Holderness Coast Research Articles

Rapid erosion along Holderness coast of East Yorkshire, UK and rising eustatic sea levels driven by climate change

Following the end of the last ice age, decelerating global post‐glacial sea level rises submerged the southern North Sea, and along this coast, 63 km of soft glacial deposits are still being rapidly washed away. The collapse of the massive ice sheets covering Britain, Ireland and Fennoscandia was a complex process, with warming after 14.7 ka. Limited glaciation then returned during the Loch Lomond Stadial at the end of the Pleistocene, Doggerland, connecting Britain with the continent, was slowly immersed, becoming a shrinking island which was rapidly submerged after 8 ka. This coincided with the Storegga tsunami which hit what remained of Doggerland’s shores and along the coasts of Scotland and Northumberland. Since then, the sea has risen by around 27.5 m. Now it is clear eustatic increases in global sea levels are starting to accelerate once again, we must start adjusting to this reality in the way we manage our coastal infrastructure and try to understand more about how this interacts with naturally dynamic shorelines.

A litho-tectonic event stratigraphy from dynamic Late Devensian ice flow of the North Sea Lobe, Tunstall, east Yorkshire, UK

The central sector of the British-Irish Ice Sheet during the last glaciation was characterised by complex ice-flow reflecting interacting ice streams and changing dominance of different ice dispersal centres. At Tunstall, east Yorkshire, two subglacial till units have been traditionally identified as the Late Devensian Skipsea and Withernsea tills, and thought to record two separate ice advances onto the Holderness coast, from divergent ice flow directions. Our study presents the first quantitative lithological, sedimentological and structural evaluation of glacial sediments at the site. The lithological composition of both till units suggests that ice extended southwards from southern Scotland, incorporating material from north-east England and the western margin of the North Sea Basin. Notably, the bulk lithological properties of both the Skipsea and Withernsea tills are very similar. Subtle variations in colour, texture and lithology that do occur simply appear to reflect spatial and temporal variability in subglacial entrainment along the flow path of the North Sea Lobe. The relative arrangements of the units plus the fracture sets also indicates phases of intra-till thrust-stacking and unloading (F2), consolidation and shrinkage (F1, F3) suggestive of cycles of ice re-advance (thrusting) and ice-marginal retreat (unloading and shrinkage) possibly relating to active recession. The findings from this study reveal a sedimentary and structural complexity that is not recognised by the current Late Devensian till stratigraphy of east Yorkshire.

Coastal landslide monitoring at Aldbrough, East Riding of Yorkshire, UK

The paper describes results to date of a continuing monitoring study of coastal ‘soft cliff’ recession at the British Geological Survey's (BGS's) Coastal Landslide Observatory (CLO) on the east coast of England at Aldbrough, East Riding of Yorkshire. The cliffed site, part of the 50 km long Holderness coast, consists of glacial deposits, and is one of the most rapidly eroding coastlines in Europe. This rapid rate of erosion provides an ideal opportunity for observation and process understanding because it facilitates the collection of data over periods of time encompassing significant new landslide events at the same location. The results of two approaches are reported: first, terrestrial Light Detection and Ranging (LiDAR) surveying (TLS); second, the installation of instrumented boreholes. The aim of the research is to combine these to investigate the role of landslides and their pre-conditioning factors and the influence of geology, geotechnics, topography and environmental factors on cliff recession. To date, an average recession rate of 1.8 m a −1 and a maximum rate of 3.4 m a −1 have been recorded for the site. The establishment of the CLO and its conceptual geological–geotechnical model are described in a related paper.

Establishment of a coastal landslide observatory at Aldbrough, East Riding of Yorkshire, UK

The paper describes the establishment of the British Geological Survey (BGS)’s field-based ‘Coastal Landslide Observatory’, designed for the study of coastal ‘soft cliff’ recession on the east coast of England at Aldbrough, East Riding of Yorkshire. The cliffed site is part of the 50 km long Holderness coast which is one of the most rapidly eroding coastlines in Europe. The site features a 16–17 m high sea-cliff formed by Late Devensian (18–13 ka) glacial deposits dominated by tills. The aim of the research is to investigate the role of landslides and their pre-conditioning factors, including geology, geotechnics and topography, in cliff recession with a view to developing coastal landslide forecasting capability. Two research approaches are encompassed in the observatory: firstly, terrestrial LiDAR surveying, from 2001 to present, to create digital elevation models of the cliff and, secondly, installation of instrumented boreholes from 2012. The design, methods, conceptual ground model, implementation of the observatory and geotechnical laboratory test results are described in this article. The interpretation of results and the final ground model are presented in a related article in this volume.

Diamicton from the Vale of Pickering and Tabular Hills, north-east Yorkshire: evidence for a Middle Pleistocene (MIS 8) glaciation?

Diamicton deposits (up to 6.90m thick) in the Vale of Pickering and the Tabular Hills (North York Moors) have been confirmed by cored boreholes. The diamicton is interpreted as glacial till with a matrix consisting predominantly of grey-brown, yellow-brown and dark grey, stiff to very stiff clay and sandy clay with occasional thin beds of laminated sand and clay. Sub-rounded to sub-angular erratic clasts were sourced predominantly from local Upper Jurassic Corallian Group bedrock exposed in the southern part of the North York Moors. Clasts include well-rounded, pebbles of Jurassic sandstone, mudstone and sparse Jurassic coal derived from outcrops on the North York Moors. Fragments of underlying Upper Jurassic mudstone bedrock form the predominant clasts in the lower part of the till. The paucity of exotic clasts and a local derivation suggests a relatively small glacier – perhaps a temperate-plateau ice-field, was established on the Tabular Hills. The glacier subsequently advanced southwards to the Vale of Pickering depositing locally derived subglacial traction till at the base, passing up to lodgement till. Local preservation of the degraded till outcrops in the Vale of Pickering, the overconsolidated nature of the clay till matrix, striated pebbles and the presence of sub-rounded pebbles suggests deposition during a glacial cold stage post-MIS 12 (Anglian) and pre-MIS 2 (Devensian). A tentative Middle Pleistocene MIS8 age is proposed, possibly coeval, but not coincident, with the Basement Till (Bridlington Member) of the Holderness coast and the Wragby Till of central and eastern England.

Spatial and temporal variations in soft-cliff erosion along the Holderness coast, East Riding of Yorkshire, UK

The Holderness coast is composed largely of ‘soft’ Quaternary sediments, mainly glacial till, which form cliffs up to 38 m high. Cliff erosion rates have shown a complex pattern of spatial and temporal variation over the past 160 years which reflects interaction of natural processes and human interventions, notably building of coastal defences at Bridlington, Hornsea, Withernsea, Mappleton, and Easington. A former single coastal cell, extending between Flamborough Head and the Spurn Peninsula, is breaking down into a series of separate sub-cells defined by sections of defended coast. Between these ‘hard points’ the shoreline is developing as a series of shallow bays which are deepest immediately to the south (downdrift) of the defences. Superimposed on this pattern are smaller-scale variations which reflect the effects of dynamic beach features on wave energy exposure at the cliff toe. Cliff recession rates can exceed 4 m a−1 when beach troughs lie in front of the cliff toe but may fall close to zero as a sand wave passes. Erosion rates on the undefended coast showed an increase in the period 1989–2013 compared with earlier epochs and further increases can be anticipated due to sea level rise over the course of the next century. The effects of climate change on storminess remain uncertain but any increase would further enhance the erosional trend. The implications are future increased rates of cliff top recession and increased risk to infrastructure close to the coast in the medium to longer term. Increased erosion rates will increase the rate of sediment supply to the nearshore system, but it is unclear how much of the fine sediment released will be transported into the Humber estuary to maintain tidal flats and saltmarshes, and how much of the sand and gravel will travel along the beach system to sustain the Spurn Peninsula.

Pleistocene till provenance in east Yorkshire: reconstructing ice flow of the British North Sea Lobe

The ice flow path and dynamic behaviour of the British-Irish Ice Sheet has been subject to renewed interest and controversy in recent years. Early studies in eastern England argued for interaction with Fennoscandian ice onshore in Britain, instigating re-examination of the sedimentology and provenance of many Pleistocene till successions. These studies instead supported an exclusively British provenance, and are used to predict southward advance of a broadly coast-parallel North Sea Lobe. Quantitative lithological and palynological analysis of the Pleistocene till succession in Holderness, East Yorkshire, however, remains to be carried out. We examined the lithologically diverse Skipsea Till in order to reconstruct ice flow pathways to the Holderness coast during the Pleistocene, thereby constraining which areas of substrate were subglacially eroded and entrained prior to deposition. The till yields a diverse range of soft, low-durability and uniquely British allochthonous material, including Permian Magnesian Limestone, Carboniferous limestone and coal, and Carboniferous pollen and spore assemblages that would be unlikely to survive polyphase reworking. Ice extended southwards through southern Scotland, incorporating material in north-east England, north-east Yorkshire and the western margin of the North Sea Basin (NSB), supporting a recurrent ice flow pathway for the eastern margin of the British-Irish Ice Sheet during the Mid to Late Pleistocene.

Measurement of historical cliff-top changes and estimation of future trends using GIS data between Bridlington and Hornsea – Holderness Coast (UK)

A key requirement for effective coastal zone management is good knowledge of historical rates of change and the ability to predict future shoreline evolution, especially for rapidly eroding areas. Historical shoreline recession analysis was used for the prediction of future cliff shoreline positions along a section of 9km between Bridlington and Hornsea, on the northern area of the Holderness Coast, UK. The analysis was based on historical maps and aerial photographs dating from 1852 to 2011 using the Digital Shoreline Analysis System (DSAS) 4.3, extension of ESRI’s ArcInfo 10.×. The prediction of future shorelines was performed for the next 40years using a variety of techniques, ranging from extrapolation from historical data, geometric approaches like the historical trend analysis, to a process-response numerical model that incorporates physically-based equations and geotechnical stability analysis. With climate change and sea-level rise implying that historical rates of change may not be a reliable guide for the future, enhanced visualization of the evolving coastline has the potential to improve awareness of these changing conditions. Following the IPCC, 2013 report, two sea-level rise rates, 2mm/yr and 6mm/yr, have been used to estimate future shoreline conditions. This study illustrated that good predictive models, once their limitations are estimated or at least defined, are available for use by managers, planners, engineers, scientists and the public to make better decisions regarding coastal management, development, and erosion-control strategies.

Coastal vulnerability of a pinned, soft-cliff coastline – Part I: Assessing the natural sensitivity to wave climate

Abstract. The impact of future sea-level rise on coastal erosion as a result of a changing climate has been studied in detail over the past decade. The potential impact of a changing wave climate on erosion rates, however, is not typically considered. We explore the effect of changing wave climates on a pinned, soft-cliff, sandy coastline, using as an example the Holderness coast of East Yorkshire, UK. The initial phase of the study concentrates on calibrating a numerical model to recently measured erosion rates for the Holderness coast using an ensemble of geomorphological and shoreface parameters under an observed offshore wave climate. In the main phase of the study, wave climate data are perturbed gradually to assess their impact on coastal morphology. Forward-modelled simulations constrain the nature of the morphological response of the coast to changes in wave climate over the next century. Results indicate that changes to erosion rates over the next century will be spatially and temporally heterogeneous, with a variability of up to ±25% in the erosion rate relative to projections under constant wave climate. The heterogeneity results from the current coastal morphology and the sediment transport dynamics consequent on differing wave climate regimes.

The unsteady nature of sea cliff retreat due to mechanical abrasion, failure and comminution feedbacks

Sea cliff retreat is often linked to large waves, heavy precipitation and seismic events, but the specific operative mechanics have not been well constrained. In particular, what is the role of mechanical abrasion by beach sediments in cliff/platform evolution and how does it relate to the episodic nature of cliff retreat observed at certain locations? Here we present a simple, numerical model of sea cliff retreat that incorporates mechanical abrasion of a basal notch, threshold-controlled failure of the cantilevered block, and a feedback mechanism wherein retreat is dependent on the rate of sediment comminution within the surf zone. Using shore platform and cliff characteristics found in two coastal settings (the central California coast and the English North Sea coast), the model produces retreat rates comparable to those observed via field measurements. The highest retreat rates coincide with the steepest shore platforms and increasing wave height. Steeper platforms promote wave access to the cliff toe and, correspondingly, the receding cliff face produces additional accommodation space for the platform beach, preserving the erosive efficacy of the beach sediments. When exposed to energetic wave forcing, the slope of the inner platform segment controls retreat rates for concave platforms, whereas the slope of the outer platform segment exerts greater control for convex platforms. Platform beaches approached a long-term dynamic equilibrium on the concave profiles, leading to more consistent and steady retreat. Platform beaches were ephemeral on convex profiles, mirroring observed sand wave (Ord) migration on the Holderness coast, UK. These findings agree with previous field observations and support mechanical abrasion as a viable cause of temporal heterogeneity in cliff retreat rate for both coastlines.

Coastal vulnerability of a pinned, soft-cliff coastline, II: assessing the influence of sea walls on future morphology

Abstract. Coastal defences have long been employed to halt or slow coastal erosion, and their impact on local sediment flux and ecology has been studied in detail through field research and numerical simulation. The non-local impact of a modified sediment flux regime on mesoscale erosion and accretion has received less attention. Morphological changes at this scale due to defending structures can be difficult to quantify or identify with field data. Engineering-scale numerical models, often applied to assess the design of modern defences on local coastal erosion, tend not to cover large stretches of coast and are rarely applied to assess the impact of older structures. We extend previous work to explore the influences of sea walls on the evolution and morphological sensitivity of a pinned, soft-cliff, sandy coastline under a changing wave climate. The Holderness coast of East Yorkshire, UK, is used as a case study to explore model scenarios where the coast is both defended with major sea walls and allowed to evolve naturally were there are no sea defences. Using a mesoscale numerical coastal evolution model, observed wave-climate data are perturbed linearly to assess the sensitivity of the coastal morphology to changing wave climate for both the defended and undefended scenarios. Comparative analysis of the simulated output suggests that sea walls in the south of the region have a greater impact on sediment flux due to increased sediment availability along this part of the coast. Multiple defence structures, including those separated by several kilometres, were found to interact with each other, producing complex changes in coastal morphology under a changing wave climate. Although spatially and temporally heterogeneous, sea walls generally slowed coastal recession and accumulated sediment on their up-drift side.

PROCESS–RESPONSE COASTAL BLUFF RECESSION MODEL, APPLICATION TO HOLDERNESS COAST (UK)

Coastal erosion and coastal instability, threatens property, businesses and life. Because of the great concentration of natural resources in coastal zones, it is imperative that coastal change is well understood to allow for effective management and, where necessary, engineering intervention. The development of cliff erosion predictive models is mainly limited to geomorphological data because of the complex interactions between coupled processes acting in time and space result in large-scale variations. There have been few reliable process-response models of cliff recession published. These have been based on functional relationships between the dominant physical processes covering the shoreface, beach and cliff or bluff, avoiding the geotechnical retreat mechanisms and behaviour within the cliff. Under this procedure, the resulting simulations of cliffs of differing behaviour can produce identical annual retreat characteristics despite the potential responses to a changing environment being unequal.
 
 According to this inconvenience, a new process-response recession model has been developed. It incorporates the behavioural characteristics of coastal rock cliffs, the geology of which is dominated by overconsolidated clays and an associated protective talus wedge. This work brings together classic geotechnical stability analyses for rotational landslides called “Swedish” or “Fellenius” Method of slices among with collapse stability analysis for toppling mass failure. Once cliff material has fallen (landslide or toppling failure), colluvium formation at cliff foot is incorporated into the model using three different procedures, according to the geomechanical features of the weathered debris material. The first procedure is based on the friction angle for weathered materials; the second one is based on the angle of reach for landslides and the last one is based on field observations. The irregular recession cyclic pattern continues with the colluvium wedge erosion and the cliff profile steepening before a new failure occurs. Unlike previous models, the calibration parameter is restricted to account for hydrodynamic uncertainties from marine action and not includes the material strength. This new model introduces geotechnical parameters to evaluate the rock mass instability and failure through a safety factor, including RMR, cohesion, friction angle, uniaxial compressive strength of soil or rock mass of each geological component within the cliff, groundwater, etc. Among the capabilities of the model, it provides precise and stable responses to some of the inherent uncertainties in cliff or bluff recession processes, including those morphodynamics caused by different failure mechanisms, such as colluvium generation, groundwater influence, erosive tidal cycles and the cliff behaviour under changing climate conditions (i.e. sea level rise).
 
 In this work, the presented model is validated through profile evolution assessment at various locations of Holderness Coast, UK. The model reflects that the coastal oversteeping is a key factor of instability in coastal cliffs, accompanied by cliff height that determines the failure mechanism present in the study area. Higher sea levels would remove the previous failed material at the base of the cliff more quickly and cause the slope to become unstable more frequently. Sea level rise during this century produce an increasing erosion rates over soft cliffs. Additionally, higher groundwater level also produces an increase in the number and size of the slope failure. The results represent an important step-forward in linking material properties to the processes of cliff recession and the subsequent long-term response under changing environmental conditions.

A new process–response coastal recession model of soft rock cliffs

The development of cliff erosion predictive models is limited by the complex interactions between environmental processes and material properties over a range of temporal and spatial scales. Current models incorporate a stochastic representation of cliff behavior based on assumptions regarding the magnitude and frequency of events in a probabilistic framework. The new model presented here has been developed to incorporate the behavioral and mechanical characteristics of coastal cliffs which are dominated geologically by overconsolidated clays (tills) and an associated protective colluvial wedge. This model is capable of providing precise and stable responses to some of the inherent uncertainties in cliff recession processes including those caused by different failure mechanisms e.g. colluvium generation, groundwater and erosive tidal cycles. Material strength is incorporated using the unconfined compressive strength of the material that composes the cliff. Unlike previous models, a calibration parameter is restricted to account for uncertainties linked to marine processes. The mechanisms of cliffline retreat have been identified as slump and topple landslides. Once cliff material has fallen, colluvium formation at the cliff foot is incorporated into the model using three different procedures according to the geomechanical characteristics of the debris. The model is validated through profile evolution assessment at various locations of coastline retreat on the Holderness Coast, UK. Higher groundwater content also produces an increase in the number and size of the slope failures. The results represent an important step-forward in linking material properties to the processes of cliff recession.

The effect of coastal defences on cliff top retreat along the Holderness coastline

Summary This study investigates variations in soft cliff retreat and the impact of coastal defences along 55 km of the Holderness coast between 1845 and 2005. The analysis of three approximately 50-year periods (1854–1905, 1905–1952, 1952–2005) gives a retreat rate of between 0.8±0.4 m/yr and 2.1±0.4 m/yr. Retreat varies spatially and temporally due to natural causes and human activity, especially 19 th century beach mining and coastal defence construction. Defences reduce sediment input and modify the sediment budget, usually resulting in a sediment deficit down-drift, leading to the development of a set-back. Using data from historical and modern Ordnance Survey maps, aerial photographs, and Differential Geographical Positioning System (DGPS) surveys, the cliff top was selected as a reference feature. Set-back due to defence construction at Barmston, Hornsea (two periods), Mappleton and Withernsea (two periods) was analysed, giving six different time periods. Short time periods are unreliable due to large mapping uncertainties and natural variability. Two cases showed excess retreat for tens to thousands of metres down-drift over a long time period since defence construction. Two cases were indicative of excess retreat, but require more time to elapse after defence construction (in these cases >20 years) to reach a definitive conclusion. Two cases were inconclusive, but possibly maintained a constant retreat rate post-defence construction. Hence, at the scale of Holderness, defences have changed the pattern of erosion rather than stopping it. Accelerated retreat down-drift of defences can threaten human infrastructure and buildings and reduce the efficiency of defences. This should be recognized in shoreline management planning.

Understanding the recession of the Holderness Coast, east Yorkshire, UK: a new presentation of temporal and spatial patterns

Abstract The Holderness coastline is known to be one of the most rapidly retreating coastal regions in Europe. Previous studies on the recession of this coastline have often concentrated on providing a single annual value for the whole coast or for large subdivisions of it; however, relatively little attention has been given to the overall spatial and temporal variability. This paper summarizes and critically appraises the work previously undertaken in this region, presents the results of the former recession rate investigations and displays new interpretations of the data. This assessment found there to be a knowledge gap relating to the processes involved in the recession of this coastline, particularly with regard to frequency of high recession events, further knowledge of which could assist in the planning of the region. It is concluded that many of the former investigations are inadequate by today9s standards, because of either the methods employed or the manner in which the results are displayed. Significant steps in gathering high-quality data relating to the erosion of this coastline have been made by the East Riding of Yorkshire Council with the initiation of their Erosion Post monitoring scheme and more recently by their dGPS monitoring. However, if further advancement is to be made in the understanding of the erosion of this region, this work will need to be supplemented with geomorphological monitoring of the cliff line, which will further resolve the processes occurring and aid the production of predictive models. These geomorphological data could be obtained through employment of traditional methods as well as new techniques such as laser scanning or digital photogrammetry. Supplementary Material A table giving the magnitude and variability in recession at each Erosion Post location and graphs showing the actual annual variations for each Erosion Post, calculated using a filtered version of the Erosion Post dataset, are available at http://www.geolsoc.org.uk/sup18345.

Hierarchical random effect models for coastal erosion of cliffs in the Holderness coast

Prediction of possible cliff erosion at some future date is fundamental to coastal planning and shoreline management, for example to avoid development in vulnerable areas. Historically, to predict cliff recession rates deterministic methods were used. More recently, recession predictions have been expressed in probabilistic terms. However, to date, only simplistic models have been developed. We consider the cliff erosion along the Holderness Coast. Since 1951 a monitoring program has been started in 118 stations along the coast, providing an invaluable, but often missing, source of information. We build hierarchical random effect models, taking account of the known dynamics of the process and including the missing information.

Using geomorphological rules to classify photogrammetrically-derived digital elevation models

An object-orientated expert system is used to identify beach and cliff landforms from Digital Elevation Models (DEMs) on the basis of topological and morphometric rules. The ord landform of the Holderness coast, north-east England, is interpreted as an indicator of enhanced cliff erosion and consists of various beach, till shore platform and associated steep/stable cliff constituents. Each of these are characterised by expert rules through their topological relationship with other constituents and typical values of height, slope, aspect and convexity. Two DEMs (1996 and 1997) are derived from the application of digital photogrammetry to stereo aerial photography provided from the LOIS (Land-Ocean Interaction Study) project. A rule-based classification of landforms is performed using COAMES (COAstal Management Expert System), producing results that conform to historical ground estimations and which identify zones of intense erosion and their commensurate movement with the ord landform over time. The result is achieved through the intelligent storage and operation of classification techniques, which should facilitate non-specialist usage.

Determination and prediction of sediment yields from recession of the Holderness Coast, NE England

Determination and prediction of sediment yields from recession of the Holderness Coast, NE England

Determination and prediction of sediment yields from recession of the Holderness Coast, NE England

The rapidly eroding cliffs and foreshore of the Holderness Coast represent one of the largest sources of sediment discharging in the southern North Sea. For effective coastal management it is important to understand the sediment sources, transport pathways and depositional sinks. The sediment budget is regarded as one of the key information needs for sustainable planning and management. In order to quantify the sediment yield from recession of the Holderness Coast, digital photogrammetry has been used, together with nearshore bathymetric survey data, to produce a single DTM for a length of over 52 km of coastline. Other data including geological sections, sediment lithology, recession rates and the location of coastal defences have been added to the DTM to create a GIS for the Holderness Coast. The GIS has been used to predict the volume and nature of the sediment yield assuming that historical recession rates continue. The GIS can also be used to predict future yields using assumptions of accelerated recession or the implications of arrested retreat due to construction of defences.

Tide, wave and suspended sediment modelling on an open coast — Holderness

An intensive series of observations off the Holderness coast was followed by a related set of modelling applications. Observations included: aircraft and satellite remote sensing, H.F. and X-band radar, ship surveys and in situ instruments on the sea bed and at the sea surface. These observations aimed to monitor, over three successive winter periods, the dynamics and sediment distributions in the vicinity of this rapidly eroding coastline. Associated modelling applications included components simulating: (i) tides and surge currents; (ii) wave evolution; (iii) vertical distributions of turbulence and SPM (suspended particulate matter) and (iv) resulting spatial patterns of sediment transport in the region. Simulations of tidal currents confirmed the accuracy of such models, given accurate fine-resolution bathymetry and appropriate boundary conditions. New developments of WAM, the spectral wave model required for fine-resolution applications in shallow water (described by Monbaliu et al. [Monbaliu, J., Padilla-Hérnandez, R., Hargreaves, J.C., Carretero Albiach, J.C., Luo, W., Sclavo, M., Günther, H., 2000. The spectral wave model WAM adapted for applications with high spatial resolution. This volume.]) are tested here. A number of additional features pertaining to shallow water are revealed including the sensitivity to specification of wind directions and the excessive temporal spreading of short-lived distant events. Likewise, the application of the generic single-point models for vertical profiles of turbulence and SPM (described by Baumert et al. [Baumert, H., Chapalain, G., Smaoui, H., McManus, J.P., Yagi, H., Regener, M., Sündermann, J., Szilagy, B., 2000. Modelling and numerical simulation of turbulence, waves and suspended sediment for pre-operational use in coastal seas. This volume]), are tested and also shown to be appropriate for simulating localised resuspension of SPM. This simulation also illustrates how, in shallow water (<15 m), tidal and wave dynamics interact with significant mutual adjustments and with first-order influence on stress at the sea bed and thereby erosion and suspension processes. Some preliminary simulations of net sediment movement are included, involving an integration of the above effects. These simulations emphasise how, in all but the shallowest water, the mobility of coarse grain sediments is limited to occasions of extreme waves. By contrast, the movement of fine sediments follows that of the residual tidal current streamlines, i.e., primarily longshore with attendant cross-shore dispersion. However, significant variation between closely-spaced observations indicates the irregularity and complexity of such distributions. It is concluded that because of the inability to prescribe the spatial distribution of available surficial sediments (including size distributions) such simulations can only be expected to reproduce the essential statistical characteristics of SPM concentrations. The availability of extensive remote sensing or in situ data can help to circumvent this problem.