Assessing the future impact of coastal change
ArcGIS shows us not only where coastal change has occurred in Scotland over the last century, and how quickly, but where future changes will occur and which of our infrastructure assets will be at risk.
Public sector organisations can collaborate more effectively with a shared understanding of coastal change
Businesses can identify risks to their property and make well-informed decisions to protect their assets
Members of the public can better understand and prepare for coastal changes in Scotland
“ If we had been doing this project five years ago, before ArcGIS Online, we wouldn’t have been able to be as responsive to the original vision of the project and share our coastal change insight with everyone ”
Lachlan Renwick – GIS Services Manager, Scottish Natural Heritage
While Scotland is renowned for its spectacular coastal cliffs and scenic rocky coves, 19% of the country’s 21,000 km of shoreline is formed of beaches, sand dunes and saltmarshes. Government and university experts are concerned about the potential long-term implications of climate change on these soft landforms, because they are highly susceptible to erosion, as well as accretion from the build-up of sediments along the coast.
The Scottish Government recognises the importance of the likely future impacts of climate change on Scotland’s soft coastal landscapes and joined forces with Scottish Natural Heritage (SNH) and the University of Glasgow to undertake the country’s first ever National Coastal Change Assessment. However, before researchers could begin to assess future risks, they first needed to understand what changes had taken place in the last 120 years, where they had occurred and the pace at which these changes had happened.
“ Ultimately the information in DynamicCoast.com helps Scotland, its businesses and communities become more resilient to climate change ”
Professor Jim Hansom – Principal Researcher for Dynamic Coast, University of Glasgow
With funding from Scotland’s Centre of Expertise for Waters (CREW), researchers used Esri’s ArcGIS Desktop to analyse geo-rectified historical maps from the 1890s and 1970s alongside modern maps and LiDAR surfaces. They used over a million data points in the soft, erodible sections of the Scottish shoreline and built up a fully interactive map, enabling them to not only depict a century of coastal change, but also calculate the rate of change for every 10 metres of the soft coast. The analysis showed an increase in erosion extent of 39%, a fall in extent of accretion of 22% and a doubling of erosion rates, above historic baseline levels.
Using this evidence base, the researchers then performed sophisticated spatial analysis to identify areas likely to experience future change. They highlighted the areas of anticipated future erosion in dark red on the map and included a ten metre erosion influence area, which together includes more than 50 buildings, 5 km of roads, 2 km of railway and 2 km of water pipes that may be threatened by erosion by 2050. Over £340m of assets are at risk if erosion continues, however, in total, £13bn of assets are protected by ‘natural defences’.
Finally, the project team used Esri’s ArcGIS Online platform to share its insight into coastal erosion via an accessible web map that everyone can easily view, interrogate and understand. Called DynamicCoast.com, it enables people to browse every beach in Scotland, zoom in to view potential erosion risks at any location, using any device, whether they are at home, at work or standing on a beach. Lachlan Renwick, GIS Services Manager at Scottish Natural Heritage says, “If we had been doing this project five years ago, before ArcGIS Online, we wouldn’t have been able to be as responsive to the original vision of the project and share our coastal change insight with everyone.”
“ The GIS-led research approach we developed gives us accurate, statistical evidence and allows us to provide objective recommendations with confidence ”
Dr Alistair Rennie – Dynamic Coast Project Manager, Scottish Government
Firm evidence of climate change along Scotland’s coast
Using ArcGIS Desktop, researchers have gained tangible evidence about climate change, which they can use to make secure judgements about the future. “As scientists, we are all inherently cautious about making future predictions, yet as advisors we need to give advice to help the Scottish Government, businesses and citizens prepare for the future,” says Dr Alistair Rennie, Dynamic Coast Project Manager, Scottish Government. “The GIS-led research approach we developed gives us accurate, statistical evidence and allows us to provide objective recommendations with confidence.”
Improved resilience to climate change
By accessing DynamicCoast.com, the public and organisations can now easily find out how the continuance of past coastal changes may impact their property and assets and, as a result, make better informed decisions to reduce their longer term risks and costs. For instance, electricity suppliers can use the information to plan the installation of new electricity cables with more confidence, to avoid those areas where their condition and safety may be jeopardised by erosion or changing sea levels in the future. The University of Glasgow’s Prof. Jim Hansom, Principal Researcher for Dynamic Coast, says: “Ultimately the information in DynamicCoast.com helps Scotland, its businesses and communities become more resilient to climate change.”
Greater public awareness of coastal change
As the data is displayed on simple-to-use, interactive maps via ArcGIS Online, people with absolutely no prior experience of GIS can easily understand the implications of continued erosion and climate change on the areas of coastline where they live, work or visit. “For many climate change is a vague and distant topic, but everyone can now see for the first time, precisely how much change has happened and what the future impacts may be on the specific beaches they love,” Renwick says.
A collaborative response to the challenges of coastal change
The versatility of the ArcGIS platform, and the breadth of the analysis available, is the cornerstone of future collaboration between government bodies in Scotland and will lead to more joined-up responses to the challenges of coastal change. Organisations like SNH, SEPA, Historic Environment Scotland and Local Authorities can work more effectively together to assess the implications for threatened sites of historical and environmental interest and put strategies in place to protect and preserve them for future generations.