Assessments of global wave power have been receiving increasing attention currently; however, a characterization of the global resources that holistically consider the different temporal scales that influence wave climate (monthly and seasonal, interannual and long-term) is still lacking. Moreover, the debate around the global figure of available resource is still widely open. This study provides a new global wave power assessment using a dataset that covers the period from 1948 to 2008, which was corrected using altimetry data and validated with buoys in terms of wave power. This study characterizes the mean wave power globally as well as its monthly and seasonal variability. Furthermore, it provides a link with the most relevant climate indices globally. The effect of the interannual variability is especially noteworthy for the Northern Hemisphere, where the seasonality is strongest. Additionally, we detect decadal long-term changes and determine that natural variability could explain a few of the differences found between decades. Lastly, we provide an assessment of the global theoretical wave power that covers the last six decades, compare approaches and estimates, and discuss factors of discrepancy. The global offshore wave power is estimated at 32,000 TW h/yr, which is reduced to 16,000 TW h/yr when considering the direction of the energy. The historical average change is 580 TW h/decade. Our results indicate that the global natural variability could be a more relevant factor in the lifetime of wave farms than the historical long-term changes in wave energy.
It is widely acknowledged that many renewable energy technologies cannot (yet) compete with incumbent (fossil fuel) options e.g. in terms of price. Transitions literature argues that sustainable innovations can nevertheless break out of their ‘niches’ if properly shielded, nurtured and empowered. Most studies using this perspective have focused on how innovation champions engage in shielding, nurturing and empowering (SNE) activities: none have so far focused specifically on the role that policy plays in relation to these three processes. This paper therefore aims to analyze the way in which policy constrains and enables the shielding, nurturing and empowering of renewable energy innovations. To do so, it presents a qualitative review of the development of offshore wind power (OWP) in The Netherlands over the past four decades. Based on interpretation of a wide variety of written sources (academic histories, reports, policy documents, parliamentary debate transcripts, news media) and nine semi-structured interviews, it discerns six periods of relative stability in the history of Dutch offshore wind. It then analyzes the effects of various policies on the shielding, nurturing and empowering of offshore wind in these periods. The paper contributes to transitions literature (1) by providing an analysis of how policies can enable and constrain the shielding, nurturing and empowering of renewable energy innovations, and (2) by bringing together, for the first time, fragmented accounts of the surprisingly long history of Dutch offshore wind development and implementation. Both contributions are timely, given the recent reprioritization of OWP on the Dutch policy agenda.
For marine energy to be truly sustainable, its social and ecological impacts must be identified and measures by which to mitigate adverse effects established before devices are deployed in large arrays. To inform future research and encourage environmentally-sensitive developments, this review aims to identify the most significant social and ecological issues associated with wave and tidal current energy generation. Modifications to wave climates, flow patterns, and marine habitats, particularly through increased underwater noise and collision risk, are identified as key ecological issues. Social acceptance of renewable energy is found to be closely linked to the level of stakeholder involvement and the public perception of renewable energy. The review concludes with a call for a more strategic and collaborative research effort between developers, academia, and the public sector to improve environmental monitoring standards and best practices for device and array design.
Meeting the United States׳ offshore renewable-energy goals for 2030 necessitates deploying approximately 9000 wind turbines along U.S. coastlines. Because siting bottom-mounted turbines in most nearshore coastal zones is either impractical or politically difficult, turbine developers are testing floating-platform turbine technologies for deeper waters. Deepwater, floating-platform turbines have the advantages of being sited in the highest quality winds farther offshore, movable if desired, and located beyond the horizon, out of sight from shore. This paper reports on conversations with 103 coastal stakeholders at community meetings regarding development and testing of floating turbines off the coast of Maine, U.S.A. Using naturalistic field methods, this essay reports common questions and concerns of commercial lobstermen, fishermen, and coastal civic leaders. Early-stage conversations suggest that once coastal community members understand the benefits and impacts of wind farm development on their quality of life, many share specific preferences for where offshore developments could be located. Citizens׳ remarks are sophisticated, nuanced, and innovative and include robust ideas for pairing turbine siting with fishery conservation. Findings imply that when looking to site offshore turbines in public, multiple-use ocean spaces, developers, planners, and coastal communities should engage early and often in two-way conversation rather than one-way outreach.
A conceptual framework was developed for assessing the sub-level of protection in 185 multiple-use marine protected areas (MPAs) in the English Channel through a survey on management effort. Data were retrieved from 153 MPAs: 4.56% were assigned low management effort, 83.70% were assigned medium management effort, and 11.76% were assigned high management effort. Overall, French MPAs performed better in terms of management effort than English MPAs and lack of consistency in ratings by different management bodies in England was found. Lack of correlation between management effort and conservation status within an available subset of 13 MPAs suggests that management may not be as influential a factor for the effective conservation of MPAs, especially in marine environments under heavy human pressure such as the English Channel. It is suggested that MPAs in such areas may therefore require an upgrade of their legal level of protection to be effective.
Despite recent efforts to increase the global coverage of marine protected areas (MPAs), studies investigating the effectiveness of marine protected areas within temperate waters remain scarce. Furthermore, out of the few studies published on MPAs in temperate waters, the majority focus on specific ecological or fishery components rather than investigating the ecosystem as a whole. This study therefore investigated the dynamics of both benthic communities and fish populations within a recently established, fully protected marine reserve in Lamlash Bay, Isle of Arran, United Kingdom, over a four year period. A combination of photo and diver surveys revealed live maerl (Phymatolithon calcareum), macroalgae, sponges, hydroids, feather stars and eyelash worms (Myxicola infundibulum) to be significantly more abundant within the marine reserve than on surrounding fishing grounds. Likewise, the overall composition of epifaunal communities in and outside the reserve was significantly different. Both results are consistent with the hypothesis that protecting areas from fishing can encourage seafloor habitats to recover. In addition, the greater abundance of complex habitats within the reserve appeared to providing nursery habitat for juvenile cod (Gadus morhua) and scallops (Pecten maximus and Aequipecten opercularis). In contrast, there was little difference in the abundance of mobile benthic fauna, such as crabs and starfish, between the reserve and outside. Similarly, the use of baited underwater video cameras revealed no difference in the abundance and size of fish between the reserve and outside. Limited recovery of these ecosystem components may be due to the relatively small size (2.67 km2) and young age of the reserve (<5 years), both of which might have limited the extent of any benefits afforded to mobile fauna and fish communities. Overall, this study provides evidence that fully protected marine reserves can encourage seafloor habitats to recover, which in turn, can create a number of benefits that flow back to other species, including those of commercial importance.
The selection of spawning habitat of a population of Octopus vulgaris that is subject to a small-scale exploitation was studied in the Cíes Islands within the National Park of the Atlantic Islands of Galicia (NW Spain). The technique used was visual censuses by scuba diving. We conducted 93 visual censuses from April 2012 to April 2014. The total swept area was 123.69 ha. Habitat features (season, depth, zone, bottom temperature, swept area, bottom substrate type, and creels fishing impact) were evaluated as predictors of the presence/absence of spawning dens using GAM models. O. vulgaris has a noteworthy preference for spawning in areas with hard bottom substrate and moderate depth (approximately 20 m). The higher density of spawning dens (1.08 ha−1) was found in a surveyed area of 50.14 ha located in the northeastern part of the northern Cíes Island. We propose to protect the area comprised from Punta Escodelo to Punta Ferreiro between 5 and 30 m depth. This area has a surface of 158 ha equivalent to 5.98% of the total marine area of the Cíes islands. The strengths and weaknesses of a management strategy based on the protection of the species’ spawning habitat are discussed.
A key component of ecosystem-based fisheries management (EBFM) is explicit consideration of trade-offs. Ecosystem models can be used to quantify trade-offs and focus discussion around objectives. Given large structural uncertainties inherent in ecosystem models, however, comparative approaches are recommended to identify results that are robust to model formulation. We developed ecosystem models of the continental shelf and slope of New South Wales, Australia, using two ecosystem modelling frameworks, Atlantis and Ecopath with Ecosim. The models were calibrated to emulate large-scale changes in ecosystem structure between 1976 and 1996, as predicted by data from fishery-independent trawl surveys. Calibrated models were projected forward under a range of “optimal” fishing efforts designed to achieve economic, conservation or biodiversity objectives. While there were large differences in model predictions for individual species, the models gave very similar qualitative results when ranking fishing policies and describing trade-offs. Our results illustrate the importance of identifying fishery objectives before build-up of fleet capacity, and the need to consider trade-offs when simultaneously stating multiple ecosystem-level goals. Our finding that structurally-distinct ecosystem models can provide consistent qualitative advice highlights the capacity of ecosystem models for informing strategic management questions, even in the presence of considerable uncertainty in ecosystem-level processes.
Accurate wetland maps are a fundamental requirement for land use management and for wetland restoration planning. Several wetland map products are available today; most of them based on remote sensing images, but their different data sources and mapping methods lead to substantially different estimations of wetland location and extent. We used two very high-resolution (2 m) WorldView-2 satellite images and one (30 m) Landsat 8 Operational Land Imager (OLI) image to assess wetland coverage in two coastal areas of Tampa Bay (Florida): Fort De Soto State Park and Weedon Island Preserve. An initial unsupervised classification derived from WorldView-2 was more accurate at identifying wetlands based on ground truth data collected in the field than the classification derived from Landsat 8 OLI (82% vs. 46% accuracy). The WorldView-2 data was then used to define the parameters of a simple and efficient decision tree with four nodes for a more exacting classification. The criteria for the decision tree were derived by extracting radiance spectra at 1500 separate pixels from the WorldView-2 data within field-validated regions. Results for both study areas showed high accuracy in both wetland (82% at Fort De Soto State Park, and 94% at Weedon Island Preserve) and non-wetland vegetation classes (90% and 83%, respectively). Historical, published land-use maps overestimate wetland surface cover by factors of 2–10 in the study areas. The proposed methods improve speed and efficiency of wetland map production, allow semi-annual monitoring through repeat satellite passes, and improve the accuracy and precision with which wetlands are identified.
While wind and solar have been the leading sources of renewable energy up to now, waves are increasingly being recognized as a viable source of power for coastal regions. This study analyzes integrating wave energy into the grid, in conjunction with wind and solar. The Pacific Northwest in the United States has a favorable mix of all three sources. Load and wind power series are obtained from government databases. Solar power is calculated from 12 sites over five states. Wave energy is calculated using buoy data, simulations of the ECMWF model, and power matrices for three types of wave energy converters. At the short horizons required for planning, the properties of the load and renewable energy are dissimilar. The load exhibits cycles at 24 h and seven days, seasonality and long-term trending. Solar power is dominated by the diurnal cycle and by seasonality, but also exhibits nonlinear variability due to cloud cover, atmospheric turbidity and precipitation. Wind power is dominated by large ramp events–irregular transitions between states of high and low power. Wave energy exhibits seasonal cycles and is generally smoother, although there are still some large transitions, particularly during winter months. Forecasting experiments are run over horizons of 1–4 h for the load and all three types of renewable energy. Waves are found to be more predictable than wind and solar. The forecast error at 1 h for the simulated wave farms is in the range of 5–7 percent, while the forecast errors for solar and wind are 17 and 22 percent. Geographic dispersal increases forecast accuracy. At the 1 h horizon, the forecast error for large-scale wave farms is 39–49 percent lower than at individual buoys. Grid integration costs are quantified by calculating balancing reserves. Waves show the lowest reserve costs, less than half wind and solar.
The Marine Strategy Framework Directive (MSFD) mandates that European Union (EU) member states achieve Good Environmental Status (GEnS) based on an ecosystem-based approach to management. For commercial fisheries, the primary target under the MSFD is one of maximum sustainable yield. Of Black Sea riparian nations, only Romania and Bulgaria are EU member states. Focusing at the supranational level, we review institutions and instruments relevant to management of the Black Sea. The economic values of current fish catches are assessed, and the results of a recent analytical assessment of fish stocks are used to estimate potential future values based on maximum sustainable yields. In the Black Sea region, despite long-standing attempts to improve fisheries management, there remains a lack of effective regional cooperation. Evidence from the scenario analysis suggests that achieving GEnS would not have an undue negative impact on overall fishery sector incomes, and could, with appropriate investments in processing and marketing, deliver increased economic benefits for Black Sea countries. The ongoing policy debate between and within Black Sea coastal states needs to be extended to include recognition of the potential economic and social benefits of effective fisheries management. More work is required to assess returns on investment in interim management measures to deliver GEnS.
The Black Sea has suffered severe environmental degradation. Governance of the Black Sea region is complex and results in a series of scale mismatches which constrain management. This paper develops a simple classification of spatial scale mismatches incorporating the driver, pressure, state, welfare, response (DPSWR) framework. The scale mismatch classification is applied to two major environmental problems of the Black Sea, eutrophication and small pelagic fisheries. A number of scale mismatches are described and classified and potential solutions are identified.
The Mediterranean region is of fundamental importance to Europe given its strategic position. The responsibility for its overall ecosystem integrity is shared by European Union Member States (EU-MS) and other Mediterranean countries. A juxtaposition of overlapping governance instruments occurred recently in the region, with the implementation of both the Marine Strategy Framework Directive (MSFD) for EU-MS and the Ecosystem Approach Strategy (ECAP) for all Mediterranean countries, including EU-MS. Both MSFD and ECAP are structured around vision-driven processes to achieve Good Environmental Status and a Healthy Environment, respectively. These processes have clear ecosystem-based, integrated policy objectives to guarantee the preservation and integrity of Mediterranean marine ecosystem goods and services. However, adoption of these instruments, especially those related to the new EU-MS directives on marine policy, could result in a governance gap in addition to the well-known economic gap between the EU and the non-EU political blocs. We identify two complementary requirements for effective implementation of both MSFD and ECAP that could work together to reduce this gap, to ensure a better alignment between MSFD and ECAP and better planning for stakeholder engagement. These are key issues for the future success of these instruments in a Mediterranean region where discrepancies between societal and ecological objectives may pose a challenge to these processes.
In this paper we focus on systemic delays in the Baltic Sea that cause the problem of eutrophication to persist. These problems are demonstrated in our study by addressing three types of delays: (1) decision delay: the time it takes for an idea or perceived need to be launched as a policy; (2) implementation delay: the time from the launch of a policy to the actual implementation; (3) ecosystem delay: the time difference between the implementation and an actual measurable effects. A policy process is one characterized by delays. It may take years from problem identification to a decision to taking action and several years further for actual implementation. Ecosystem responses to measures illustrate that feedback can keep the ecosystem in a certain state and cause a delay in ecosystem response. These delays can operate on decadal scales. <br /> <br /> Our aim in this paper is to analyze these systemic delays and especially to discuss how the critical delays can be better addressed in marine protection policies by strengthening the adaptive capacity of marine protection. We conclude that the development of monitoring systems and reflexive, participatory analysis of dynamics involved in the implementation are keys to improve understanding of the systemic delays. The improved understanding is necessary for the adaptive management of a persistent environmental problem. In addition to the state of the environment, the monitoring and analysis should be targeted also at the implementation of policies to ensure that the societies are investing in the right measures.
Our ability to meet environmental targets is often constrained by processes and events that occur over long timescales and which may not be considered during the planning process. We illustrate with examples and define three major types of temporal scale phenomena of relevance to marine managers: Memory and Future Effects (jointly called Legacy Effects) and Committed Behaviors. We examine the role of these effects in achieving marine environmental targets in Europe under the Marine Strategy Framework Directive and the implications for future management, indicating the increased importance that these temporal phenomena give to reducing future pressures.
The sustainable exploitation of marine ecosystem services is dependent on achieving and maintaining an adequate ecosystem state to prevent undue deterioration. Within the European Union, the Marine Strategy Framework Directive (MSFD) requires member states to achieve Good Environmental Status (GEnS), specified in terms of 11 descriptors. We analyzed the complexity of social-ecological factors to identify common critical issues that are likely to influence the achievement of GEnS in the Northeast Atlantic (NEA) more broadly, using three case studies. A conceptual model developed using a soft systems approach highlights the complexity of social and ecological phenomena that influence, and are likely to continue to influence, the state of ecosystems in the NEA. The development of the conceptual model raised four issues that complicate the implementation of the MSFD, the majority of which arose in the Pressures and State sections of the model: variability in the system, cumulative effects, ecosystem resilience, and conflicting policy targets. The achievement of GEnS targets for the marine environment requires the recognition and negotiation of trade-offs across a broad policy landscape involving a wide variety of stakeholders in the public and private sectors. Furthermore, potential cumulative effects may introduce uncertainty, particularly in selecting appropriate management measures. There also are endogenous pressures that society cannot control. This uncertainty is even more obvious when variability within the system, e.g., climate change, is accounted for. Also, questions related to the resilience of the affected ecosystem to specific pressures must be raised, despite a lack of current knowledge. Achieving good management and reaching GEnS require multidisciplinary assessments. The soft systems approach provides one mechanism for bringing multidisciplinary information together to look at the problems in a different light.
Marine environments have undergone large-scale changes in recent decades as a result of multiple anthropogenic pressures, such as overfishing, eutrophication, habitat fragmentation, etc., causing often nonlinear ecosystem responses. At the same time, management institutions lack the appropriate measures to address these abrupt transformations. We focus on existing examples from social–ecological systems of European seas that can be used to inform and advise future management. Examples from the Black Sea and the Baltic Sea on long-term ecosystem changes caused by eutrophication and fisheries, as well as changes in management institutions, illustrate nonlinear dynamics in social–ecological systems. Furthermore, we present two major future challenges, i.e., climate change and energy intensification, that could further increase the potential for nonlinear changes in the near future. Practical tools to address these challenges are presented, such as ensuring learning, flexibility, and networking in decision-making processes across sectors and scales. A combination of risk analysis with a scenario-planning approach might help to identify the risks of ecosystem changes early on and may frame societal changes to inform decision-making structures to proactively prevent drastic surprises in European seas.
Choke points are social, cultural, political, institutional, or psychological obstructions of social-ecological systems that constrain progress toward an environmental objective. Using a soft systems methodology, different types of chokes points were identified in the Outer Hebrides of Scotland, the Baltic, and the North and Mediterranean seas. The choke points were of differing types: cultural and political choke points were identified in Barra and the Mediterranean, respectively, whereas the choke points in the North Sea and Baltic Sea were dependent on differing values toward the mitigation of eutrophication. We conclude with suggestions to identify and address choke points.
The European Union Marine Strategy Framework Directive requires the Good Environmental Status of marine environments in Europe's regional seas; yet, maritime activities, including sources of marine degradation, are diversifying and intensifying in an increasingly globalized world. Marine spatial planning is emerging as a tool for rationalizing competing uses of the marine environment while guarding its quality. A directive guiding the development of such plans by European Union member states is currently being formulated. There is an undeniable need for marine spatial planning. However, we argue that considerable care must be taken with marine spatial planning, as the spatial and temporal scales of maritime activities and of Good Environmental Status may be mismatched. We identify four principles for careful and explicit consideration to align the requirements of the two directives and enable marine spatial planning to support the achievement of Good Environmental Status in Europe's regional seas.
This article presents some fresh reflections on participation in environmental decision-making by focussing on the case of newly designated Marine Conservation Zones (MCZs) under the Marine and Coastal Access Act 2009. The article draws on empirical research conducted by the author with South-East fishermen, considering their perceptions of the designation process. Julia Black’s distinction between ‘thin’ and ‘thick’ proceduralisation serves as a theoretical basis to explain fishermen’s perceptions of the process of designation of MCZs but it is then complemented by observations on knowledge construction and representation, following critical social sciences writings on nature conservation. The argument put forward is that the process of designation of MCZs is an example of ‘thin’ proceduralisation and that a move towards ‘thicker’ forms would benefit from acknowledging the existence of multiple knowledges within each participant and from deconstructing the dichotomy between socio-economic and ecological aspects in thinking about conservation.