Coastal Experts Research Articles

Numeričko modeliranje hidrodinamičke izvedbe na poroznom kosom tipu plutajućeg lukobrana

A breakwater is a coastal building that aims to break up or withstand wave energy that enters the beach so that the characteristics of the incoming waves are by calculations and can reduce abrasion on the shoreline. Designing a floating breakwater is very complicated because it depends on many aspects. These fundamental aspects depend on each other, so if one of these aspects changes, the integrity of the floating breakwater structure will also change. One of these aspects is the magnitude of the transmission and reflection coefficients generated by the floating breakwater. This research will study the hydrodynamic performance of floating breakwater due to variations in slope and porosity in reducing and reflecting waves with computational fluid dynamics (CFD). The slope-porous floating breakwater dimension is based on previous experimental data, including a constant water depth of 0.75 m, a wave height of 0.05 - 0.125 m, and a wave period of 1.1 - 2 sec on regular waves. The results of the numerical model validation and experiments on all variations of the floating breakwater model are quite good, which is less than 10% for both wave transmission and reflection. Analysis of the influence of changes in the mooring line angle, the simulation is carried out at an angle of 30 deg to 90 deg and produces an average transmission coefficient of 0.79 and a reflection of 0.21. While the effect of changes in water level elevation (0.85 m, 0.75 m, and 0.65 m) gives a reasonably significant average transmission coefficient of 0.85 and a reflection of 0.13. The mooring line angle will be gentler at high tide, and the transmission and reflection coefficients will be higher. However, the mooring line will loosen at low tide, causing the structure to move more freely and eliminating the function of the floating breakwater itself so that the tidal phenomenon becomes a challenge for coastal experts in designing structures to produce effective and efficient hydrodynamic performance.

Informing the Development of the Coast Model of the Watershed Game

AbstractSince 2006 the Watershed Game, a role‐playing simulation and serious game focused on managing nonpoint source pollution at the watershed scale, has been used across the U.S. to improve understanding of, commitment to, and involvement in watershed‐scale management. Stakeholder or student participants manage a fictitious watershed to meet a “Clean Water Goal.” Designed for freshwater watersheds, the game is available in local leader and classroom versions, and play is led by trained facilitators or educators. To inform the expansion of the Watershed Game to include coastal watersheds, a needs assessment was conducted to identify water quality and management challenges in coastal regions, using the Gulf of Mexico and South Atlantic as a case study. Several methods for assessing critical coastal management challenges and key land uses to prioritize in the game were employed: a review of reports, expert focus group, survey of Gulf and South Atlantic regional experts, second survey of coastal experts from the National Sea Grant Network to verify widespread applicability, and finally pilot tests of the draft game. Results showed high agreement among assessment methodologies regarding the most critical coastal challenges and important land uses to feature in the game. As a result, the Coast Model of the Watershed Game focuses on three primary nonpoint source pollutants, excess nitrogen, excess phosphorus, and excess sediment. Additionally, results indicated a need to integrate a new game element, resilience to flooding, which has been added to the challenge of winning the game by meeting the Clean Water Goal.

Challenges and opportunities for sustaining coastal wetlands and oyster reefs in the southeastern United States

Formed at the confluence of marine and fresh waters, estuaries experience both the seaside pressures of rising sea levels and increasing storm severity, and watershed and precipitation changes that are shifting the quality and quantity of freshwater and sediments delivered from upstream sources. Boating, shoreline hardening, harvesting pressure, and other signatures of human activity are also increasing as populations swell in coastal regions. Given this shifting landscape of pressures, the factors most threatening to estuary health and stability are often uncertain. To identify the greatest contemporary threats to coastal wetlands and oyster reefs across the southeastern United States (Mississippi to North Carolina), we summarized recent population growth and land-cover change and surveyed estuarine management and science experts. From 1996 to 2019, human population growth in the region varied from a 17% decrease to a 171% increase (mean = +43%) with only 5 of the 72 SE US counties losing population, and nearly half growing by more than 40%. Individual counties experienced between 999 and 19,253 km2 of new development (mean: 5725 km2), with 1–5% (mean: 2.6%) of undeveloped lands undergoing development over this period across the region. Correspondingly, our survey of 169 coastal experts highlighted development, shoreline hardening, and upstream modifications to freshwater flow as the most important local threats facing coastal wetlands. Similarly, experts identified development, upstream modifications to freshwater flow, and overharvesting as the most important local threats to oyster reefs. With regards to global threats, experts categorized sea level rise as the most pressing to wetlands, and acidification and precipitation changes as the most pressing to oyster reefs. Survey respondents further identified that more research, driven by collaboration among scientists, engineers, industry professionals, and managers, is needed to assess how precipitation changes, shoreline hardening, and sea level rise are affecting coastal ecosystem stability and function. Due to the profound role of humans in shaping estuarine health, this work highlights that engaging property owners, recreators, and municipalities to implement strategies to improve estuarine health will be vital for sustaining coastal systems in the face of global change.

Methodologies to support coastal management - A stakeholder preference and planning tool and its application

Stakeholder involvement plays a crucial role within Integrated Coastal Management (ICM) and is considered beneficial for gaining trust and knowledge and reducing conflicts. Nevertheless, disagreement and opposition among stakeholders and lack of manager experiences in participatory approaches have caused delays in ICM processes. A major challenge is to systematically guide target oriented discussions of heterogenic groups in order to reach consensus decisions based on sustainability objectives. Hence, this research aims to provide a stakeholder preference and planning tool that can be used to support participatory processes. For this, the DeCyDe-4-Sustainability methodology was tested and built upon. Seventeen applications with coastal experts, graduate students and stakeholders of ICM initiatives were carried out, which showed how the methodology can be adjusted and used for guiding stakeholder discussions systematically and generating a common understanding, for raising awareness about sustainability and evaluating concrete measures using success criteria. With a sound preparation, adaptation to local needs and combination with an indicator-based evaluation, the methodology can be applied to guide stakeholder involvement processes within ICM. The System Approach Framework (SAF) with its stepwise approach from the issue identification to the implementation of a solution and evaluation of success was found to serve as a suitable frame. Hereby, the modified stakeholder preference and planning tool can guide discussions from generating a general view of an area and problems therein, down to the selection and evaluation of concrete measures to tackle the problem and its effects on a larger level and contribution to a sustainable coastal development.

How close to the coast? Incorporating coastal expertise into decision-making on residential development in Australia

The most recent assessment of the Intergovernmental Panel on Climate Change confirms the importance of adaptation strategies such as ‘retreat, accommodate or protect’ but emphasizes the significance of institutional and governance structures in decision-making. Even without the threat of climate change there is a legacy of vulnerable coastal development in many parts of the world where there has been a lack of understanding of coastal processes. Coastal vulnerability and adaptation strategies are well covered in the literature but the extent to which coastal experts are used to advise on development in vulnerable coastal areas has to date received scant attention.Expert coastal advice is essential to reduce vulnerability of coastal residential development to both existing coastal erosion and flooding and in particular to the threat of increased vulnerability associated with future climate change. This paper uses the Australian system of coastal management, where responsibilities rest mostly with state governments, to discuss the nature of coastal experts and the types of advice they provide. We focus specifically on the relevant legislation, statutory coastal authorities, coastal strategies, coastal planning and decision-making, where there are clear pathways for incorporating expert coastal advice. Only four states have dedicated coastal legislation and each state has its own planning legislation, which is linked to one or more pieces of legislation covering coastal development. Two case studies are used from different states to illustrate how these mechanisms for incorporating expert advice operate in practice. Our analysis includes both anecdotal case studies plus a more detailed quantitative analysis from one state using a decade of records to illustrate temporal patterns in the use of expert advice.The paper concludes that Australia has a variable use of adopting coastal expert advice into the coastal residential development approval process because each state has different stages where the advice is incorporated into its planning system. These variations can be represented along a continuum of specificity for expert advice provided. It appears that none of the states provides a fail-safe mechanism to prevent residential development being built too close to the coast as shown by case studies described. In one state there is a statutory requirement for referral to an expert coastal body but a proportion of the advice is ignored. Most state jurisdictions are now attempting to mainstream expert advice into planning legislation, policies and guidelines so that best practice principles are adopted early in the development approval process in order to avoid building too close to the coast.

A Social Values Typology for Comprehensive Assessment of Coastal Zone Ecosystem Services

Coastal areas provide a wealth of resources and represent the most developed spaces worldwide. As pressures on these resources increase, managers and policymakers require understanding that facilitates comprehensive valuation of ecosystem services, including social–ecological dynamics and the coupling of social and natural systems. Adoption of ecosystem management approaches has created a need for increased knowledge of social systems commensurate to baseline ecological understanding; that is, managers benefit from integrating stakeholder values into decision-making processes. This study, using the Delphi technique, elicited knowledge and opinions from international coastal experts regarding relevant social values of ecosystem services, facilitating integration of multiple perspectives into an informed consensus typology of 16 social values. Agencies across the board see inclusive evaluation of ecosystem services, including social values, as critical to robust decision making regarding relevant resources. The next step for research findings is application of the typology in resource assessment initiatives within research and practice-based efforts.

The Coastal Hazard Wheel system for coastal multi-hazard assessment & management in a changing climate

This paper presents the complete Coastal Hazard Wheel (CHW) system, developed for multi-hazard-assessment and multi-hazard-management of coastal areas worldwide under a changing climate. The system is designed as a low-tech tool that can be used in areas with limited data availability and institutional capacity and is therefore especially suited for applications in developing countries. The CHW constitutes a key for determining the characteristics of a particular coastline, its hazard profile and possible management options, and the system can be used for local, regional and national hazard screening and management. The system is developed to assess the main coastal hazards in a single process and covers the hazards of ecosystem disruption, gradual inundation, salt water intrusion, erosion and flooding. The system was initially presented in 2012 and based on a range of test-applications and feedback from coastal experts, the system has been further refined and developed into a complete hazard management tool. This paper therefore covers the coastal classification system used by the CHW, a standardized assessment procedure for implementation of multi-hazard-assessments, technical guidance on hazard management options and project cost examples. The paper thereby aims at providing an introduction to the use of the CHW system for assessing and managing coastal hazards.

Change in the way we live and plan the coast: stakeholders discussions on future scenarios and adaptation strategies

Schmidt, L., Delicado, A., Gomes, C., Granjo P., Guerreiro, S., Horta, A., Mourato, J., Prista, P., Saraiva, T., Truninger, M., O’Riordan, T., Santos, F.D., and Penha-Lopes, G. 2013. Change in the way we live and plan the coast: stakeholders discussions on future scenarios and adaptation strategies In: Conley, D.C., Masselink, G., Russell, P.E. and O’Hare, T.J. (eds.), Proceedings 12 th International Coastal Symposium (Plymouth, England), Journal of Coastal Research, Special Issue No. 65, pp. 1033-1038, ISSN 0749-0208. A scenario of increased risks due to climate change and coastal erosion, coupled with a stringent economic recession, is threatening the Portuguese coast. Three particular locations are the focus of CHANGE – Changing Coasts, Changing Climate, Changing Communities, a 3-year study (2010-2013) that aims to understand social perceptions about coastal risks and to examine new ways of adaptive management. The project involved assessing peoples’ representations about the coastal present and possible coastal futures and discussed coastal change with local populations, in a country in which the protection of vulnerable coast to date has had little public involvement. The three coastal stretches studied face increasing coastal risks and the perspective of reduced public spending, fuelling uncertainty about their future. Public participation in coastal management has been almost entirely absent, which makes the social science based contribution of this research even more relevant. This research combines: a) scientific assessments on the past and future evolution of the shoreline, taking into account the impacts of climate change; b) interviews with policy-makers, coastal experts and stakeholders, as well as local public opinion surveys; c) the outputs of a model for coastal governance and community building, based on local discussions through focus groups and workshops. This paper is based on the surveys and focus groups undertaken in the case-study area most at risk from coastal change, Vagueira. We conclude that there is a growing perception of coastal threat and potential for the development of adaptive coastal management, taking advantage of local knowledge and initiative.

Experts' evaluation of concepts of Ecologically Sustainable Development applied to coastal ecosystems

With the broad aim of promoting the essential interdisciplinary research on sustainable development and contributing to the development of an operational bio-economic analysis, the present paper attempts to evaluate four representative approaches to Ecologically Sustainable Development (ESD) in the context of coastal ecosystems. These approaches are non-declining utility per capita, preservation of all the existing natural capital, preservation of the biological crucial levels, and conservation of the critical natural capital. They reflect contemporary dialogue and especially the tension between the schools of strong and weak sustainability. The evaluation was performed by the international community of coastal experts through responses to a questionnaire survey (n = 99).It emerges that those approaches to ESD that integrate operational criteria and principles from natural sciences within the consideration of socioeconomic welfare are evaluated as more functional as well as scientifically more appropriate for defining the target of ESD in coastal ecosystems.

The vanishing coast

In the wake of Hurricane Katrina, coastal experts are trying to gauge the destruction to Louisiana's marshes. Emma Marris travels to the coast to learn what might be saved — and what might not.

PRINCIPLES OF SHORE PROTECTION FOR THE GREAT LAKES

The Great Lakes region is one of quiet challenge and absorbing interest to the coastal engineer. From the broad pattern of its morphologic history to the detail of its present-day shoreline it presents a fascinating variety of natural phenomena and man-imposed regimen that has controlled and still conditions its shoreline behavior. Many of the features of the behavior pattern and its controls are recognized and subject to beneficial management) some of these are either not recognized or are ignored by coastal experts who should know better; while others are as yet beyond the capabilities of the methods of beneficial management available today.