Relict wave formed berms and storm ridges, aeolian formed foredunes, and a mix of these are all termed beach ridges. This paper briefly reviews sand or mixed sand/gravel ridge formation, and then examines whether sea level at the time of formation can be determined from beach ridge height, -crest-swale elevational differences, and the foredune toe-top of backshore boundary. It further examines whether it is possible for sand beach ridges to be currently situated above present sea level yet be formed by lower sea levels. The results indicate that the foredune toe-top of backshore position can be relatively well established from both field surveys and GPR studies and relates well to sea level. Beach ridge height is a highly unreliable indicator of sea level. Claims of terrestrially prominent sand beach ridges formed by lower sea levels appear spurious.

In recent decades, significant anthropogenic impact has modified European coastal dunes, leading to the development of blowouts, a common wind erosional feature. This study investigates a small trough blowout altered by closed human footpath since several decades at Canet-en-Roussillon during both offshore and onshore wind events. Campaigns consisting of 26 2D ultrasonic anemometers deployed at 0.30 m across the entire surface of the blowout. Simultaneously, sediment transport runs were conducted using Hilton sand traps. The results revealed the blowout as a double-nested system with distinct wind dynamics driven by bidirectional wind regimes. Section 1 (landward) is subjected to oblique incident winds, whereas Sect. 2 (seaward) is governed by parallel flow. The interplay between the winds complexity and the morphology of the blowout results in relatively low sediment transport rates. Although offshore winds dominate the environment, it is the onshore winds that generate the highest transport rates. This dynamic raises important questions about the long-term stability and lifespan of such systems.

This study enhances the accuracy of optical satellite-derived bathymetric datasets in a shallow, mixed-bottom, low-wave-energy coastal environment by identifying the optimal combination of input satellite imagery, spectral bands, and empirical derivation techniques. A total of 109 unique derivations were performed based on an exhaustive combination of these variables. These derivations were calibrated and validated using 1,064,536 ground truth observations. The results revealed that the multiband linear technique consistently outperformed the band ratio technique, achieving the best results with input bands from PlanetScope SuperDove imagery. The top-performing derivation attained an R2 value of 0.94 and an RMSE of 0.41 m when compared with the ground truth data, surpassing the published RMSE values in similar environments. Further validation beyond the calibration site confirmed its effectiveness within depths of 0.5 m to 5 m, demonstrating an RMSE of 0.51 m, albeit with a gradual reduction in accuracy with increasing depth. This research not only identifies the optimal combination of variables but also provides valuable insights into how the number of input bands, their spatial resolution, and their specific spectral properties (central wavelength and bandwidth) influence the quality of satellite-derived bathymetry datasets. Challenges remain in accounting for mixed bottom types and their variable albedos.

Accurately estimating sediment transport rates is essential for predicting shoreline changes and guiding coastal management strategies. While existing longshore transport models primarily assume alongshore uniform sandy shorelines, the reality is usually more complex. Many coastal environments exhibit natural features and engineered structures that challenge these models by altering sediment transport and morphodynamic processes. This study presents observations from an extensive field campaign at the Cape Dombey headland in Robe, South Australia, incorporating a co-located acoustic current meter and sediment profiler to examine sediment bypassing during summer and winter. Offshore and nearshore wave characteristics and water levels were measured, with nearshore wave heights ranging from similar to 0.5 m in summer to >2.5 m during winter storms. Statistical analysis revealed wave refraction, diffraction, and breaking over a submerged headland extension as the main drivers for wave transformation around the headland. Three distinct hydrodynamic regimes were identified, characterized by specific current directions and sediment transport rates around the headland. A novel conceptual model for headland bypassing is proposed, describing these regimes and identifying sediment transport patterns over event time scales. Sediment transport rates under swell-dominant (Regime 2) and seadominant (Regime 3) conditions were up to 30 and 40 times higher than during calm conditions (Regime 1). Our conceptual model builds upon existing models by providing a detailed description of headland bypassing mechanisms under various hydrodynamic forcing conditions. This study advances understanding of sediment transport around headlands in high-energy environments and provides an adaptable framework for measuring and analyzing headland bypassing in other coastal settings.

Understanding and being able to model nearshore sediment transport processes is important for the development of coastal protection and management strategies. To date, most formulations for longshore sediment transport and associated shoreline change have been developed for idealized alongshore uniform sandy beaches. However, many coastlines are far more complex, such as those featuring headlands, which may considerably alter longshore transport processes (Ab Razak, 2015). Headlands can (partially) obstruct longshore transport, thus affecting the sediment balance and, as a result, complicate predictions of shoreline change compared to the case of an alongshore uniform beach. Quantitative expressions to estimate sediment bypass rates around headlands are rare (McCarroll, 2021), especially for large headlands with complex shape. This is primarily due to substantial spatio- temporal variations in sediment transport that can occur in such complex environments and the difficulty of conducting field measurements in high-energy headland environments (McCarroll, 2018), which are critical for developing and validating (empirical) sediment transport formulas. This study adopts a novel field set-up to explore headland bypassing in the high-energy environment around Robe, South Australia, by measuring sediment concentrations and flow velocities around a large and complex headland. The field data is then used to validate a numerical model.

This study examined a sediment plume from Australia’s largest river, The River Murray, which was produced during a major flood event in 2022–2023. This flood resulted from successive La Niña events, causing high rainfall across the Murray–Darling Basin and ultimately leading to a significant riverine flow through South Australia. The flood was characterised by a significant increase in riverine discharge rates, reaching a peak of 1305 m³/s through the Lower Lakes barrage system from November 2022 to February 2023. The water quality anomaly within the coastal region (<~150 km offshore) was effectively quantified and mapped utilising the diffuse attenuation coefficient at 490 nm (Kd490) from products derived from MODIS Aqua Ocean Color satellite imagery. The sediment plume expanded and intensified alongside the increased riverine discharge rates, which reached a maximum spatial extent of 13,681 km2. The plume typically pooled near the river’s mouth within the northern corner of Long Bay, before migrating persistently westward around the Fleurieu Peninsula through Backstairs Passage into Gulf St Vincent, occasionally exhibiting brief eastward migration periods. The plume gradually subsided by late March 2023, several weeks after riverine discharge rates returned to pre-flood levels, indicating a lag in attenuation. The assessment of the relationship and accuracy between the Kd490 product and the surface-most in situ turbidity, measured using conductivity, temperature, and depth (CTD) casts, revealed a robust positive linear correlation (R2 = 0.85) during a period of high riverine discharge, despite temporal and spatial discrepancies between the two datasets. The riverine discharge emerged as an important factor controlling the spatial extent and intensities of the surface sediment plume, while surface winds also exerted an influence, particularly during higher wind velocity events, as part of a broader interplay with other drivers.

Foredune morphology can be influenced or controlled by multiple natural factors including sediment supply, wind regime, vegetation cover and distribution, species presence/absence, plant morphology, surfzone-beach type, wave erosion and storm frequency and magnitude, and barrier dynamics (e.g. prograded, aggraded, or retrograded barrier types). The role of climate in controlling foredune type and morphology, as well as foredune mode (continuous ridges, discontinuous ridges or nebkha) has been poorly investigated to date. This paper examines the role of climate, and, in particular, rainfall, in controlling vegetation cover, and foredune type and mode. In general, as rainfall declines the vegetation percent cover declines, tree species disappear, and foredunes tend to be less and less regular symmetrical ridges and more discontinuous foredune/blowout complexes. As annual rainfall falls below similar to 300 mm, nebkhas become more common and eventually only nebkhas can form in arid coastal environments. Multiple examples of foredune types and modes in various climate settings are examined to show that climate, and especially rainfall is indeed a major driver of foredune type and mode. However, shoreline progradation rate or shoreline stability may exert an influence especially where the shoreline has been stable for a long period of time.

Many coastal dunes are experiencing human stabilization by fencing, vegetation planting or reshaping the dune profile, resulting in a modification of air flow and sediment transport patterns. For example, a taller and steeper dune may result in an increased zone of wind flow separation and deceleration, resulting in the reversal of flow and sediment transport to the dune toe from the backshore during offshore winds. (Walker and Nickling, 2002; Hesp and Smyth, 2019). Globally, the pattern of reversed or deflected flow plays a key role in dune evolution, particularly when an offshore wind regime is dominant (Bauer et al., 2012; Nordstrom and Jackson, 2018). Recently, Computational Fluid Dynamics (CFD) has given new insights to complex flow recirculation on the lee-side of heavily managed coastal dunes on developed coasts during onshore winds (Smyth and Hesp, 2015; Nguyen et al., 2022). This research is the first to investigate wind flow and sediment transport dynamics on a anthropogenically constructed dune in offshore wind conditions. CFD simulations were completed for three offshore wind directions over a computational domain constructed from a 3D topographic LiDAR surface. Simulations were validated by a comparison with wind

This study investigates the impact of Hurricane Fiona on sandy beaches and foredunes within Prince Edward Island National Park (PEINP). Fiona was the strongest storm to strike the island in nearly a century, with significant wave heights reaching 8 metres. Its impact on sandy beach-dune systems provides an opportunity to gauge the effectiveness of current PEINP's management policies and practices, and to consider potential changes that enhance the role of foredunes and beaches as natural defences against future storms and rise in relative sea level. Survey data and ground/UAV photography were used to compare various locations before (October 2021 to July 2022) and after (October 2022 and May 2023) the storm. High dunes experienced stoss slope erosion without significant changes in the height or position of the foredune crest, offering protection to landward areas. Low dunes were substantially eroded, leading to overwash in certain areas, and dunes located on bedrock and till were completely eroded, exposing the underlying surface. Hurricane Fiona's impact highlights the need of reinforcing current management strategies in PEINP that aim at safeguarding the natural biotic and abiotic components of beach-dune systems, and securing the accommodation space needed for their natural inland migration with rising sea level.

1 Ocean shores are among the most spectacular and sought-after sites for leisure activities, including ‘nature and wilderness experiences’. Some of these activities can involve the use of off-road vehicles (ORVs) driven across extensive stretches of sandy coastlines. Yet, this recreation mode can be controversial because of environmental, cultural, social, and ethical concerns. However, ORV users often question the putative impacts, especially the ecological aspects. 2 Here, we review the available published data about the ecological impacts of vehicles on coastal plants. We focus on vegetation because of its critical role in coastal resilience and its foundational role in the structure and function of dune-beach systems. The principal type of evidence is a formal meta-analysis of effect sizes that can be unambiguously linked to ORV use. 3 The evidence of serious ecological harm caused by ORVs to plants of beach-dune habitats is geographically widespread, extensive in taxonomic coverage (253 species, 174 genera, and 64 families), sizeable in the magnitude of reported impacts (443 records) and statistically robust (significant negative departures from zero responses). 4 Vegetation stressed by ORVs typically has substantially reduced abundance, cover, biomass, area, occurrence, diversity, and productivity. ORVs also significantly alter the composition and structure of assemblages. 5 Degradation occurs rapidly, with the first few vehicle passes causing most of the damage. Thresholds of impact can be exceptionally low (one or two cars separated by weeks), implying that in many cases, dunes and the back-shore of beaches have extremely limited resilience to repeat traffic by off-road vehicles: No ‘safe threshold’ of use may exist. 6 Recovery after closure to off-road vehicles is highly variable, depending on species traits (slower for woody shrubs) and habitat conditions (slower for back-dunes). It can be protracted, with some assemblages typically taking around a decade or more to recover. 7 The exceptionally low tolerance of many coastal plant species and habitats translates into policies to phase out ORV use on ocean shores and dunes. Spatial closures and strict controls should be the mainstay of management interventions, supplemented by novel approaches seeking to identify where and when environmentally safe and benign practices may exist and whether these can be culturally and ethically acceptable.

Many drivers are responsible for dunefield morphology and changes from mobile to stable states, with surface and subsurface records potentially registering past drivers acting on dunes. Phases of aeolian transgressive sand sheets (TSS) are recorded in an extensive stretch of the Holocene barrier of the southernmost coast of Brazil from the millennial to modern ages. Ancient phases of TSS are evident in the modern transgressive dunefield (TDf) of the Concheiros Barrier, marked by vegetated, crenulate low precipitation ridges. In this work, we examined surface and subsurface records of aeolian deposits, exploring possible past climate conditions that led to the formation of these features. A 1000 m-long Ground Penetrating Radar (GPR) cross-section was conducted to determine whether these aeolian morphologies are observed in the stratigraphic subsurface record. Optical Stimulated Luminescence (OSL) dates were taken from vegetated relict TSS phases on the coastal barrier. The GPR section identified a single radarfacies, interpreted as a TSS. A few TSS units could be individually recognized, indicating overlapping low precipitation ridges/TSS margins. OSL dating indicated aeolian activity at 30 + 3 years (P01), 1244 + 123 years (P02), and 1464 years + 130 years (P03). The youngest age is correlated with sand mobilization from AD 1996-2000, as described by previous studies. This phase was induced by climate conditions and it was caused by decreased vegetation cover, lower rainfall and water tables, and increased wind velocity and aeolian drift potential. The episodes of TSS mobilization at 1244 (+123) and 1464 (+130) years ago may have been caused by either drier conditions or intensified wind regimes, as noticed in different parts of southern Brazil by other studies. These drivers likely have been shaping the Holocene barrier geomorphology at the Concheiros Barrier for over 1400 years, considering the ancient phases of TSS formation in the subsurface stratigraphic record.

The past efficacy and future viability of sand recycling is evaluated for Adelaide’s beaches in South-Australia, making use of the one-line numerical model, ‘ShorelineS’. A wide variety of measures were introduced here in the last decades, such as (offshore) breakwaters, groynes, revetments and sand nourishments including regular sand recycling using both a pipeline and regular sand carting. Satellite derived shoreline change rates are used to verify modelled rates deduced from the one-line model wherein management and coastal structures were incorporated. The management is then removed from the model simulation to determine the underlying shoreline change rates. The results of these simulation scenarios provide insight into the system and historic performance of management practice. In addition, an investigation into the future viability of sand recycling as a primary management strategy is investigated using a dynamic nourishment application tool.

Blowouts play a critical role in reactivating coastal dunes by serving as sand transport corridors. While extensive studies have explored aeolian processes within blowouts under onshore and oblique wind regimes, less attention has been given to environments dominated by opposing wind directions. The Canet-en-Roussillon coastal dune (SE France) is subjected to both offshore and onshore winds, with a main blowout (B2) exhibiting a complex morphology altered by human foot traffic. This blowout was instrumented (anemometers, sediment sand traps, topographic surveys) during both offshore and onshore wind events. The study demonstrates that onshore winds, though less frequent, are the dominant morphogenic force, driving rapid landward elongation of the blowout. Multi-year analyses reveal that this elongation has facilitated the connection with a closed footpath, resulting in its elbow-shaped morphology. At event timescales, offshore winds induce minimal sediment transport due to vegetated fetch surfaces, while onshore winds promote significant sand transport and topographic variability via a bare sand fetch. Sand availability emerges as a critical factor modulating blowout evolution. The dual wind regime interacts with anthropogenic disturbances, sustaining the current morphology. Offshore winds transport sediment seaward, while the bifurcation of onshore winds by the footpath creates an internal accumulation zone, inhibiting depositional lobe formation and further elongation. These findings challenge the traditional understanding of blowouts as unidirectional sand transport corridors in dual wind environments and highlight the role of anthropogenic influences on their morphology. Further research is needed to determine whether these mechanisms are consistent across larger blowouts with higher sand volumes.

Coastal dunes result from complex interactions between sand transport, topography and vegetation. However, uncertainty still persists due to limited quantitative analyses, integrating plant distribution and morphologic changes. This study aims to assess the initiation and maintenance of feedback processes by analysing the early development stages of incipient foredunes, combining data on the evolution of the plant cover and communities and dune morphology. Over three years, the monitoring of a newly formed dune (1 ha plot) reveals the progressive plant colonisation and the episodic accumulation of sand around vegetated areas controlled by sediment availability. Distinct colonisation rates were observed, influenced by inherited marine conditions, namely topography and presence of beach wrack. Berm-ridges provided elevations above the critical threshold for plant colonisation and surface roughness, aiding sediment accumulation. Beach wrack above this threshold led to rapid expansion and higher plant concentration. In the initial stages, vegetation cover significantly influenced sediment accumulation patterns, with higher accumulation around areas with high plant cover and low slopes or around areas with sparse vegetation but milder slopes. As the dune system matured and complexity grew, the link between vegetation cover and accumulation became nonlinear. Mid to low coverages (5-30 %) retained most of the observed accumulation, especially when coupled with steep slopes, resulting from positive feedbacks between vegetation, topography and sand transport. As foredune developed, vegetation cover and diversity increased while inherited morphologies grew vertically, explaining the emergence of dune ridge morphological types. Flat surfaces lacking wrack materials experienced a three-year delay in colonisation and sand accumulation, leading to the formation of terrace-type incipient foredunes. These observations underline feedback processes during the early stages of dune formation, with physical feedbacks primarily driving initiation and biophysical feedbacks prevailing in subsequent colonisation stages.

Dunes form where winds blow over a bed of mobile sediment grains – conditions that are common in our solar system. On Earth, dunes abound in arid continental interiors and along sandy coastlines. Dune fields have also been recognized on Venus, Mars, Saturn's moon Titan, and Pluto. In response to the different boundary conditions and other environmental forcings, dunes adopt a rich diversity of shapes, sizes, and behaviors. Thus, people around the globe and over centuries have developed a rich vocabulary to describe dunes and their complexity. As a result, existing dune nomenclature often includes redundant terms with differing definitions across scientific communities. Previous studies have endeavored to link dune shape to environmental forcing, usually by means of correlation. Although instructive, correlation-based classifications can be misleading if not based on an underlying mechanics and if dune morphogenetic classes are not uniquely defined. Here, we synthesize existing dune terminology and use the last two decades of research on dune morphodynamics to propose three complementary dune classification schemes based on: (1) descriptive dune gemorphology, (2) morphodynamic processes, and (3) fluid mechanics and physics of sediment transport. The first classification relates dune types to geomorphic setting, presence or absence of vegetation or obstacles, and dune shape (including planform shape, and cross-sectional symmetry or asymmetry). Dune classes can be further subdivided where the direction of sand transport is known independently. The second classification relates dune types and shapes to bed properties (sand-covered vs partially starved bed) and wind forcing (directional variability or the relative strengths and directions of wind modes) that together influence dune dynamics (growth, migration, elongation) and select the dominant processes by which dunes are shaped and oriented relative to the resultant transport direction. The third classification relates, for different planetary environments, the range of possible dune sizes, from minimum to maximum wavelength, to flow regime (rough or smooth) and response of sediment transport, which influence the coupling between sand bed topography, fluid flow, and sediment transport. These characteristic lengths are useful scales for comparative geomorphology. The three classification schemes provide complementary information. Together, they form a unified framework for geomorphologists, sedimentologists, geographers, physicists, and others to describe windblown sand dunes on Earth and beyond through their shape, dynamics, and size as a response to winds and boundary conditions.

The bimodal wave climate of the semi-protected shallow Gulf St Vincent in South Australia has been analyzed through a forty-year (1980-2020) wave hindcast and an investigation into the climatic drivers of wave climate anomalies is presented. The sea and swell partitions of the wave climate were modelled independently as well as using an integrated model with both partitions represented. The wave hindcast was validated against two wave buoys located off the coast of Adelaide’s metropolitan beaches and key wave parameter anomalies were calculated across the gulf. Teleconnections were investigated, and the Southern Annular Mode is found to have the strongest correlations to wave parameter anomalies while the Southern Oscillation Index and the Dipole Mode Index fluctuations are found to correlate seasonally with wave parameter anomalies. Projected future trends of these climate drivers from literature have been related to the teleconnections found in this study to inform future trends of bimodal wave conditions in the gulf. The Southern Annular Mode is projected to trend positive which will reduce wave height and the westerly component of waves in the gulf, while the Southern Oscillation Index is projected to become more variable in the future which will lead to more extreme winter and spring wave conditions. An understanding of these trends allows coastal managers to pre-emptively manage the impacts of waves on the coastline at a seasonal to annual basis and provides insight into future wave conditions beyond these time periods.

Foredunes provide many environmental and ecosystem services including protection from wave erosion and flooding hazards during storm events. While the impact of human interventions on the short-term evolution of coastal dunes is reasonably well understood, less is known about their contemporary influence on current wind and sediment dynamics several decades after implementation. The coastal dunes in Leucate (SE, France) have been anthropogenically constructed and are dominated by offshore wind conditions. Since their construction 20 years ago, a distinct variation in their longshore morphology has developed that is inherited from its original construction. The northern part of the dune has a symmetrical profile with a 28 degrees degree stoss slope, 30 degrees lee slope and a single crest. The southern part is asymmetric, with a gentler stoss slope (12 degrees ), 26 degrees lee slope, and a double crest. To explore the potential geomorphic impacts of this distinct difference in morphology, several numerical simulations with varying wind speeds and direction were conducted. We used Computational Fluid Dynamics (CFD) to explore the spatial variations of the near surface wind flow, shear stress and aeolian sediment transport. Results: show that for each scenario, near surface wind speed accelerated toward the dune crest on the windward slope of the dune. The maximum wind speed varied with incident wind direction, the highest speeds occurring when incident wind flow was perpendicular to the dune crest. The double crest in the southern section of the dune affected the wind flow by inducing two consecutive speeds-up zones, with a greater maximum wind speed than on the single crested dune. Wind flow separation was observed where a steep lee slope was present (single crested dune), and only during perpendicular winds. This suggests that the shape of the dune and the direction of the wind are key parameters rather than wind speed. The area affected by reversed separated flow was spatially limited and did not extend beyond the dune toe but was below the threshold for aeolian sediment transport. Elsewhere in the lee of the dune, the wind was only deflected by an order of 15 degrees for the oblique winds (310 and 330 degrees ), and less than 10 degrees for the perpendicular wind (290 degrees ) on the southern part. In these locations, the shear velocity exceeded the threshold, notably on the southern dune, which coincided with the formation of undulating aeolian deposits in the lee of vegetation on the dune crest. The spatial differences observed in wind flow and aeolian sediment transport processes on this human-made dune were directly inherited from differences in their construction two decades ago. These results demonstrate the importance of the constructed dune profile, due to its potential impact on the long -term evolution of the landscape and the sediment budget of the system.

The essence of stories of human-environment interactions can be preserved in oral contexts for millennia, creating novel opportunities for humanizing the past. This study examines stories (knowledge-rich narratives) about the ancestral being Ngurunderi, told by Ngarrindjeri peoples of South Australia. Three elements of the Ngurunderi narrative are considered. The first recalls his journey along a 170-km long coastal barrier (Younghusband Peninsula) when this was continuous. The second discusses Ngurunderi's encounters with what are now islands off the Fleurieu Peninsula, some of which he created, interpreted as memories of when sea level was lower and "islands" were contiguous with the mainland. The third refers to the crossing of a land connection between modern Kangaroo Island and the Fleurieu Peninsula, later submerged to form Backstairs Passage. Using paleogeographic data, the most recent times at which each narrative element could have taken place and observed by people are estimated. This research suggests that: (1) stories about Younghusband Peninsula may be >6700 years cal BP; (2) islands off the Fleurieu Peninsula were created 6800-10,400 cal BP; and (3) submergence of Backstairs Passage occurred 11,000-10,100 cal BP. Narratives are linked to the period of early Holocene sea-level rise, the rapid 8200-cal BP sea-level rise event, and stabilization of sea level 7000-6000 cal BP. These narratives humanize the past and provide information that can be interpreted as both observed coastal and seascape changes as well as past human responses to rising sea level that can inform our future encounters with coastal-landscape change.

The Younghusband Peninsula coastal barrier extends -190 km and is predominantly comprised of a mix of active, semi-stabilised and stabilised (relict) transgressive and parabolic dunefields. Wave driven shoreline erosion has triggered the rapid development of a transgressive dunefield along a portion the peninsula. This study focuses on a -2 km region with the highest regional erosion rates (> -2.0 m/year since 1988), and which has experienced rapid destabilisation and subsequent landward translation of the dunefield. Aerial LIDAR derived datasets of the barrier system from 2008 and 2018 and eight drone photogrammetry surveys between August 2020 and April 2022 are used to compare the rates of change across the beach-dune system. The net and intra-survey changes are used to show the short- to medium -term system response and illustrate the relationship of sediment dynamics to the developing morphology and structure of the dunefield. Shoreline change rates (m/ yr) are sourced from the Digital Earth Australia coastlines dataset which provides annual rates for continental Australia from a Landsat time series (1988-2021). When the rate of shoreline change is segmented from the total dataset to the study time-period (2008-2021), the average resulting rates show an increase from -2.2 m/yr to -3.3 m/yr, respectively. This coincides with a landward advance rate of >10 m/yr from 2008 of the dunefield edge, with the fastest eroding dune toes corresponding to regions with the highest rate of dunefield translation and transgression. Net volumetric totals and their ratios of gain to loss of sediments show that significant sediment is lost to offshore during the retrogradation of the dunefield as only a fraction of the stoss slope sediment is transferred landwards. All regions of the dunefield exhibit a net loss of sediments but the hightemporal resolution shows that the magnitude of 3D changes varies through time. An adapted model of erosional stoss slope evolution and dunefield development is advanced and a temporal model of transgressive dunefield evolution is synthesised.