for implementation of an integrated approach to BE in an area involving four steps: 1) articulation of common BE objectives (ecological, economic, social-cultural and governance), 2) development of a governance framework in which BE objectives can be applied in management of all activities in an area, 3) a process to address conflicts, risks and trade-offs, and 4) evaluation of cumulative effects and performance of management. We illustrate the blueprint using candidate objectives relevant to the addition of offshore wind energy development. While there is a potential problem under BE for ocean crowding and for ‘plan crowding’ caused by a proliferation of sector-based planning, we suggest that there is the potential for the BE concept, properly implemented, to assist in overcoming long-standing deficiencies in existing sector-based approaches and to avoid deficiencies in planning and management associated with new or expanding BE industries. Implementation of BE will also facilitate achieving ambitious aspirations associated with national and international initiatives including the High Level Oceans Panel and Sustainable Development Goals.

Drivers of flight altitude during nocturnal bird migration over the North Sea and implications for offshore wind energy

AbstractEach year, millions of birds migrate nocturnally over the North Sea basin, an area designated for significant offshore wind energy development. Wind turbines can harm aerial wildlife through collisions and barrier effects, especially when birds fly at low altitudes below the wind turbine rotor tip. We aim to quantify seasonal and nightly differences in flight altitudes of nocturnal bird migration over the North Sea and identify how weather influences low‐altitude flight to inform wind turbine curtailment procedures for reducing bird fatalities. We used bird tracking radars at Borssele and Luchterduinen offshore wind parks, 22 and 23 km from the western Dutch coast, to monitor altitude distributions during migration. We show that median flight altitude was higher in spring compared to autumn at Borssele (spring: 285.5 m, autumn: 169.2 m; p < .001, effect size [ES] = 0.0001) and Luchterduinen (spring: 133.8 m, autumn: 126.0 m; p < .001, ES = 0.002) and below wind turbine rotor tip in both seasons. On most nights in both seasons, the majority of migrants flew predominantly at low altitudes, except for intense migration nights in spring in Borssele where, on 87% of these nights, migration mainly occurred at high altitudes. The most important predictors of low‐altitude migration in both seasons were day of year and wind assistance. Birds chose altitudes with the most favorable wind conditions for migration in both seasons. The relationship between day of year and low‐altitude migration fraction suggests that different species migrate at different altitudes. In spring, birds were flying lower at the beginning and the end of the night, reflecting departures and arrivals of birds, while radar location in autumn was a good predictor of low‐altitude flights, indicating that different local migratory axes have distinct altitude distributions. Our findings suggest that mitigation measures offshore may be more effective during autumn than spring, especially on nights with more supportive wind conditions at altitudes below 300 m.

Life cycle environmental analysis of offshore wind power: A case study of the large-scale offshore wind farm in China

China's decarbonization is indispensable for the large-scale utilization of renewable energy. In this process, the development of offshore wind energy has become an important support, because in the eastern region of China, especially the coastal areas, there's the most load requirements but limited onshore renewable resources. Under the goals of both carbon neutral and sustainable development, however, there's still a research gap in evaluating the environmental impacts of large-scale offshore wind plants in China. In this study, the research performed a comprehensive process-based life cycle environmental analysis of a large-scale (400 MW) offshore wind farm with large wind turbine units (5 MW) in China. Global Warming Potential is 25.73 g CO2-eq/kWh and greenhouse gas payback time is calculated as 12.05 months. Fossil fuel consumption amounts to 0.31 MJ/kWh with an energy payback period of 25.56 months. Material resources and ecotoxicity to freshwater need more attention with the values of 1.68 CTUe/kWh and 3.32 10−6 kg Sb-eq/kWh, respectively. The manufacturing stage contributes most to all the impacts examined. The disposal and recycling process shows significant environmental benefits for most impacts but exerts burdens on the particulate matter. Focusing on Global Warming Potential, the wind turbine generation set has the highest effect, among which the blades contribute 73.2% of it. Further, the evolution of electricity and heating mix of China and use of biomass-based precursors could decrease 57% of the blades' greenhouse gas emissions in 2050. This study could provide guidance on the sustainable design and policy-making of offshore wind farms.

Spatial distribution and long-term trend of wind energy in the Northwest Pacific Ocean

Abstract: Given the threat of fossil fuel depletion, it is essential to proactively strive for carbon neutrality and promote clean, low-carbon and efficient energy use. This study used ERA5 reanalysis data to assess wind energy resources in the Pacific Northwest region. By analyzing key indicators such as wind power density, effective wind speed occurrence, and energy level occurrence, climate statistics and Empirical Orthogonal Function analysis (EOF) were used to examine the spatial distribution and long-term trend of offshore wind energy resources in the Northwest Pacific. The results suggest that there are abundant wind energy resources in this region, which are beneficial for the development of offshore wind energy. The rich areas are the East China Sea, Taiwan islands and reefs in the South China Sea and east of Japan, with prevailing wind power density (500 ∼ 2500 W/m2) and effective wind speed occurrence (80–90%) and energy level occurrence (60% ∼ 90%). Offshore wind energy resources in the Pacific Northwest are more abundant in fall and winter than in summer. The time coefficient of the first mode shows that the offshore wind energy in the Northwest Pacific has no obvious change trend, and the wind energy resources are relatively stable.

Offshore wind energy potential along the Indian Coast considering ecological safeguards

This study focuses on assessing the offshore wind energy potential along the Indian Coast over a 10-year period (2005–2014) using high-resolution data from the simulation of the Weather Research and Forecasting (WRF) model. The predicted wind fields are utilized to identify potential sites, estimate offshore wind technical potential at different depths (ranging from 30 to 200 meters), and develop wind energy blocks within the Indian Exclusive Economic Zone. To ensure environmental protection, environmentally sensitive areas have been excluded from the offshore wind potential sites. The gross technical offshore wind potential was estimated to be 3941 GW within depths of 30–200 meters, excluding environmentally sensitive areas within the 0 to 30-m depth range. High-potential sites have been identified in the coastal states of Gujarat, Maharashtra, Kerala, and Tamil Nadu. The environmental offshore wind potential across these identified sites (feasible OWE sites) along the Indian coast is estimated at 432.34 GW within the 30 to 200-m depth range (at 140 m AGL).According to the report by the Central Electricity Authority (CEA), the predicted offshore wind power has the potential to significantly contribute to the country's total electrical power requirement for 2020–21. This study encourages exploration of offshore wind energy possibilities along the Indian coast and highlights the management challenges at suitable sites, including addressing potential conflicts between offshore wind energy development and other marine uses. The findings of this study can assist in the assessment of offshore wind resources and provide decision-makers with scientific evidence for the development of offshore wind energy in India, while also considering the management and conservation of marine ecosystems.

Uncertainty quantification for dynamic responses of offshore wind turbine based on manifold learning

Offshore wind turbines (WTs) are crucial in offshore wind energy development. However, the dynamic responses of WTs are subject to significant uncertainties which are usually not properly considered. To the end, this paper proposes an efficient method for quantifying the uncertainties in WTs' dynamic responses based on cumulative distribution function (CDF)-manifold learning. First, a probabilistic model is developed to represent the environmental parameters and sampling for aerodynamic-hydraulic-servo-elastic simulations. Then, the CDF is obtained by statistically analyzing the simulated data. To tackle the higher dimensionality resulting from discretizing the CDF, a manifold learning-based approach is subsequently proposed to reduce its dimensionality and obtain a manifold space. Furthermore, a mapping relation is established between the environmental parameters and the low-dimensional data to efficiently obtain the response CDF under different environmental parameters, leading to the construction of a probability box (P-box) model. To demonstrate the effectiveness of the proposed method, the National Renewable Energy Laboratory (NREL) 5 MW offshore WT on an Offshore Code Comparison Collaboration (OC3) monopile is selected as a case study and analyzed accordingly. The results show P-box models of seven WT responses and validate the effectiveness of the proposed method.

Hatchery capacity needed to support large‐scale Atlantic surfclam fishery enhancement

AbstractFishery enhancement methods are being explored globally to sustain commercial and recreational fisheries through improving the productivity and management of marine populations impacted by anthropogenic stressors. It is expected that access to important Atlantic surfclam fishing grounds will be limited or lost due to growing overlap with offshore wind energy development. This study explores the economic viability of large‐scale hatchery production to improve fishery access and potentially offset additional costs, reduced revenues and potential job losses associated with the displacement of the fishing fleet. Reports and primary literature were used to understand the growth and survival of Atlantic surfclams in hatchery and nursery settings to calculate the scale of hatchery efforts needed to support one million (1M) bushels of fishery‐sized clams (>120 mm). Data on labour, energy, construction and material inputs and costs for hatchery and nursery production were gathered by analysing available literature and information provided by hatchery managers, researchers and others knowledgeable about shellfish hatchery production. A techno‐economic cost model and Monte Carlo analyses were employed to explore average costs and their variability. This study suggests that 374M–2.1B Atlantic surfclams are needed at the end of the hatchery stage to produce 1M bushels of market‐sized product. Total production costs range from $3.7 to $15.1M, including $2.9–$13.3M in hatchery costs and $800K–$1.9M in nursery costs. Under current market conditions, where Atlantic surfclams regularly sell for $14–$17/bushel, this analysis suggests that hatchery production could be considered a viable fishery enhancement method that supports human access to the fishery, though several additional questions remain.

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.

EUROPEAN OFFSHORE NETWORK WITH WIND POWER PLANTS

Problems The growth of electricity consumption and the change in climatic conditions present society with the challenge of ensuring sustainable and ecologically clean electricity production. For many countries, especially in the European Union, the transition to sustainable and ecologically clean energy sources has become a priority.
 Objective A general overview and analysis of trends in the development of the network of offshore wind power plants located in the open sea on the continental shelf of European countries
 Methodology of implementation The strategy for the development of a single European offshore network with wind power plants was used for research. The study of the effectiveness and advantages of offshore power plants was carried out in the variability of the advanced countries of the European Union..
 Results An overview of the electric power industry of European countries that pursue an active policy in the field of offshore energy is given. The statistics on the generation of wind energy, the number and development of wind turbines in Europe are given. The main projects that have been implemented or are in the process of preparation have been considered. An analysis of the measures introduced by the European Union to increase the use of wind energy and reduce dependence on traditional energy sources and achieve carbon neutrality was performed.
 Conclusions The European offshore network with wind power plants has become an important component of sustainable energy development in the region. Statistics on the development of offshore wind energy indicate that European countries are actively working on the development of this sector, investing significant efforts and resources.

Sustainability conflicts in the blue economy: planning for offshore aquaculture and offshore wind energy development in Norway

Blue economy developments entail an industrialization of the world’s ocean and coastal areas, placing growing pressures on the marine environment and ecosystems. Moreover, the competition for ocean space and resources increases the likelihood for social conflicts. Marine spatial planning has been presented as a tool that can avoid or mitigate conflicts. However, there is a need for a more thorough analysis of the conflicts linked to the blue economy. The objective of this paper is to analyze characteristics of blue economy conflicts and how they are shaped by the institutional context and sustainability discourses. This study also explores perspectives on conflict management and pathways toward sustainable transformations in marine planning. Empirically, we use two case studies of blue growth industries in Norway: (1) offshore wind energy development and (2) offshore aquaculture development. Through these cases, we take a close look at the established principles and procedures which regulate conflicts. Our study shows how current blue economy conflicts are framed and handled through institutionalized practices of conflict management. Our findings are twofold. First, blue economy conflicts are not easily categorized through common conflict typologies (i.e., user-user, user-environment) but increasingly appear to be sustainability conflicts in which all actors use sustainability as a frame of reference for discussing possible and desirable futures. Second, conflicts are not necessarily a negative social process. In fact, conflicts often uncover unsustainable practices and create potential positive pathways for sustainable transformations.

Leveraging data from a private recreational fishing application to begin to understand potential impacts from offshore wind development

Abstract The development of offshore wind energy in the United States necessitates a sound understanding of trade-offs across ocean uses. Location data on private recreational fishing have been a glaring gap in understanding how society uses marine resources, despite its economic importance. In this study, we use a novel data set to start to fill that knowledge gap. We employ a flexible restricted likelihood spatial scan statistic on data from Fish Rules, a smartphone application, which provides georeferenced species-level regulations, to understand whether species-level data of user queries are clustered spatially. Originally developed for epidemiological studies of disease clusters, the flexible scan statistic employed in this study uses a Bernoulli likelihood ratio test to assess the size, number, and significance of clusters in presence/absence data for recreational species. We use a second data set of known fishing locations to validate that the clusters identify private recreational fishing activity. We then discuss the analysis in the context of wind lease areas in the region, highlighting its value in supporting management decision-making. The results suggest that Fish Rules data identify areas with a high likelihood of being private angler fishing locations and can assess differential impacts of offshore wind development on private recreational fishing activities.

Multispecies blue justice and energy transition conflict: examining challenges and possibilities for synergy between low-carbon energy and justice for humans and nonhuman nature

This paper explores deep insights into sustainability transition tensions and pathways in terms of place-based conflict and potential for synergies between offshore wind energy (OWE) development and justice for humans and nonhuman nature. Specifically, we build a capability and recognition-based multispecies blue justice framework that at once centers ecological reflexivity (i.e., environmental awareness-raising, proxy representation of nature, and institutional recognition and protection of rights of nature and human-nature relationality), decenters anthropocentric frames of justice, and sheds light on injustices, human and nonhuman that climate and energy transitions may create or reinforce. This framework then informs analysis of a sustainability transition conflict, specifically a longstanding OWE conflict on Hiiumaa island, Estonia. This analysis unravels justice concerns, human and nonhuman, raised by proxy representatives of nature (i.e., grassroots actors and environmental stewards), the knowledge contestations involved, and the resolution measures undertaken thus far. Next, we discuss the possible transformative role of the OWE conflict, including how a Supreme Court ruling invalidating the OWE plan has fostered reflexive planning and may have set a legal precedent that may have human and nonhuman justice implications for the handling of future planning cases. We then highlight remaining challenges for socially and ecologically responsive OWE deployment. These include the judicial non-recognition of nature’s right as well as environmental values and sociocultural ties to nature as rights worth protecting, and the likely effects that formalization of European Union ambitions to speed-up and ramp-up renewable energy could have locally. These include prospects for environmental stewards and ocean defenders to steer nature-positive, people-centered energy transitions. Last, we propose conditions for enhanced multispecies justice, including how formal interventions (e.g., law) and informal practices (e.g., negotiation, awareness-raising) can be harnessed to unlock productive conflict and align energy transitions with the norms of justice, human and nonhuman.

Investigation of potential metal emissions from galvanic anodes in offshore wind farms into North Sea sediments

To evaluate potential metal emissions from offshore wind farms (OWFs), 215 surface sediment samples from different German North Sea OWFs taken between 2016 and 2022 were analyzed for their mass fractions of metals and their isotopic composition of Sr. For the first time, this study provides large-scale elemental data from OWFs of the previously proposed galvanic anode tracers Cd, Pb, Zn, Ga and In. Results show that mass fractions of the legacy pollutants Cd, Pb and Zn were mostly within the known variability of North Sea sediments. At the current stage the analyzed Ga and In mass fractions as well as Ga/In ratios do not point towards an accumulation in sediments caused by galvanic anodes used in OWFs. However, further investigations are advisable to evaluate long-term effects over the expected lifetime of OWFs, especially with regard to the current intensification of offshore wind energy development.

Effect of sea states on the wind velocity fluctuations near the surface under near-neutral conditions

This study examines the effect of sea states on wind velocity fluctuations in the longitudinal direction near the sea surface under near-neutral stratification, characterized by inverse wave age. The analysis is based on wind and wave data collected from a discus buoy measurement off the coast of Taiwan in the Taiwan Strait. It is observed that wind waves and swells modify the overlying turbulence structure differently. In particular, wind-swell coupling results in greater variations and values of the scaled velocity standard deviation and turbulence intensity with increasing wind speed, as well as a more pronounced peak in the scaled wind velocity spectrum compared to pure wind sea conditions. The spectral shapes averaged for pure wind sea and swell conditions are described by a plateau followed by a wave-induced peak in the intermediate-frequency range. These features suggest that near-surface turbulence is driven by eddy impingement on the sea surface, associated with wave-induced fluctuations in the lower part of the eddy surface layer. The study has practical applications in evaluating the wind loads on offshore structures, particularly in the context of offshore wind energy development.