Improving our ability to predict how coastlines will change is an essential part of quantifying risks from coastal erosion and flooding. Coastal Modelling Environment, or CoastalME, is a free tool created by BGS in partnership with the Environmental Change Institute (ECI) at the University of Oxford and the University of Southampton.

CoastalME is being used in the UK and internationally to provide improved predictive capability for coastal adaptation. Modellers can use CoastalME to simulate the interaction of coastal landforms and human interventions for open coast systems. This enables users to model and visualise coastal landscape changes more effectively using commonly available spatial data.

The operational tool is being used to inform decision making at regional, international and global levels and was named as a as part of the Government Flood and Coastal Erosion Risk Management research and development programme. At the regional level, the tool is being used as part of the Resilient Coast (RC) project, funded by the Government’s .

The RC project explores the concept of a sediment circular economy for coastal adaptation in East Anglia, in which the release and transit of sediment is mapped and value is assigned where benefits accrue. CoastalME is used to quantify the movement of sand, gravel and fine material along the coast and to determine its value as a nature-based resource. Early results suggest that allowing a 1m landward recession of less than 10m of the cliffs between Felixstowe and Caister would release around 1.8millionm³ of sand.

At an international level, CoastalME has been used in Spain to assess the risk of flooding and erosion for the whole of Andalusia coastline, which extends for 1200 km, measured at a scale of 1:25 000, and traverses five of eight provinces. This study represents the first attempt to map the spatial distribution of sediment thickness along this coastal zone by integrating various publicly available datasets. It demonstrated the flexible design of CoastalME by incorporating representations of geomorphological features such as ‘ramblas’ (a dry riverbed used as a road or thoroughfare) that are important sources of sediment during heavy rainfall events.

After years of developing CoastalME, we are pleased to see that it now been officially released and is freely available to support coastal engineers and decision makers to better assess the risk of compound flooding and erosion more accurately than ever before.

Dr Andres Payo Garcia, head of BGS Coasts and Estuaries.

Funding

This research was initially funded by the NERC iCOAST project as a proof of concept, NE/J005584/1 (2012 to 2016).

The workflow to create the sediment thickness model was developed between 2016 and 2022 thanks to funding from BLUEcoast, NE/N015649/1.

It is being operationalised (2022 to 2027) as part of the ongoing CHAMFER project NE/W004992/1 and is being extended to gravel-dominated coastal environments as part of the 2024 to 2028 UKGravelBarriers project, NE/Y503265/1.

Contact

For more information, please contact 51ÁÔÆæ press (bgspress@bgs.ac.uk) or call 07790 607 010.

The (FCERM) research and development programme areas of interest launched at the beginning of May 2024. Following this, we are highlighting the BGS datasets that can support coastal researchers and practitioners facing adaptation challenges at the coast.

As a result of the complex interaction of natural properties and processes, a range of geohazards converge at the coast and make it a hotspot for financial and societal costs. One such example of these issues is demonstrated by the plight of Fairbourne, a village in west Wales that is . The third UK Climate Change Risk Assessment (CCRA3) has highlighted that all four UK nations are  and the UK lacks national ‘projections of risk to the viability of coastal communities, either from erosion or catastrophic flooding’.

Existing methodologies for assessing national coastal erosion vulnerability often fail to consider how the localised properties and structures of geological deposits can affect coastal change when combined with coastal processes. For example, the (NCERM) for England and Wales states, ‘Details of geologically complex areas known as “complex cliffs” are, in general, not included within the dataset due to the inherent uncertainties associated with predicting the timing and extent of erosion at these locations.’

51ÁÔÆæ GeoCoast

51ÁÔÆæ GeoCoast aims to plug this data gap by providing a suite of nationally consistent geological properties data that can be used by stakeholders as key components within a coastal modelling environment.

51ÁÔÆæ launched GeoCoast in 2022. It is an integrated geographical information system (GIS) package of datasets designed to inform and support coastal management, planning and adaptation around Great Britain. GeoCoast is based on the outputs of numerous research programmes, stakeholder advice and data analytics and provides sufficient data for users to analyse and assess a range of coastal risks.

GeoCoast Premium

GeoCoast Premium is a licenced package that identifies coastal properties at a 50 m scale and consists of three layers:

• erosion susceptibility
• coastal properties
• groundwater flooding zones

Erosion susceptibility

The first layer provides an erosion susceptibility assessment of the coastal stratigraphy. Our regional geology experts considered the 3D geological ‘stack’ of rock types on the coasts of Great Britain, providing unique insight that is not always available from 2D geology maps.

Each rock type in the stack is scored based on a series of geological properties:

• type of discontinuities
• material strength
• permeability

A total score is calculated per rock type and a worst and mean erosion susceptibility score provided for the entire stack. Scores are also classified from ‘low’ to ‘high’, with special consideration given to the rock type at the bottom of the stack as this is most likely to interact with wave action and tidal processes.

Additional information is provided on:

• cliff profile
• complexity of the geological structure of the stack
• whether there have been any previous landslides mapped at this location

This is repeated every 50 m around the high-water line of mainland Great Britain. Projected rates of erosion calculated by the NCERM project are also provided for England and Wales.

Coastal properties grid

The coastal properties grid provides information on a wider coastal range, covering the foreshore and backshore region. Using the data to consider Fairbourne as an example, the grid provides a condensed version of the erosion susceptibility assessment.

Projected coastal inundation extents consider sea level projections from UK Climate Projection (UKCP) 18 under the RCP 4.5 emissions scenario. These projections offer a worst case, undefended view of coastal inundation and therefore do not account for any engineered defences.

The susceptibility of the underlying geology and observed ground motion data have been used to calculate subsidence rates for the entire foreshore and backshore area. It is also available as a potential percentage volume reduction.

The coastal zone has been classified by coastal type.

Groundwater flooding zones

The third component of GeoCoast Premium is the groundwater flooding zone. This layer allows for coastal inundation and groundwater flooding to be considered in tandem as groundwater flooding can exacerbate and prolong coastal flood events and have a particular impact on buried assets such as utilities and foundations. In this layer, a current view of coastal inundation susceptibility is considered rather than a projected view.  

This data highlights some 133 km² of coastline classed as ‘high susceptibility to erosion’ with a further 195 km² in the ‘moderate to high susceptibility’ class. Even if defences are maintained, this is a staggering amount of coastline under threat and there are some 30 000 properties within 25 m of potentially highly susceptible coast. Counties such as Lincolnshire, Hampshire, Norfolk and Lancashire are particularly affected.

GeoCoast Open

GeoCoast Open data is freely available on the and for download. This package provides a range of historic images and diagrams extracted from our archives, memoirs and other publications that can provide a reference for coastal change. It also contains a detailed suite of statistical data based on the GeoCoast Premium datasets. These include, for example, percentage of a shoreline management plan area or local authority coastline at threat from inundation and percentage of coastline with high susceptibility to erosion. In addition, there is a tool to compare or share best practice at a regional scale and streamline the consideration of multiple underlying datasets through a simple, high-level scheme, presented as domains.

A series of are available for seven coastlines of natural importance demonstrating the attribution and application of the datasets. For more information, please visit the 51ÁÔÆæ GeoCoast web pages or do not hesitate to get in touch (digitaldata@bgs.ac.uk).

Gravel-dominated beach and barrier systems are common around the UK and provide important coastal defences, especially in low-lying regions. A new, four-year research project, funded by the Natural Environment Research Council (NERC) and entitled ‘Gravel barrier coasts’ (GBCoasts), will deliver enhanced understanding and modelling of gravel barrier systems. The project aims to support more sustainable coastal management by increasing resilience and reducing the vulnerability of coasts to climate change.

51ÁÔÆæ will use a new community modelling system, ‘Coastal modelling environment (CoastalME)’, alongside terrestrial, marine and groundwater models, to characterise how a combination of processes along gravel barrier coasts control coastal flooding and erosion.

CoastalME will produce numerical simulations to support multi-hazard analyses under present and future climate change scenarios. These will project, over a range of timescales:

• how multi-hazards will respond to predicted climate change processes and impacts
• how humans are affecting future hazards
• how we will be affected under different coastal management scenarios; for example, how do gravel barriers respond to individual events, such as storms, in the context of longer-term, ‘progressive’ trends, such as sea-level rise?

The results will support improved coastal management decision making based on the improved understanding of how gravel barriers evolve over longer time scales under different climate condition and human intervention scenarios.

The findings will be combined with an assessment of the role of coastal habitats, resulting in national maps of vulnerabilities of coastal habitats to climate-driven multi-hazards for protective services. BGS will also provide tools to analyse the efficacy of future coastal management schemes.

The GBCoasts project will enable us to better address the transformational challenges that many communities along the UK coastlines are facing today and in the near future, regarding ever-increasing risks of coastal flooding and coastal erosion.

Andres Payo Garcia, BGS Coastal Geomorphologist.

In order to achieve the objectives of GBCoasts, there will be a collaboration between the different sectors of UK academics, engineering consultants and research institutions.

The hydrological modelling project is a partnership between BGS and governmental and academic institutions in the Philippines. It aims to improve the understanding of national water resources and identify the impact of future climate change and development on these resources.

After flying through multiple time zones and with far less than the recommended eight hours of sleep, we arrived bleary-eyed at Manila airport in the Philippines to meet our hosts from Ateneo de Manila University (ADMU). Our destination for the next few days was Boracay, billed as one of the most popular tourist hotspots in the Philippines. Thoughts of beaches, hammocks and mango ice cream filled our minds as we landed at Caticlan airport and were met by a live band at arrivals.  

New Nabaoy river gauging station

We grabbed our suitcases and headed to our first stop, the Nabaoy river catchment Panay, to view a new river gauging station installed by ADMU and partners at the National Water Resources Board (NWRB). River gauging stations look at the flow and depth of the river, as well as some pollutants. There was a lot to discuss around groundwater residence times (the time water stays in the ground) and further development of sensors. With a light drizzle reminiscent of the UK we headed back into the bus to catch a boat to Boracay and, with the light fading, we made it to the hotel. The beaches would have to wait for tomorrow. 

Rising early, the skies were blue and the breeze was warm and gentle. We met the ADMU and NWRB teams at breakfast to discuss the day work. Two hours later, we were back at the Nabaoy river, talking to the local mayor and various government departments about hydrogeology, modelling and climate before taking part in a ribbon-cutting ceremony. The river gauging station was officially open!

We spent the remainder of the afternoon with the mayor and ran a series of groundwater experiments with local children, teaching them about water resources, pollution and hydrogeology. Once again, those world-famous beaches would have to wait… 

Learning about Boracay

Wednesday began in a similar way to Tuesday, with a large breakfast and a discussion about the plan for the day. We boarded a bus and headed south, passing through the corridor of shops, cafes, homes and hotels that line Boracay western coastline. Again, we were greeted by local and regional government officials for a second ribbon-cutting ceremony at a new groundwater observation well. This time, Andy M was asked to wield the scissors.

An hour later, we were back at the hotel for a conference about the sustainability of water resources on the island. We learnt about the hydrology and ecology of Boracay and the Nabaoy watersheds, including some endemic, foot-long stick insects, and Andy B presented forecasts on the future of regional climate and hydrology up to the end of the century. This generated discussion around potential impacts on water resources and disaster recovery.  

The next day we said our farewells to our project partners and headed to the beach for mango ice cream and to reflect on the last few days. The white sands and turquoise waters were the perfect way to unwind before ten days of delivering workshops, school sessions and training in Manila!

Vulnerability of small islands

The Intergovernmental Panel on Climate Change (IPCC) has identified small islands as high-risk settings facing adverse climate change impacts. They have limited, vulnerable resources and few freshwater sources. Small islands also have a high dependency on tourism in terms of exports and contribution to gross domestic product (GDP), however, tourism needs to be well managed to avoid deterioration of local water supplies.

Small islands present three key characteristics that make them particularly vulnerable to social, economic and environmental impacts:

• small size, which adds pressure on water resources and limits economic diversity
• isolation, which brings trading challenges, unique biodiversity and cultural richness
• maritime environment, leading to vulnerability to climate change

Understanding how climate change and differing tourism approaches impact hydrology provides a pathway to improved water security. Understanding and assessing impacts will require a unique approach integrating geosciences, social science and economics.

Funding

This fieldwork was undertaken as part of the International Geoscience Research and Development (IGRD) project ‘Geoscience to tackle global environmental challenges’. This is a £12 million project lasting until 2026, looking at challenges facing communities around the globe, including clean water availability, earth hazards and climate change impacts.

About the authors

On 25 February 2023, was closed off to the public due to significant coastal erosion. Over the following days, homes and properties on the cliff were evacuated, with some collapsing into the sea because of this loss of land.

The coastal frontage at Hemsby comprises a narrow zone of vegetated sand dunes of very loosely consolidated sand, situated behind a narrow beach. Its weak geology makes the coastline susceptible to this erosion.

Beaches are great natural coastal defences because they act to dissipate wave energy, but at Hemsby, because the beach is so narrow, the erosional susceptibility of the geology is enhanced because of direct wave action on the cliffs. This occurs under both normal tidal and weather conditions and especially during high tides and storms. There is unfortunately a long history of coastal erosion at Hemsby, documented in a wide range of historical (and more modern) accounts.

Jonathan Lee, BGS Regional Geologist.

51ÁÔÆæ research at Hemsby

The BGS Coasts and Estuaries team has been studying the Hemsby coastline by looking at historic and current coastal change as part of the ‘Coastal monitoring and historical coastal change’ project. The team reviewed historical evidence, which suggested that the annual cliff recession rate of UK coastlines can vary from almost nothing, if the beach is wide and thick enough, up to as much as 25 m in a single year if the beach is narrow and thin. We are working to understand whether we will see more of these events in the future under different climates and management interventions.

Property owners along non-defended coast in north Norfolk should be aware of the direct relationship between a beach wedge (combined beach width and thickness) and the level of protection. Once the beach wedge is below 10 m² per metre of beach length, the protection offered by the beach is negligible and the cliff retreat is controlled by the combination of high tides and moderate energy waves (also known as multi-hazards).

Other risks around the coast

Hemsby is not the only erosion hotspot that needs a transformational change in England. The scale of shift at the coast is significant and requires long-term strategic planning involving collaboration across all scales, levels and sectors of government, academics, consultants and communities.

A recent paper by the coasts and estuaries team explores the scale of the and how flood risks may change around England’s coast. The paper confronts the importance of accepting the challenge we as a country face regarding coastlines and calls attention to the need to have honest debates around how we respond fairly and sustainably to coastal erosion in the longer term. We must realise that it will not be possible to protect every property and the clearer we are on a long-term strategy, the more clarity and support can be provided for communities that may be affected.

The paper highlights:

It is important to note that we are not suggesting the 150 000 to 200 000 properties at increased risk to coastal erosion under climate change scenarios will be lost. Many will continue to be protected, but we are highlighting the importance of accepting the scale of challenge and setting out a long-term plan. This challenge was also recognised in the , James Bevan.

Dissemination event

The final output of the project will be presented at the BGS headquarters in Nottingham on 30 March 2023. Please visit the Eventbrite page for:

More information

The BGS Coasts and Estuaries geohazards team provides independent and expert geoscientific tools and advice for collaborative decision making to assess different adaptation options for coastal flooding and erosion.

About the authors

Further reading

In our previous posts, we shared a broad overview of our coastal regions, with examples of our coastal environments and potential future changes. Here, we dig a little deeper into more specific vulnerabilities and focus on how our new GeoCoast data product can support coastal management and adaptation initiatives. This new dataset has been designed to assist future planning, with resilience considerations based on the natural geological characteristics of the coastal region.

Low-lying areas

Low-lying coastal areas are already vulnerable to inundation (flooding by the sea). However, with increasing sea levels and storminess, impacts could be felt over a wider area than we think.

• Many dune sites are already in fragile equilibrium
• Damage to infrastructure, agricultural production and a loss of homes and businesses could be felt
• Groundwater levels at the coast are likely to rise, and the combination of rising groundwater and inundation from the sea, mean that flooding events could become more severe, extensive and prolonged
• Groundwater is also likely to become more saline (salty), causing added pressure on water resources, which in some parts of the UK are already critical (e.g. )

Shoreline defences

Shoreline defences and their management are also under threat in many areas. How long can we continue to repair defences or implement new schemes; to what extent can we manage the realignment — or should we let nature take its course and adapt rather than resist? In a 2015 report, the to help understand whole-life costing in flood risk management, including coastal erosion and protection.

There are many factors affecting our coastline and its resilience to these factors has been an ongoing debate for many years. Climate scenarios (UKCP18) predict that sea levels will continue to rise, wave heights will increase and freak storms might become more regular events by 2080 and 2100.

Human influence

Humans may come and go but the underlying, fundamental natural deposits — the geology — will always remain an important factor to consider. A sea wall might be currently protecting weak sediments, but if that sea wall is breached or no longer maintained, we need to know where and what is vulnerable and how we can adapt the area to be more resilient.

Impacts of climate change

The effects of climate change have been seen around our coastline: Happisburgh in Norfolk has (around 35 homes) over the years and Norfolk has a long history of coastal erosion dating back centuries, for example with the so-called ‘lost villages of Norfolk’ (Eccles; Keswick; Waxham Parva; Newton; Foulness; Ness; Shipden, and Clare). Birling Gap in Sussex has lost its terraces and the , perched above the English Channel, was moved 17 m inland in 1999 to protect it from the failing cliff.

Important structures and assets are strongly protected and have multimillion pound budgets to accommodate this. For example, the Bacton sandscaping scheme in 2019 cost around £22 million, raising the beach level by about 7 m in places, and protects the gas terminal and adjacent village. It is estimated it will only be effective for the next 20 years.

The National Trust has funded several rebuilds of the harbour wall at Mullion Cove, Cornwall, costing over £2 million, as winter storms become more frequent and stronger. The trust has recognised that there may come a point where rebuild is no longer financially possible.

How will the GeoCoast data product help?

GeoCoast is an integrated GIS package of datasets designed to inform and support coastal management and adaptation. Targeted at coastal practitioners, including regulatory bodies, local authorities, asset owners and also home owners who want to be better informed, GeoCoast can be used to underpin coastal decision making and planning relative to coastal inundation, erosion and climate change impacts. The datasets are compatible with shoreline management plan areas.

Coastal erosion

Coastal erosion is a real issue and is only set to increase under future climate change scenarios. There are some 133 km², or 15.5 per , of coastline that are classed as having a high susceptibility to erosion, much of which are located around the east, south-east and north-east coasts. A further 195 km², or 22 per cent, are classed within the moderate-high category. Some are defended; others are not.

Even if defences are maintained, this is a staggering amount of coastline under threat and there are some 30 000 properties within 25 m of potentially highly susceptible coast. Counties such as Lincolnshire, Hampshire, Norfolk and Lancashire have a high percentage of low-lying, weak, coastal landforms that are at potential risk from increased storminess and wave attack.

GeoCoast includes information on the morphology, behaviour and vulnerability of the coastline, underpinned by its geology and its coastal context (shape; slope; range, etc.) We have carried out a detailed analysis of the coastline sediments and cliff sections, and identified the changes of coastal stratigraphy that are stacked in cliff sections.

Geology maps only identify the uppermost geology, whereas GeoCoast considers the whole sequence from beach level or sea level, to the top of the cliff or coastal deposit. For example, parts of the Jurassic Coast in Dorset have sequences, from beach level to cliff top, of:

• Charmouth Mudstone Formation
• Eype Clay Member
• Downcliff and Thorncombe Sand Members
• Gault Formation
• Upper Greensand Formation

Each of these lithologies has different properties and different levels of resistance to coastal erosion, which, in turn, affect the resilience of the coastline and how it responds.

Coastal subsidence

The potential for coastal zones to undergo subsidence due to natural processes of compaction, dissolution, and shrinkage of geological deposits, has been linked with variations in sea level.

The coastal subsidence analysis combines satellite-measured movement with lithological data to generate levels of potential and measured movement (mm/yr).

Coastal floods

We have carried out extensive characterisation and modelling of the coast of Great Britain, considering many aspects of the coastal zone and its underpinning geology and sediments. Future sea-level rise has been modelled using UKCP18 SLR scenarios (RCP4.5) to provide an estimate of coastal inundation (nationally) of approximately 7258 km² by the 2050s, 7768 km²in the 2080s and 8145 km² by 2100.

Looking at the worst-case scenario and not taking into account defences, our data also suggests that some one million properties are at potential risk from inundation by 2050, increasing to 1.25 million by the 2080s and 1.35 million by 2100 if no protective measures are implemented.

More examples of the datasets can be viewed in our case studies, available as ESRI Storymaps.

To find out more about our GeoCoast data product, including to arrange sample datasets or licensing, please get in touch with us at digitaldata@bgs.ac.uk.

Read previous entries in this blog series:

• Six changing coastlines and how climate change could affect them
• Sea level rise and coastal erosion: what the real impact?

Join us for our GeoCoast launch event

Join our data products team for a live webinar on the 28 April 2022, and discover more about our new data product to underpin coastal decision making, resilience and adaptation. > Register online

About the author

In our last post, we looked at the coastline of Great Britain, how it is changing and what important factors we should consider in terms of natural hazards, adaptation and resilience. In this article, we visit six key examples of natural environmental importance and explore their potential vulnerability to climate change.

The coastline of Great Britain, including its islands, is 31 368 km long, according to the Ordnance Survey (OS), with the mainland making up 17 819 km. Cornwall is the county with the longest coastline (1086 km) followed by Essex (905 km) and Devon (819 km). Our island nation experiences some of the largest tides in the world, with a range of up to 15 m, and a variety of geohazards and processes regularly have an impact on the changing coastline.

51ÁÔÆæ has mapped the whole of the British coastline and now a new data product, GeoCoast, brings a whole range of data together into one package to help inform and interpret our coastal environment.

Spurn Point, East Yorkshire

Overview

Spurn Point is three miles long, forming a natural protection for the Humber estuary and the port of Hull, as well as being an important site for migratory birds and other wildlife. It is an ever-changing environment composed of shingle beach and tidal flat deposits that is highly susceptible to coastal retreat. Formed as a long, narrow spit from deposits moving along the coast carried by currents, it has been breached by storms multiple times, notably in December 2013 by a huge tidal surge, bursting through the narrowest part of the spit and destroying the road.

A changing climate

Sea-level rise is predicted to completely cut off Spurn Head by 2050, according to modelled .

More information

• Spurn Discovery Centre, Spurn Road, Kilnsea, Hull HU12 0UH
• Get there: take the A1033 from Hull

Flamborough Head, East Yorkshire

Overview

Further north from Spurn Point, the geology at Flamborough Head comprises chalk cliffs capped by deposits of glacial till. Here, the chalk is more resistant to erosion than the overlying till, which is often unstable and can be susceptible to landslides.

A changing climate

Increased rainfall could increase the sensitivity of the till deposits to destabilisation. In addition, increased wave activity and storminess could impact the chalk at wave level, creating undercutting and cavities, which will eventually destabilise parts of the cliff.

More information

• Visit just a few miles from Flamborough Head. The nature reserve is characterised by its stunning array of wildlife, a flint boulder beach and chalk cliffs with fossils
• Flamborough Head car park, Flamborough, Bridlington YO15 1AR
• Get there: the nearest train station is Flamborough, or take the B1259

Holkham, Norfolk

Overview

Miles of empty dunes and sandy beaches at low tide, alongside estuaries, tidal creeks and salt marshes, Holkham is one of the most beautiful stretches of sand in England. This unique stretch of coastline attracts numerous nature lovers, walkers, horse riders and film makers. Some four miles long, the white sandy beach is backed by high dunes and pine woods, creating an important habitat, and is a designated Site of Special Scientific Interest (SSSI). The geology consists of tidal deposits, tidal flat and sand dunes, all with high susceptibility to coastal erosion and inundation.

The Holkham area suffered devastating consequences from floods in 1953 and 1978, then again on 5 December 2013 when a tidal surge flooded shops and homes in neighbouring Wells-next-the-Sea.

A changing climate

Continued effects of climate change are projected to see increased sea-level rises, resulting in a higher tidal reach into the tidal marshes and even higher storm surges, which could flood sensitive habitats, campsites and properties more frequently.

More information

• Get there: the nearest train stations are Cromer (25 miles) and Sheringham (19 miles). Take thh B1105 from the south or the A149 from the east/west. Use NR23 1RH in your satnav for parking

Tillingham marshes, Essex

Overview

The Dengie peninsula in Essex is a national nature reserve situated on low-lying land adjacent to the North Sea. There is evidence that the coastline was previously much further inland, as far as Tillingham village (which is 2 to 3 km from the coast). Earthen sea-wall embankments dating back to the Middle Ages have enabled the land to be reclaimed on the seaward side, forming an expansive area of saltmarsh, creeks and intertidal mudflats. This area is exposed to the waves and the saltmarsh landscape helps to attenuate the wave action, forming a natural defence against the sea.

The geology around this part of the coast is predominantly flat alluvial land, more gently undulating further inland with some steep slopes in the estuaries. The main superficial deposits are intertidal flats at the coast, fringed with saltmarsh with river terrace deposits and head landward, all underlain by the London Clay Formation.

A changing climate

Sea-level rises are accelerating erosion of the saltmarsh landward due to ‘coastal squeeze’ where the saltmarsh is eroded up against the seawall. The eroded sediment is then deposited on top of the existing saltmarsh and mudflats, building the height up on the seaward side so the marsh is higher than the land behind the seawall.

More information

• Get there: the nearest train station is Southminster, or take the B1021

Studland Bay, Dorset

Overview

Frequent winter storms have meant loss of sand from Studland Bay over many years and, in 2014, one of the worst winter storm surges in 35 years resulted in a loss of up to 10 m of dunes in just one storm. The coastline is composed of sand dunes and beach deposits, underlain by the Broadstone Clay Member. 

A changing climate

Projected increased sea-level rise and increased storminess will see the loss of these sand-rich deposits continue. The National Trust manages the coastline here and their focus is now on adaptation and the use of softer defences rather than the hard sea defences traditionally used.

More information

• Get there: you can reach Studland Bay on the B3351. Use BH19 3AH in your satnav for parking

Dungeness, Kent

Overview

Dungeness is situated at the southernmost point of Kent and is one of the most extensive examples of stable, vegetated shingle (gravel) in Europe, sheltering a large area of low-lying land.

Dungeness is almost entirely made up from flint shingle that has built up over the past six thousand years. The shingle has been redistributed over time forming a cuspate barrier, or ness, between its two shorelines. In addition to exposed shingle there are also buried shingle banks present. This barren landscape, with its landmark lighthouse, and also the site of a major nuclear power station, attracts around one million visitors annually.

The geology comprises predominantly storm beach and tidal flat deposits, alongside small amounts of blown sand and alluvium. These superficial deposits are underlain at depth by the Hasting Beds (sandstone, siltstone and mudstone).

A changing climate

Although some 30 per cent of the coastline is susceptible to erosion and 44 per cent (68km) could potentially be at risk of inundation by 2050, increasing slightly to 45 per cent (69km) by 2100, there is the requirement for continued sediment management to ensure the frontage at Dungeness nuclear power station is protected for the next 100 years..

More information

• Get there: the nearest train station is Rye, one mile from Lydd on the Dungeness road. Use TN29 9PN in your satnav for parking

Further information

In our next post, we will discuss how our new GeoCoast data product can be used to inform and assist users when responding to coastal adaptation and resilience.

GeoCoast is an integrated GIS package of datasets designed to inform and support coastal management and adaptation. It includes information about coastal erosion, sea level rise and inundation, coastal subsidence and the properties of the geological deposits.

Join us for our GeoCoast launch event

Join our data products team for a live webinar on the 28 April 2022, and discover more about our new data product to underpin coastal decision making, resilience and adaptation. > Register online

About the author

In this new series of blogs, the digital products team looks at the coastline of Great Britain, how it is changing and what important factors we should consider in terms of natural hazards, adaptation and resilience.

Coastal resilience is a key issue for our island nation, especially those who live and work around our coastline. The climate is changing, temperatures are increasing and sea-levels are set to rise. In recent years, we have witnessed numerous examples of coastal flooding, cliff falls and damage to infrastructure, businesses and homes during storms. But how much of an issue are these coastal vulnerabilities and what do we need to consider to increase our resilience to future events?

It is difficult to quantify the threat and potential economic impact of coastal erosion and flooding. The Climate Change Committee estimated in 2018 that, by the 2080s, over 100 000 properties may be in areas at risk from coastal erosion in England alone.

Various reports have been commissioned over recent years to assist in building a clearer picture of the situation and options to reduce this risk. The UK Government on exploratory sea-level projections for the UK provides future projection ranges to the year 2300. Under all scenarios, sea level is expected to continue to rise. Estimates range across (approximately):

• 0.5m to 2.2m for low () emissions
• 0.8m to 2.6m for medium-low () emissions
• 1.4m to 4.3m for high () emissions

To provide some context relating to the societal importance of our coastal regions, aside from their natural significance, we can consider some of the findings of a by a Select Committee appointed through the House of Lords. This group and the subsequent report had been set up to focus on the regeneration of seaside towns and communities, which included a review of tourism and hospitality. Based on this report and the associated proceedings, the following numbers can be ascribed to our coastal regions:

• more than eight million people live on the coast, in coastal communities ( (2018))
• according to , the sector employs 2.9million people and generates £130billion in economic activity
• VisitBritain stated that tourism was worth £127billion to the British economy ().

In the UK, current annual damages from coastal flooding are estimated at over £500million per year () and costs are likely to increase under projections of future sea-level rise. Historic assets are also under threat: buried archaeology and historic structures, such as the Godwin Battery on Spurn Point, have already been lost to coastal erosion. The following the 2013/14 winter storms amounted to some £250000, with other repairs costing many thousands of pounds.

Our new GeoCoast data product can be used to inform and assist users when responding to coastal adaptation and resilience. GeoCoast is an integrated GIS package of datasets designed to inform and support coastal management and adaptation. It includes information about coastal erosion, sea-level rise and inundation, coastal subsidence and the properties of the geological deposits.

Our next post in this series will look at six areas of changing coastlines around Great Britain and how climate change could affect them.

Join us for our GeoCoast launch event

Join our data products team for a live webinar on the 28 April 2022, and discover more about our new data product to underpin coastal decision making, resilience and adaptation. > Register online

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