We all enjoy a day out at the coast. Ice cream, beaches, waves, and perhaps a cliff top walk can all make for the perfect getaway. Coastal zones also attract human settlement, business and industry, and are instrumental to the functioning of societies both in coastal states and the wider global community. However, our oceans and coasts are under growing pressure as human practices change, populations rise and the impact on climate change increases.
These man-made impacts are far-reaching and are already changing the lives and livelihoods of coastal communities. Many of us have probably seen footage of houses falling off cliffs and into the sea on news stories. But these behaviours can also further threaten valuable ecosystems and damage industries, such as tourism, fishing and shipping.
The future for our coasts is complex. Decision-making and environmental management in coastal areas requires the ability to understand and quantify the variability of change and deformation of beaches and cliffs over time, but how can we do this?
In ecology, ‘resilience’ is a term used to mean the ability of an ecosystem to withstand change or bounce back after a shock. We can also use the term in a societal or socio-ecological sense to mean the ability of a particular population and its environment to undergo change or shocks without collapsing into an undesired state. In terms of managing our coastlines, these could be relatively slow changes, such as a rise in sea level, or a sudden shock, such as flooding.
The concept of resilience is useful for developing adaptation measures and guarding against the uncertainties of changes in human practice, rising populations and the impact of climate change. It can inform urban planning to reduce flood damage or help develop an early warning system.
However, embracing the concept of resilience in managing our coastlines marks a step change in thinking.
Mapping the future
Today, rapidly advancing surveying technologies, capable of generating high resolution bathymetric and topographic data, allow precise measurements of geomorphological change and deformation in coastal regions, permitting great accuracy in the characterisation of volumetric change, sediment and debris flows, accumulations and erosion rates. In addition, emergent proximal and remote sensing technologies are able to generate far higher spatio-temporal resolution measurements for coastal areas than have been previously available, in both the vertical and horizontal planes. These methods can allow more precise measurements of coastal retreat to be undertaken than those extrapolated from traditional topographic maps or aerial photos.
However, such data is underutilised by coastal practitioners in their assessments of coastal change, due to a lack of awareness of the appropriate analytical techniques and the potential benefits offered by data-driven approaches.
A data-driven approach
High quality data-driven approaches are an excellent basis of rational decision-making. There are large volumes of ‘triple bottom line’ data, representing a wide variety of environmental, social, and economic themes in coastal regions. This data is especially crucial in the development of environmental risk evaluations for our coast as it can reduce subjectivity and facilitate a more sustainable, evidence-based management of our coastal regions.
The Natural Environment Research Council (NERC) funded programme ‘Constructing a Digital Environment’ recently showcased key digital tools for coastal management at the American Association for the Advancement of Sciences (AAAS) event, held in Seattle, USA. In this event, digital tools were applied to two contrasting coastlines:
- The low-lying Mississippi Delta, which is undergoing significant coastal erosion from submersion and storm events
- The English coast of East Anglia, which is undergoing erosion through material from the coast by wave action, tidal currents and groundwater seepage.
In practical terms, the use of digital tools helps analyse and visualise the amount of lost coastline, identify areas at risk and - through the development of a digital twin of the coastline - determine the best mitigation and resilience strategies which can inform Shoreline Management Plans (SMPs).
Shoreline management plans
SMPs provide a large-scale assessment of the risks associated with coastal processes, and seek to reduce these risks to people and the developed, historic and natural environments.
Each SMP will look at the natural forces shaping the shoreline to assess how they are likely to change over the next 100 years, taking account of the condition of existing defences. It will then develop policies that outline how the shoreline should be managed in the future, balancing the scale of the risks with the social, environmental and financial costs involved, and avoiding adverse impacts on adjacent coastal areas.
Together with the digital twin these approaches help us manage our coastlines for resilience. They support responses to acute events and inform our understanding of long-term environmental change, by bringing together environmental research and environment-focused informatics (such as statistics, machine learning and computer science) and social science to improve the understanding, modelling and prediction of events and inform future decision-making.