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The threat of sea-level rise and climate change means that coastal managers are being increasingly asked to make long-term assessments of potential coastal impacts and responses. In the UK, shoreline management planning (for flood and erosion hazards) and spatial planning now takes a 100 year perspective. An integrated framework across a wide range of physical and social issues is required for the assessment of coastal impacts and consequently for making sound management decisions. This paper provides an overview of the development of the ‘Tyndall Coastal Simulator’ including the underlying philosophy that is being followed. The Simulator is based on a series of linked climate models (CM) within a nested framework which recognises three spatial scales: (i) the global (GCM) scale; (ii) the regional scale and (iii) the Simulator Domain (a physiographic unit, such as a coastal sub-cell). Within the nesting, the larger scale provides the boundary conditions for the smaller scale. The models feed into each other and describe a range of relevant processes: sea level, tides, surges, waves, sediment transport and coastal morphology. Different climate scenarios, as well as the range of uncertainty, are being explored. Communication of results is a major issue and the Simulator includes a dedicated GIS-based user interface that allows a wide range of queries of model outputs. The paper demonstrates the possibility of developing an integrated framework that is multi-scale and capable of linking various models in order to simulate complex coastal processes and consequently allowing long-term assessments that are useful for setting future management plans.

This paper provides an overview of the development of the 'Regional Impact Simulator' - a user friendly software tool designed to allow stakeholders to perform integrated assessments of the effects of climate and/or socio-economic change on the important sectors and resources of two contrasting UK regions. This includes the assessment of agriculture, water resources, biodiversity and coastal and river flooding. The tool arose from the need to further develop the methods applied in the earlier RegIS project, which was the first local to regional integrated assessment in the UK. The limitations of RegIS included very long run times, a limited number of simulations, incomplete linkages between models and no allowance for scenario uncertainty. Based upon the stakeholder needs identified within RegIS, a series of guiding principles were developed with Steering Committee stakeholders, which informed the concept of the 'Regional Impact Simulator' including functionality, appearance and complexity. An Integrated Assessment Methodology based upon the Drivers-Pressure-State- Impact-Response (DPSIR) framework facilitated the integration of multiple models, scenarios and datasets within the software interface. The development of the 'Regional Impact Simulator' provides a test-bed for further studies of stakeholder-led, regional, integrated assessment, and provides an opportunity to learn the many lessons in undertaking such studies.

Climate change will have pervasive effects on the world’s coasts, but at broad scales these changes have typically proven difficult to analyse in a quantifiable manner. Consequently, individual management decisions are often taken without consideration of the wider, regional coastal system with its physical linkages between geomorphological elements.

Coastal habitats are being widely degraded and squeezed around the world due to human pressure and competition for space in the coastal zone. Rising sea levels and other aspects of climate change are and will continue to exacerbate these problems. At the same time, the value of these habitats is increasingly recognised through policies such as the EU Habitats Directive and the UK National Ecosystem Assessment, in terms of the ecosystem services they provide. As a result, management goals such as ‘no-net-loss’ targets have been implemented, requiring habitat creation or restoration projects to be included in coastal management plans.

The preceding chapters have laid out the range of challenges of coastal simulation to support future coastal management, with a particular focus on understanding erosion, flood and habitat changes and their links to coastal management. The detailed case study in Norfolk places the theory and generic principles in a real-world management context that is particularly relevant to the UK, while international case studies (Chap. 13) have introduced a range of alternative challenges and perspectives.

Coastal planners and managers face a wide range of challenges around the world during the twenty-first century. These include geomorphological, climatic, and socio-economic drivers of change, their interaction and the societal and governance issues that they raised. The interplay between these challenges motivated the Tyndall Centre for Climate Research’s Coastal Research Programme.

The Tyndall Coastal Simulator comprised a wide range of modelling activities across disciplines and institutions. This activity generated diverse results, described in the preceding chapters. Organising this body of knowledge into a coherent and accessible form for use by stakeholders and for additional ad hoc analyses emerged as a substantial task in its own right.

Coastal hazards have long been present and are evolving due to a variety of different drivers: the long-term threat of climate change, including sea-level rise, adds a new dimension to these problems which is explored here. Globally, sea levels could rise in excess of 1 m this century, but the local rate of relative sea-level rise could be much greater than this because of subsidence or other factors which lower the land surface. This is important as the population of these subsiding areas is significant. Relative sea-level rise will result in inundation, flooding, erosion, wetland loss, saltwater intrusion and impeded drainage. This chapter has investigated the impacts of sea-level rise at a global scale on: (1) Sandy environments; (2) Wetlands and low-lying coasts; (3) Built environments; and (4) Energy and transport systems. Results indicate that without appropriate adaptation, environments could be significantly impacted, and those remote or financially less well off could become increasingly vulnerable. Further research and action is required into integrated impact assessments (including non-climatic drivers of change) to help those at risk and develop appropriate adaptation polices over short, medium and long timescales.

Deltas, occurring at the mouths of river systems that deposit sediments as they enter the sea, are some of the most dynamic sedimentary environments. They contain a long, and often economically significant, sedimentary record of their response to past episodes of climate and sea-level change. Geological investigation of these deposits, and the processes controlling sedimentation, provide insights into the response of deltas to environmental change, which in turn may offer rational and cost-effective strategies for the sustainable management of natural resources and land use in these dynamic systems in the face of future environmental change.

Seabed drag coefficients have been measured at a site within the Norfolk Banks and at a site within the sand wave field in the southern North Sea, using pressure sensors and moored current meters. At the sand banks site a seabed tripod measuring turbulent flows within 1 m of the bed was also used. The results are generally in agreement with values used in numerical models. At the sand banks site, the drag coefficient increases with wind conditions, but at the sand waves site there is a reduction during the highest wave conditions, attributed to the drag reduction caused by sand resuspension from the bed. This result suggests that sediment effects must be considered if wave/current interaction is included in numerical models of the region. The drag coefficient for reversing tidal flows over the asymmetric sand waves is found to be larger for flow towards the steeper face, suggesting a small form drag component.