UK Coastline Research Articles

Exploring nearshore bed dynamics of a mixed beach using the depth of closure conceptual model

Mixed sediment beaches are globally commonplace, yet little is understood of the extent and behaviour of their nearshore zones, potentially underestimating total cross-shore change. This paper is the first study to investigate the lateral and vertical extent of the active zone of the gravel-rich mixed beach in Pevensey Bay, a study site on the South East UK coastline. Morphodynamic change in the nearshore zone was studied at a range of timescales (days, months, years) suggesting that the width of the active nearshore zone correlated with the magnitude of the peak morphological change, whilst the depth of closure was influenced by bed slope, grain size and local variation in wave conditions. A conceptual model detailing the physical parameters responsible for local variations in the depth of closure was used to help understand differences between the observed and predicted depths of closure. Finally, ongoing chronic loss of sediment from below Mean Sea Level (MSL) was examined, which was shown to be independent of the depth of closure, but closely linked to the wider geomorphic setting of the bay.

Can samphire be the new salt? Understanding the potential of samphire harvested from the UK coastline

Salicornia species have been explored as a substitute for salt, however the intensity of salty taste elicited remains unexplained by the sodium content alone. To investigate this, a study was conducted to determine the nutrient profile of samphire extract and relate this to its sensory quality in a nachos base. Freeze dried samphire extracts contain minerals, including Na (12–14 g/100 g), K (1–1.5 g/100 g) and Mg (0.3–0.5 g/100 g) and free amino acids such as lysine (28–41 mg/100 g), glutamic acid (20–31 mg/100 g), aspartic acid (20–56 mg/100 g) and arginine (54–109 mg/100 g), which are known to influence salty taste. The sensory panel found that 2.5 % addition of samphire extract produced a significantly saltier taste than the control product (0.7 % NaCl) at an equivalent sodium level. These findings suggest that the minerals and amino acids in samphire extract may collectively contribute to its salty taste, making it a viable option for reducing sodium in food products.

Un-muddying the waters: Using benthic and shorebird population data to assess intertidal mudflat conditions and inform management strategies in two Irish Sea marine protected areas

Intertidal mudflats are highly productive coastal habitats, serving as a transition zone between terrestrial and marine ecosystems and providing a wealth of ecosystem services, including providing nursery and feeding grounds for many species of conservation and commercial importance. These habitats are important for wintering shorebirds and waders, which depend on them for food, nesting, and migration. Their importance was formally recognised in 1971 following the Ramsar Convention on Wetlands of International Importance, yet their conservation status remains largely uncertain as they are difficult to survey, and a complete understanding of their complex biophysical processes has yet to be established. While intertidal mudflats are found all around the UK coastline, there are few routine field surveys of these habitats, making effective conservation in the face of rising anthropogenic and climate pressures challenging. Marine protected areas (MPAs) across the UK list mudflats and sandflats not covered by seawater at low tide as a designation feature separate from saltmarshes, but they are often managed together – where management exists. A lack of resources has resulted in several paper parks around the UK, where MPAs are designated but not adequately monitored or managed. This study explores the use of population data of benthic species and shorebirds as a proxy for temporal changes in mudflat conditions, focusing on two MPAs in the Irish Sea, Strangford Lough in Northern Ireland, and the Solway Firth in Scotland/England. It finds that the two methods together can provide information useful to support MPA management, but this approach is hampered by poor availability of sufficient data. Such data limitation can impact what it means to achieve or maintain favourable conditions for these habitats.

The temporal clustering of storm surge, wave height, and high sea level exceedances around the UK coastline

The temporal clustering of storms presents consecutive storm surge and wave hazards that can lead to amplified flood and erosional damages; thus, clustering is important for coastal stakeholders to consider. We analyse the prevalence of storm clustering around the UK coastline by examining the temporal and spatial characteristics of storm surge, wave height, and high still sea level exceedances at the 1 in 1- and 5-year return levels. First, at the interannual timescale, we show that there are periods of high/low exceedance counts on national and regional scales. Elevated annual counts of exceedances with smaller magnitudes can occur without a respective signal of higher-magnitude exceedances. Secondly, at the intra-annual timescale, we show that high proportions of exceedances are clustering over short timescales. Storm surge, wave height and still sea level exceedances occurring < 50 days after the prior exceedance at a given site account for between ~ 35–44% and ~ 15–22% of all exceedances at the 1 in 1- and 5-year return levels, respectively. Still sea levels have the highest proportion of exceedances clustered in quick succession, with ~ 25% of 1 in 1-year exceedances occurring < 2 days after the previous at the same site. Spatially, for UK storm surges and still sea levels, the North Sea has the lowest proportion of clustering, whereas the North Atlantic and Bristol Channel have the highest. For English wave records, the highest proportions of clustering are found in the North Sea for exceedances of a lower magnitude and the English Channel for exceedances of a higher magnitude. These findings illuminate the prevalence of the clustering of coastal hazards around the UK—helping coastal stakeholders evaluate the threat of surges, waves, and sea levels clustering over short periods.

Towards using state-of-the-art climate models to help constrain estimates of unprecedented UK storm surges

Abstract. Our ability to quantify the likelihood of present-day extreme sea level (ESL) events is limited by the length of tide gauge records around the UK, and this results in substantial uncertainties in return level curves at many sites. In this work, we explore the potential for a state-of-the-art climate model, HadGEM3-GC3, to help refine our understanding of present-day coastal flood risk associated with extreme storm surges, which are the dominant driver of ESL events for the UK and wider European shelf seas. We use a 483-year present-day control simulation from HadGEM3-GC3-MM (1/4∘ ocean, approx. 60 km atmosphere in mid-latitudes) to drive a north-west European shelf seas model and generate a new dataset of simulated UK storm surges. The variable analysed is the skew surge (the difference between the high water level and the predicted astronomical high tide), which is widely used in analysis of storm surge events. The modelling system can simulate skew surge events comparable to the catastrophic 1953 North Sea storm surge, which resulted in widespread flooding, evacuation of 32 000 people, and hundreds of fatalities across the UK alone, along with many hundreds more in mainland Europe. Our model simulations show good agreement with an independent re-analysis of the 1953 surge event at the mouth of the river Thames. For that site, we also revisit the assumption of skew surge and tide independence. Our model results suggest that at that site for the most extreme surges, tide–surge interaction significantly attenuates extreme skew surges on a spring tide compared to a neap tide. Around the UK coastline, the extreme tail shape parameters diagnosed from our simulation correlate very well (Pearson's r greater than 0.85), in terms of spatial variability, with those used in the UK government's current guidance (which are diagnosed from tide gauge observations), but ours have smaller uncertainties. Despite the strong correlation, our diagnosed shape parameters are biased low relative to the current guidance. This bias is also seen when we replace HadGEM3-GC3-MM with a reanalysis, so we conclude that the bias is likely associated with limitations in the shelf sea model used here. Overall, the work suggests that climate model simulations may prove useful as an additional line of evidence to inform assessments of present-day coastal flood risk.

The Brown Seaweeds of Scotland, Their Importance and Applications

More than 50% of the UK coastline is situated in Scotland under legislative jurisdiction; therefore, there is a great opportunity for regionally focused economic development by the rational use of sustainable marine bio-sources. We review the importance of seaweeds in general, and more specifically, wrack brown seaweeds which are washed from the sea and accumulated in the wrack zone and their economic impact. Rules and regulations governing the harvesting of seaweed, potential sites for harvesting, along with the status of industrial application are discussed. We describe extraction and separation methods of natural products from these seaweeds along with their phytochemical profiles. Many potential applications for these derivatives exist in agriculture, energy, nutrition, biomaterials, waste treatment (composting), pharmaceuticals, cosmetics and other applications. The chemical diversity of the natural compounds present in these seaweeds is an opportunity to further investigate a range of chemical scaffolds, evaluate their biological activities, and develop them for better pharmaceutical or biotechnological applications. The key message is the significant opportunity for the development of high value products from a seaweed processing industry in Scotland, based on a sustainable resource, and locally regulated.

Can Rock-Rubble Groynes Support Similar Intertidal Ecological Communities to Natural Rocky Shores?

Despite the global implementation of rock-rubble groyne structures, there is limited research investigating their ecology, much less than for other artificial coastal structures. Here we compare the intertidal ecology of urban (or semi-urban) rock-rubble groynes and more rural natural rocky shores for three areas of the UK coastline. We collected richness and abundance data for 771 quadrats across three counties, finding a total of 81 species, with 48 species on the groynes and 71 species on the natural rocky shores. We performed three-way analysis of variance (ANOVA) on both richness and abundance data, running parallel analysis for rock and rock-pool habitats. We also performed detrended correspondence analysis on all species to identify patterns in community structure. On rock surfaces, we found similar richness and abundance across structures for algae, higher diversity and abundance for lichen and mobile animals on natural shores, and higher numbers of sessile animals on groynes. Rock-pool habitats were depauperate on groynes for all species groups except for sessile animals, relative to natural shores. Only a slight differentiation between groyne and natural shore communities was observed, while groynes supported higher abundances of some ‘at risk’ species than natural shores. Furthermore, groynes did not differ substantially from natural shores in terms of their presence and abundance of species not native to the area. We conclude that groynes host similar ecological communities to those found on natural shores, but differences do exist, particularly with respect to rock-pool habitats.

Lifeform indicators reveal large-scale shifts in plankton across the North-West European shelf.

Increasing direct human pressures on the marine environment, coupled with climate-driven changes, is a concern to marine ecosystems globally. This requires the development and monitoring of ecosystem indicators for effective management and adaptation planning. Plankton lifeforms (broad functional groups) are sensitive indicators of marine environmental change and can provide a simplified view of plankton biodiversity, building an understanding of change in lower trophic levels. Here, we visualize regional-scale multi-decadal trends in six key plankton lifeforms as well as their correlative relationships with sea surface temperature (SST). For the first time, we collate trends across multiple disparate surveys, comparing the spatially and temporally extensive Continuous Plankton Recorder (CPR) survey (offshore) with multiple long-term fixed station-based time-series (inshore) from around the UK coastline. These analyses of plankton lifeforms showed profound long-term changes, which were coherent across large spatial scales. For example, 'diatom' and 'meroplankton' lifeforms showed strong alignment between surveys and coherent regional-scale trends, with the 1998-2017 decadal average abundance of meroplankton being 2.3 times that of 1958-1967 for CPR samples in the North Sea. This major, shelf-wide increase in meroplankton correlated with increasing SSTs, and contrasted with a general decrease in holoplankton (dominated by small copepods), indicating a changing balance of benthic and pelagic fauna. Likewise, inshore-offshore gradients in dinoflagellate trends, with contemporary increases inshore contrasting with multi-decadal decreases offshore (approx. 75% lower decadal mean abundance), urgently require the identification of causal mechanisms. Our lifeform approach allows the collation of many different data types and time-series across the NW European shelf, providing a crucial evidence base for informing ecosystem-based management, and the development of regional adaptation plans.

Trading off visual disamenity for renewable energy: Willingness to pay for seaweed farming for energy production

We studied people's preferences to support a renewable energy programme to grow seaweed for biogas production, using a choice experiment. Participants had to choose one among three alternatives, two of which were variations of a seaweed programme and the third was the status quo. The two alternatives were defined in terms of four attributes: the number of households powered, the percentage of coastline used to farm seaweed, the additional cost they would incur and perks, which were added to encourage people to participate in the programme. The choice experiment was conducted online in England, Scotland and Northern Ireland among 2016 respondents. The compensating variation from a renewable energy programme from seaweed that powers 85,000 households and covers 20% of the UK coastline is £16 per year in England, £16 per year in Scotland and £14 per year in Northern Ireland, respectively. We find that people are willing to use more coastline to farm seaweed in order to power more households. That is, they are willing to make a trade-off between the visual disamenity caused by the seaweed farms and producing more green energy. Lastly, both perks have negative effects on people's preferences for using seaweed as biogas.

A Smooth Curve as a Fractal under the Third Definition

It is commonly believed in the literature that smooth curves, such as circles, are not fractal, and only non-smooth curves, such as coastlines, are fractal. However, this article demonstrates that a smooth curve can be fractal, under a new, relaxed, third definition of fractal – a set or pattern is fractal if the scaling of far more small things than large ones recurs at least twice. The scaling can be rephrased as a hierarchy, consisting of numerous smallest, a very few largest, and some in between the smallest and the largest. The logarithmic spiral, as a smooth curve, is apparently fractal because it bears the self-similarity property, or the scaling of far more small squares than large ones recurs multiple times, or the scaling of far more small bends than large ones recurs multiple times. A half-circle or half-ellipse and the UK coastline (before or after smooth processing) are fractal if the scaling of far more small bends than large ones recurs at least twice.

Coastal and estuarine management in the UK: review and overview of perspectives

The UK is a coast-dominated country which is relatively well endowed with estuaries on the account of its varied geology. Coasts and estuaries are the example of typical environments which have attracted growing concerns in recent times because of the prevalence of anthropogenic and intense physical processes pressures. Various coastal and estuarine management techniques are being employed to address the challenges imposed by these pressures. This paper presents the overview and reviews of the management strategies and interventions being adopted for the UK coastline and estuarine environments.

Molecular identification of Didemnum vexillum Kott, 1982 from sites around the UK coastline

Didemnum vexillum Kott, 1982 is a tunicate known as the carpet sea squirt that is non-native to the UK. It has been reported from sites in the UK and Ireland based on morphological characteristics. Here we present the results of Cytochrome Oxidase I mitochondrial gene analyses to confirm species identification of specimens taken from several of the sites around the UK mainland coast where non-native tunicate colonies have been reported. The results confirm the identity of the UK carpet sea squirt samples as Didemnum vexillum and provide additional information on COI haplotypes present in the UK.

The incentives of a resource owner: Evidence from a private oyster fishery

European flat oyster Ostrea edulis fisheries were once abundant around the UK coastline. The sole remaining productive O. edulis fishery in Scotland is in Loch Ryan. This fishery has been privately owned and managed by a single family since 1701. Economic theory predicts that ownership, whether public or private, is a necessary condition for rational fishery management. In this paper, a series of four leases and a licence are examined, covering an 85-year period over the 20th and 21st century, to examine whether the management of the Loch Ryan fishery conforms to the expected norms of rational management. The leases show that, over this period, the owners appear more willing to expend resources on regulating tenant behaviour, supporting the conclusion that successive generations of owners developed an evolving sense of what “rational management” might require. The results of this study could inform the management of other fisheries – both public and private – by emphasising the importance of learning from experience.

Importance of decadal scale variability in shoreline response: examples from soft rock cliffs, East Anglian coast, UK

Rapidly eroding soft rock cliffs typically retreat at rates in excess of several metres per year, thus allowing the resolution of linkages between cliff dynamics and a range of climatic and marine forcing factors. New evidence from UK coastline of East Anglian coastline, southern North Sea shows that unprotected soft rock cliffs at three widely-spaced locations all show similar variability in retreat behaviour on decadal timescales, which we attribute to changing patterns of storminess in these decades. The 1990s were characterized by frequent months in which the North Atlantic Oscillation (NAO; a well-established measure of inter-annual climatic variability in North-West Europe) was extremely positive (more positive than +3) or extremely negative (more negative than −3), while the 2000s showed few occurrences of such extreme values. Depression tracks in positive NAO phases make the East Anglian coast prone to storm surges in which raised water levels result from deeply developed low pressure systems, generally associated with westerly air streams. In negative NAO phases the region is prone to easterly airflow which results in periods of strong onshore wind. Both phases are associated with high energetics in the forcing factors. Decadal-scale variability in cliffline retreat rates has implications for the practice of coastal management and policy making and suggests that cliff system responses to global environmental change are not simply driven by secular sea level rise.

Molecular characterization of poxviruses associated with tattoo skin lesions in UK cetaceans.

There is increasing concern for the well-being of cetacean populations around the UK. Tattoo skin disease (characterised by irregular, grey, black or yellowish, stippled cutaneous lesions) caused by poxvirus infection is a potential health indicatora potential health indicator for cetaceans. Limited sequence data indicates that cetacean poxviruses (CPVs) belong to an unassigned genus of the Chordopoxvirinae. To obtain further insight into the phylogenetic relationships between CPV and other Chordopoxvirinae members we partially characterized viral DNA originating from tattoo lesions collected in Delphinidae and Phocoenidae stranded along the UK coastline in 1998–2008. We also evaluated the presence of CPV in skin lesions other than tattoos to examine specificity and sensitivity of visual diagnosis. After DNA extraction, regions of the DNA polymerase and DNA topoisomerase I genes were amplified by PCR, sequenced and compared with other isolates. The presence of CPV DNA was demonstrated in tattoos from one striped dolphin (Stenella coeruleoalba), eight harbour porpoises (Phocoena phocoena) and one short-beaked common dolphin (Delphinus delphis) and in one ‘dubious tattoo’ lesion detected in one other porpoise. Seventeen of the 18 PCR positive skin lesions had been visually identified as tattoos and one as a dubious tattoo. None of the other skin lesions were PCR positive. Thus, visual identification had a 94.4% sensitivity and 100% specificity. The DNA polymerase PCR was most effective in detecting CPV DNA. Limited sequence phylogeny grouped the UK samples within the odontocete poxviruses (CPV group 1) and indicated that two different poxvirus lineages infect the Phocoenidae and the Delphinidae. The phylogenetic tree had three major branches: one with the UK Phocoenidae viruses, one with the Delphinidae isolates and one for the mysticete poxvirus (CPV group 2). This implies a radiation of poxviruses according to the host suborder and the families within these suborders.

A UK best-practice approach for extreme sea-level analysis along complex topographic coastlines

The impacts of storm surges represent an increasing risk to the world's coastlines. Coastal planners require accurate estimates of flood risk in order to provide suitable defensive measures. Therefore a reliable methodology is required for the estimation of extreme sea-level probabilities at high spatial resolution along coastlines. This paper describes a new method for estimating these probabilities, with application to the UK coastline. The method consists of two components: the estimation of extreme sea-levels by applying a newly developed statistical method, termed the Skew Surge Joint Probability Method, with tide gauge records, and the use of hindcast sea-levels to dynamically interpolate these estimates around complex coastlines. The skew surge parameter is a more reliable indicator of meteorological impacts on sea-level than the non-tidal residual used in the Revised Joint Probability Method, as previously used in the United Kingdom.The method has been applied to the UK coastline to provide a database of extreme sea-level probabilities for the Environment Agency for England and Wales and the Scottish Environment Protection Agency. The database will be used to inform coastal defense strategy, flood mapping and forecasting and to support policy, implementation and operational decision-making.

Paradise lost: threatened waves and the need for global surf protection

Nelsen, C., Cummins, A. and Tagholm H., 2013. Paradise Lost: Threatened Waves and the Need for Global Surf ProtectionOcean waves are an integral part of the marine system, providing recreation and economic values to coastal communities around the world. Worldwide, the importance of surfing is consistently undervalued. As a result, there are numerous examples around the world where surfing waves are currently under threat from inappropriate development. Many more surfing waves have already destroyed by development.There are numerous discreet threats to surfing waves around the UK coastline. UK-based Surfers Against Sewage (SAS) is promoting the value of waves with the Waves Are Resources (WAR) Report and the Protect Our Waves (POW) petition calling for specific legislation to better protect surfing waves around the UK.Internationally, the Surfrider Foundation successfully stopped a proposed six-lane toll road that would have destroyed a popular state park and degraded a world famous surfing area called Trestles. The project was opposed by thousands of water users, supported by a surf economics report. Surfers visiting Trestles contribute to San Clemente's local economy by spending money when they visit and contribute between $8 and $13 million a year to the local economy.This paper presents an overview of the importance of surfing to coastal communities, provides an overview of threats to surfing around the globe and cases studies on successful efforts to protect surfing through coastal management, planning and legislation. The findings demonstrate the significant economic, social and environmental importance of surfing amenity to specific locales and support the need for appropriate consideration of impacts to surfing that may occur as a result of coastal management decisions.

Recent UK experience of coastal cliff stabilisation

There are many locations on the UK coastline where the soil and weak rock cliffs are subject to erosion, and the resulting instability threatens both public safety and infrastructure. With predicted climate change, the impact of this erosion and instability will be an ever-increasing adverse affect on the coast. A total of 14 cliff sites are reviewed. Each site described, which includes sites comprising glacial deposits, reactivated post-glacial landslides and Jurassic and Cretaceous weak rock strata, has been stabilised using a combination of different techniques. This paper is a review of the methods of investigation and the approaches to the selection of the stabilisation techniques that have been used at each of the sites. In some cases the significance of the environmental status of the sites and its influence on the selection of stabilisation techniques is described. Some of the techniques, including piles, buttresses, drainage and reinforcement are discussed further, although comprehensive details of the majority of the sites are provided in site-specific publications given in the list of references.

Consequences of short‐term changes in coastal processes: a case study

AbstractIn 1997–98, unique critical beach erosion led to structural failure along the Penarth, South Wales, UK coastline and anthropogenic activities, such as the construction of the Cardiff Bay Barrage and offshore marine aggregate dredging, were suggested as causes. The time‐frame of significant erosion was between 1995 and 1997 and forcing agents (extreme sea level and wind direction) and shoreline indicators (mean beach level and MHW) were analysed in order to assess change. Water level analysis showed that although there was no significant difference between actual and predicted mean sea levels, extreme sea levels at that time were significantly higher (t = 3·305; d.f. = 8; p &lt; 0·05). Three wind direction analyses (annual mean, mean annual maximum gust and mean annual maximum gust ≥28 kn) between 1995 and 1997 also showed significant differences (p &lt; 0·05). All comprised more easterly components which meant they approached the beach from the sea. Furthermore, gusts ≥28 kn from the northeast quadrant, that is, 0° to 90° true, were significantly more frequent during these years (t = 3·674; d.f. = 8; p &lt; 0·01). Justification of statistical significances was established and there was supporting evidence of unusual meteorological conditions at that time. Relationships showed correlation between forcing agents (extreme sea level and wind direction) and shoreline indicators (mean beach level and Mean High Water). Furthermore, regression analysis showed winds from the northeast quadrant resulted in steeper longshore gradients, as a consequence of beach material loss. Therefore, it was concluded that the critical erosion of Penarth beach between 1995 and 1997 was caused by increased wave attack from the northeast and southeast quadrants, generated by unique significant changes in wind direction and extreme sea levels. Copyright © 2008 John Wiley &amp; Sons, Ltd.

Understanding user engagement with barcoded signs in the ‘Coast’ location-based experience

This article describes experiences with an application in which users read barcoded signs with camera phones to obtain content about their surroundings at seaside locations. The application was made available to the general public in support of ‘Coast’, a BBC television series about the UK coastline. The article highlights lessons from that trial in terms of what worked well and what was subject to deployment constraints. In particular, it describes how several factors affected the users’ engagement with the signs, the places, and other users: the barcode and mobile phone technologies; semantic issues such as signs’ relationships to landmarks; and practical issues such as local regulations.