Coastal Morphology Research Articles

Shoreline Prediction Modelling as a Base Tool for Coastal Management: The Catania Plain Case Study (Italy)

Coastal dynamic is the complex result of multiple natural and human processes, and past and future coastal behavior studies become fundamental to support coastal zone management. However, the reliability of coastal evolution studies is strongly dependent on the analyzed time interval. The longer the period is, the more reliable the past shoreline change analysis and the forecast of shoreline position will be. The present study showed the 50-years shoreline evolution of the Catania coastal plain (Southern Italy), a densely populated area where human-induced processes profoundly changed natural dynamics. Landsat and Sentinel imageries were used to extract shorelines’ position over the time between 1972 and 2022 and the DSAS tool was used to calculate the shoreline change rates. The shoreline evolution in 2032 and 2042 was performed by the Kalman filter method, a tool largely applied to forecast short-term shoreline future position. Most of the Catania coastal plain was mainly retreating over the last decades. However, the most significant changes were registered in correspondence with the coastal structures and the river deltas. The reliability of the forecasting model was highly related to the coastal morphology. As such, the lower RMSE values were calculated in correspondence with the uniform coastal subsectors.

A BEM-Based Model of a Horizontal Axis Tidal Turbine in the 3D Shallow Water Code SHYFEM

We present a novel 3D implementation of a horizontal axis tidal turbine (HATT) in the shallow water hydrostatic code SHYFEM. The uniqueness of this work involves the blade element momentum (BEM) approach: the turbine is parameterized by applying momentum sink terms in the x and y momentum equations. In this way, the turbine performance is the result of both the flow conditions and the turbine’s geometric characteristics. For these reasons, the model is suitable for farm-layout studies, since it is able to predict the realistic behavior of every turbine in a farm, considering the surrounding flow field. Moreover, the use of a shallow water code, able to reproduce coastal morphology, bathymetry wind, and tide effects, allows for studying turbine farms in realistic environments.

Coastal Vulnerability at West Pasaman Regency

West Pasaman has rich coastal potency. Marine resources and coastal tourism become income source for this regency. Besides the potency, West Pasaman Coast also vulnerable because it lays on tectonic path subduction and bordered with Hindia Ocean that triger abration, earthquake and tsunamis. The combinations of high abration and flat coast with mud and sand make the West Pasaman Coast very vulnerable. Extreme weather and dense population with convensional living in the coastal area create the complexity of coastal problems. Early, The Coastal Vulnerability Index (CVI) is a method to analyze coastal vulnerability based on certain factors i.e ocean hydrodinamics and coastal morphology. But nowadays, to minimize the risk of natural disasters, the CVI has been modified with additional factors. This research aims to analyze the coast vulnerability of West Pasaman Coast using Coastal Vulnerability Index (CVI) method based on GIS. The study use primary and secondary data. The field survey was conducted on April 2019 with purposive sampling method at 6 districts and 10 sites as the observation points. Those districts are Sungai Beremas, Koto Balingka, Sungai Aur, Sasak Ranah Pasisir, Luhak Nan Duo and Kinali. The result shows that Kinali Coast is categorized as high vulnerability (CVI 3.95) and other 5 districts are moderate vulnerability (CVI 2.3-2.9).

On simulating shoreline evolution using a hybrid 2D/one-line model

Hybrid 2D/one-line shoreline models are becoming increasingly applied over the mesoscale (10 1 –10 2 years; 10 1 –10 2 km) to inform coastal management. These models typically apply the one-line theory to simulate changes in shoreline morphology based on littoral drift gradients calculated from a 2DH coupled wave, flow, and sediment transport model. However, the key boundary conditions needed to effectively apply hybrid 2D/one-line models and their applicability beyond simple planform morphologies are uncertain, which can potentially comprise coastal management decisions. To address these uncertainties, an extensive numerical modelling campaign is carried out to both assess the sensitivity and calibrate an advanced hybrid 2D/one-line model (MIKE21) against six variables in three different sandy coastal system morphologies: (a) a simple planform morphology with a gentle sloping profile, (b) a simple planform morphology with a steep sloping profile, and (c) a complex planform morphology. The six variables considered include nearshore discretisation, bathymetry, bed friction, sand grain diameter, sand porosity, sediment grading, and the weir coefficient of hard defence structures. Five key conclusions are derived from the sensitivity testing and calibration results. First , the optimal boundary conditions for modelling shoreline evolution vary according to coastal geomorphology and processes. Second , specifying boundary conditions within physically realistic ranges does not guarantee reliable shoreline evolution predictions. Third , nearshore discretisation should be treated as a typical calibration parameter as (a) the finest discretisation does not guarantee the most accurate predictions, and (b) defining a discretisation based on process length scales also does not guarantee reliable predictions. Fourth , hybrid 2D/one-line models are not valid for application in complex planform morphologies plausibly because of the one-line theory assumption of a spatially invariable closure depth. Fifth , hybrid 2D/one-line models have limited applicability in simple planform morphologies where the active beach profile is subject to direct human modification, plausibly due to the one-line theory assumption of a constant time-averaged coastal profile form. These findings provide key theoretical insights into the drivers of shoreline evolution in sandy coastal systems, which have practical implications for refining the continued application of shoreline evolution models. • The hybrid 2D/one-line shoreline modelling approach is tested in three coastal morphologies. • Optimal boundary conditions correspond to observed coastal morphology. • The nearshore discretisation in shoreline models should be treated as a calibration parameter. • The hybrid 2D/one-line shoreline modelling approach is limited to simple planform morphologies.

A palynological record of mangrove biogeography, coastal geomorphological change, and prehistoric human activities from Cedar Keys, Florida, U.S.A.

Under the continuous warming trend in the 21st century, mangroves are likely to migrate into more temperate regions in North and South America. However, the biogeography of different mangrove species is still unclear, especially near their latitudinal range limits in the two continents. This study utilizes palynological, geochemical, and sedimentological analyses to record changes in the coastal morphology and vegetation during the Holocene in Cedar Keys, Florida, the mangrove sub-range limit in North America. The multi-proxy dataset indicates that the milder winters during the Medieval Climate Anomaly likely facilitated the establishment of mangroves in the study region, where Avicennia, Laguncularia, and Rhizophora were established in the ~12th (790–850 cal yr BP), ~14th (580–660 cal yr BP), and ~ 16th century (440–460 cal yr BP), respectively. Thus, the Medieval Climate Anomaly likely triggered the poleward mangrove migration in North and South America synchronously. Moreover, the multi-proxy dataset also documents the obliteration of the Woodland Culture near Cedar Keys, where a once-thriving native civilization on Seahorse Key was driven out by the European colonizers, who settled on the mainland and Atsena Otie Key. Over time, the relict sites of the Woodland people on Seahorse Key were covered by mangroves and marsh vegetation since the ~16th century. Overall, our dataset suggests that industrial-era warming may have intensified the poleward mangrove expansion, although this trend had started earlier during the Medieval Climate Anomaly.

Meteotsunamis in the northern Baltic Sea and their relation to synoptic patterns

Low-tidal coastal regions, such as the Baltic Sea, are known to be particularly vulnerable to exceptional high-frequency sea level oscillations such as meteotsunamis. Possibilities of studying sub-hourly sea level variations have recently improved, owing to advancement in temporal resolution of tide gauge observations. In this work, we study high-frequency (period <6 h) sea level oscillations – strongest of which we consider to be meteotsunamis – on the coast of Finland, in the northern Baltic Sea, using quality-checked 1-min observations collected between 2004 and 2015 at 13 tide gauge stations. The intensity of the oscillations varies substantially between stations due to local coastal morphologies. The most intense oscillations predominantly occur in late summer and autumn, although the seasonality may differ between sub-regions. Measured atmospheric data and reanalysis products related to the strongest events reveal two distinct types of atmospheric processes and governing synoptic patterns that are mostly associated with warmer and colder period of year. Consequently, meteotsunamis are classified as summer-type or winter-type events. Most of the summer-type events are caused by surface atmospheric pressure jumps associated with mesoscale convective systems, which are advancing northward over the sea and are embedded into a mid-troposphere jet overtopping an inflow of warm low-troposphere air. At the surface, weak air pressure gradients due to a high-pressure area to the east and a low-pressure area to the west of the Baltic are usually found during summer-type events. The winter-type events, on the contrary, are mostly related to cold fronts and strong northerly-northwesterly-westerly winds at the surface layer. Contrary to summer-type events, surface atmospheric pressure jumps are not necessarily detected during the strongest winter-type events. Deep lows and extratropical cyclones are commonly centered to the north of the Baltic Sea and, at the mid-troposphere level, there is a pronounced westerly jet stream. A hypothesis about the generation mechanism of intense high-frequency sea level oscillations is given: Proudman resonance appears to be the main driver of summer-type events, whereas the main driver of winter-type events is less clear.

Dispersal and coastal geomorphology limit potential for mangrove range expansion under climate change

Abstract Latitudinal range limits for mangroves on high‐energy, wave‐dominated coasts are controlled by geomorphological features and estuarine dynamics. Mangroves reach a southern global range limit along the South African coastline, but the distribution is patchy, with stands occurring in only 16% of the estuaries in the region. Yet, the persistence of forests planted &gt;50 years ago beyond the natural distribution limit suggests that additional estuaries could support mangroves. Understanding regional drivers is necessary to inform global‐scale estimates for how this important ecosystem is predicted to respond to climate change. Here, we combine species distribution modelling (MaxEnt), Lagrangian particle tracking using an eddy‐ and tide‐resolving numerical ocean model, and connectivity matrices, to identify suitable mangrove habitats along the South African coastline at present, as well as under the IPCC RCP4.5 and RCP8.5 climate scenarios. Within the current South African distribution range (±900 km), eight more estuaries were identified to be suitable under contemporary conditions. When considering potential range extension (±110 km), an additional 14 suitable estuaries were identified. Connectivity matrices suggest limited long‐distance dispersal, stranding mostly at or near the release location, and a decreased probability of connectivity towards the range limit. Under both future climate scenarios, 30% of estuaries currently supporting mangroves are predicted to become unsuitable, while an additional six estuaries beyond the current distribution are predicted to become suitable. However, there is limited connectivity between these new sites and established forests. Synthesis. This study shows that dispersal substantially limits mangrove distribution at the southern African range limit and highlights the importance of including this process in species distribution models. Ultimately, our results provide new insight into mangrove conservation and management at range limits that are not controlled predominantly by temperature, as it has been assumed that mangroves will largely expand to higher latitudes under climate change.

Tidal dynamics drive ooid formation in the Capricorn Channel since the Last Glacial Maximum

Relative sea-level changes can dramatically alter coastal geomorphology and coastlines, which, in turn, can fundamentally alter tidal regimes. The Great Barrier Reef (GBR) has undergone around 120 m of relative sea level (RSL) rise since the Last Glacial Maximum, ∼20,000 years ago (ka). Ooid grains (sand sized carbonate sediment) that formed in shallow water (>5 m depth) and under prolonged hydrodynamics forcing are now found at depth ranging between 100 and 120 m under the present day GBR Gulf of Capricorn. The apparent inconsistency between preferential conditions for their formation and the actual environment where they are found at present-day could be used to infer past regional hydrodynamic conditions. Here, we focus on the regional changes in the GBR tidal dynamics over the last 16.8 ka to show that sea-level rise on the GBR has caused significant changes on tidal patterns and dynamics. To do so, we used the first multi-scale palaeo-tidal finite element coastal tidal model of the GBR over five time slices (present day, ∼10 ka, ∼12 ka, ∼15 ka and 16.8 ka), representing the position of RSL at 0 m, 20 m, 45 m, 75 m and 96 m below present. We show that favourable conditions for ooid formation only existed for a short period of time between 16.8 and 11 ka. At that time, the Gulf of Capricorn was a wide shallow shelf with strong currents constantly agitating grains, providing rapid burial, exposure and re-burial cycles. We show that these conditions only existed for a short period of time and hence explain the presence of ooid grain formation in the GBR at that time. We propose ooids formed within the Capricorn Channel at a time of lower RSL than expected and then underwent sub-tidal transportation to their final deposition place via tidal currents, explaining the inconsistency with their age and the depth at which they were found.

Local Tide and Geoid Corrections Significantly Improve Coastal Retracked Jason Sea Surface Heights in the Philippines

Retracking algorithms increase the accuracy of coastal sea surface height (SSH) measurements. However, it is still important to validate these retracking estimates with tide gauge (SSHtg) observations. We downloaded the freely available Jason altimeter SSH processed using the XTRACK-ALES algorithm, then detided the SSH using different tide models. The first model is the default tidal correction based on Finite Element Solution 2014 (SSHfes), and the second model is the T_Tide harmonic analysis of the nearest tide gauge (SSHaltimeter). SSHfes showed a very poor correlation (&lt; 0.31) and very high root mean square error (RMSE, &gt; 29 cm). In contrast, SSHaltimeter generally showed a very high correlation (&gt; 0.91) and low RMSE (&lt; 17.4 cm). A further quality check based on the average and standard deviation of the difference between the SSH readings (SSHfes – SSHtg and SSHaltimeter – SSHtg) also showed the superior performance of SSHaltimeter, which scored &lt; 9.3 and &lt; 16.5 cm, respectively; compared to SSHfes, which scored &lt; 9.3 cm and &gt; 27 cm for the same parameters. The poor performance from the SSHfes likely comes from the complex bathymetry and coastal geomorphology of the country, which is not accounted for in the FES. The Philippines generally has a narrow shelf, and the FES tide corrections may be related to deep-water tides rather than the shallow-water tides observed from tide gauges. Despite the high correlation and agreement between the SSHaltimeter and SSHtg, the rate of sea level rise from the SSHaltimeter in some sites is more than twice the rate from SSHtg, which indicates the possible influence of the vertical land movement.

Adaptation of the SANTOSS transport formula for 3D nearshore models: Application to cross-shore sandbar migration

The ability to model bar migration in the nearshore zone is critically important for predicting coastal morphology. We present a cost-effective wave-averaged 3D model (CROCO) with parameterization of wave-related bedload transport (adapted SANTOSS), and evaluate/calibrate its performance in comparison with data measured in a two-dimensional wave channel. In this model, suspended-load transport (both in and above the wave bottom boundary layer) is resolved by the flow model. We assume that if the tuning parameters are not robust to varying forcing conditions, the parameterization can be considered a failure. The present work is therefore a first step towards a numerical model capable of predicting the onshore and offshore migration of a sandbar under storm and post-storm conditions using the same set of parameters. One way to achieve this goal is to treat the effects of waves and currents in separate formulations to avoid conflicts and redundancy. We show that the implementation and adaptation of SANTOSS in CROCO can achieve this goal, provided that the hydrodynamics are accurately reproduced and the separation between the wave-related bedload and current-related suspended load formulations is respected.

Pier‐Based Measurements of Air‐Sea Momentum Fluxes Over Shoaling Waves During DUNEX

AbstractOpen‐ocean homogeneity is violated in the near shore region by wave shoaling and breaking, varying wind‐swell incidence angles, complex currents patterns, rapid bathymetric changes, and shore‐side topographic features. Consequently, existing drag coefficient parameterizations, which were largely developed in deep water, are not effective. This has an adverse impact on marine forecasts, weather and climate models, and coastal morphology prediction. There exists a critical need to identify and systematically quantify the impact of coastal processes and features on the momentum flux over a wide range of wind speeds. As part of the DUring Nearshore Event eXperiment at the Field Research Facility in Duck, NC, six months of direct flux observations were collected from a tower at the end of a 560 m pier. These were used to study the variability of the aerodynamic drag coefficient. Results show that for winds above 3 m s−1 the drag coefficient was between 15% and 50% higher for onshore winds when compared to alongshore. This is attributed to more energy in the downwind component of the flux around the dominant wave frequency for onshore winds, and is independent of wind speed. Holistically, the Coupled Ocean Atmosphere Response Experiment (COARE) algorithm over predicts the drag coefficient for shoaling waves. When separated by wind direction, COARE best predicts the drag coefficient for onshore winds. The results of this study can help the development of more robust nearshore momentum flux parameterizations. This will ultimately lead to improved weather and climate forecasting in the littoral zone, and more physically realistic short‐ and long‐term coastal resilience strategies.

Testing the equations for wave attenuation over shore platforms

Modelling the geomorphologic evolution of rocky coasts over geological time requires estimating the attenuation of waves approaching cliffs and thus the forces of waves impacting lower cliff surfaces. Sunamura et al. (2014) proposed a set of equations for waves crossing horizontal shore platforms that are potentially useful for geomorphological modelling. Here, we use a compilation of wave measurements to test their equations on dipping platforms and in particular to evaluate the equation parameters. We select only those measurements made where waves approached coastlines nearly orthogonally, where tidal height variations are small and where satellite images show fewer complications from wave refraction, reefs, or coastal geomorphology causing reflected waves. For each dipping rock platform, we forward model the wave heights using the measured wave height at the most seaward location as the boundary condition and apply the Sunamura et al. (2014) equations in a series of small steps across the platform. Using the parameters provided by Sunamura et al. (2014), the model predicts wave heights with a global root-mean square error (RMSE) that is <0.08 m. We repeated the analysis varying parameters by factors of two and four (both smaller and larger), finding that the minimum RMSEs are achieved with exactly the same parameters proposed by Sunamura et al. (2014). This suggests the equations should reliably predict wave attenuation for one-dimensional geomorphologic modelling with those parameters.

Amplification of regional tides in response to sea level

The study investigates the temporal change in tides under the background of rapid sea level rise, for a highly vulnerable coastal region. It highlights the existence of non-astronomic tidal variability at seasonal and secular time-scales in the Ganga-Brahmaputra-Meghna (GBM) delta, along with increasing low and high tidal levels. The observed variability in semi-diurnal tides was found to be coherent to the mean sea level changes. M2 tide can be a proxy for sea level changes as they show a direct relationship. Steric changes were introduced in the barotropic ADCIRC (ADvanced CIRCulation) model and the results proved that change in water depth modulates the energetics of the tidal wave thereby causing amplification. A regionally varying tidal response was noticed, such that the regions associated with the GBM delta showed maximum amplification. The factors that can cause tidal amplification are region-dependent and coastal geomorphology plays an important role in it. Tidal prediction based on changing sea level was able to capture the observed seasonal modulation of tides and increasing trend in low and high tidal levels. Incorporating the effect of changing tides can improve the accuracy of tidal predictions and will help advance studies regarding regional sea level change, coastal flooding and tide-surge interaction.

PERCEPTIONS ABOUT LANDSCAPE AND GEOTOURISM IN THE COASTAL ZONES OF THE STATE OF MARANHÃO THROUGH THE STUDY OF THE ENVIRONMENT AND FIELD CLASSES

This work is based on practical field activities, linked to the “Coastal Geomorphology” discipline, taught in a condensed form (2018.4) provided for the academic calendar of the Federal University of Maranhão. Emphasis is placed on the pedagogical resources addressed as a form of teaching, with the insertion of practical activities that facilitated and optimized learning, through elements that are essential for the fixation of knowledge by students. In the scope of Geography and other sciences such as Geomorphology, Geology and Oceanography, the analysis and understanding of landscape observations, in a scenario of coastal areas of Maranhão State, with emphasis on the exceptional region of “Lencóis Maranhenses”, in the geotourism route, consisted in a great experience, whose elements deserved to be brought and highlighted here.

Coastal Geomorphology and Geospatial Beach Profile Assessment for East Coast Monsoonal Coastlines.

The main concern for this research is slope estimation and the beach profiling with verification sensor-based remotely data (high spatial resolution). Thus, surveying and satellite extraction data need to be accurat. It had been proven to support the relationship between coastal erosion with beach slope changes along Kuantan, Pahang. Therefore, the actual coastline can be mapped from last vegetation features and determine physical condition of beach on coastal habitable land where the baseline has been changes due to sea-level rise event. Hence, the aim of this study is to monitor beach profile using high spatial resolution remote sensing imagery and GIS techniques to distinguish slope estimation from different sources in Kuantan, Pahang Site-verification are done to identify beach slope profiling along Kuantan coastline, Pahang. The objectives of this research are i) to generate coastal slope estimation and beach profile in year 2006 and 2014, ii) to quantify the estimated and observed beach slope from IFSAR data and slope site surveying (by NAHRIM) and iii) to visualise in 3-D view of coastal slope profile derived using IFSAR data. The accuracy values provided for the measurements made in open area, undisturbed area with slopes less than 10 %. From early reconnaissance of Kuantan beach, most of the area are flat and sandy profile to which are suitable for this application. Besides, we found out this method are reliable to produce appropriate slope profile along identified areas in selected Pahang coastline. The findings may indicated a better strategy for monitoring coastline changes is needed especially for vulnerable coastal erosion areas for future sustainable coastal management.

Growth Rate Analysis Casuarina equisetifolia of The Case Study Pacitan and Samas Coast Area

The southern coast of Java is an area that is prone to earthquakes and tsunamis because the area is a meeting of the Pacific plate and the Indo-Australian plate meeting the South American continental plate, and the North American plate meeting the Philippine plate. The tsunami disaster can cause significant loss of life and material and cause damage to infrastructure in coastal areas. Casuarina equisetifolia is one type of vegetation that can grow in the southern coastal area of Java, where the coastal morphology is dominated by sand-type material used for protection from wind waves. The primary survey carried out in this study was to obtain the dimensions of coastal forest plants. The results of the Casuarina measurements were the age of 2 to 4 years at the Samas Coast area and 1 to 9 years were made at Teleng Ria Coast area. The analyzing show that increasing logarithmic function of Casuarina the trend of increasing growth of Casuarina tree height. It ages the older the tree height will increase, but this does not apply to the thickness of the tree canopy that grows to the side, because influenced by the position of the shoreline and the plant spacing factor.

Coastal Geomorphology of West Bengal – A Review

Coastal Geomorphology of West Bengal – A Review

Species Traits and Geomorphic Setting as Drivers of Global Soil Carbon Stocks in Seagrass Meadows

AbstractOur knowledge of the factors that can influence the stock of organic carbon (OC) that is stored in the soil of seagrass meadows is evolving, and several causal effects have been used to explain the variation of stocks observed at local to national scales. To gain a global‐scale appreciation of the drivers that cause variation in soil OC stocks, we compiled data on published species‐specific traits and OC stocks from monospecific and mixed meadows at multiple geomorphological settings. Species identity was recognized as an influential driver of soil OC stocks, despite their large intraspecific variation. The most important seagrass species traits associated with OC stocks were the number of leaves per seagrass shoot, belowground biomass, leaf lifespan, aboveground biomass, leaf lignin, leaf breaking force and leaf OC plus the coastal geomorphology of the area, particularly for lagoon environments. A revised estimate of the global average soil OC stock to 20 cm depth of 15.4 Mg C ha−1 is lower than previously reported. The largest stocks were still recorded in Mediterranean seagrass meadows. Our results specifically identify Posidonia oceanica from the Mediterranean and, more generally, large and persistent species as key in providing climate regulation services, and as priority species for conservation for this specific ecosystem service.

Quaternary E-W Extension Uplifts Kythira Island and Segments the Hellenic Arc.

Several crustal and lithospheric mechanisms lead to deformation and vertical motion of the upper plate during subduction, but their relative contribution is often enigmatic. Multiple areas of the Hellenic Forearc have been uplifting since Plio-Quaternary times, yet spatiotemporal characteristics and sources of this uplift are poorly resolved. The remarkable geology and geomorphology of Kythira Island, in the southwestern Hellenic forearc, allow for a detailed tectonic reconstruction since the Late Miocene. We present a morphotectonic map of the island, together with new biostratigraphic dating and detailed analyses of active fault strikes and marine terraces. We find that the Tortonian-Pliocene stratigraphy in Kythira records ∼100m of subsidence, and a wide coastal rasa marks the ∼2.8-2.4Ma maximum transgression. Subsequent marine regression of ∼300-400m and minor E-W tilt are recorded in ∼12 marine terrace levels for which we estimate uplift rates of ∼0.2-0.4mm/yr. Guided by simple landscape evolution models, we interpret the coastal morphology as the result of initial stability or of slow, gradual sea-level drop since ∼2.8-2.4Ma, followed by faster uplift since ∼1.5-0.7Ma. Our findings on- and offshore suggest that E-W extension is the dominant mode of regional active upper crustal deformation, and N-S normal faults accommodate most, if not all of the uplift on Kythira. We interpret the initiation of E-W extension as the result of a change in plate boundary conditions, in response to either propagation of the North Anatolian Fault, incipient collision with the African plate, mantle dynamics or a combination thereof.

Transport properties of fast ice within the nearshore

Fast ice affects many coastlines in high- and mid-latitude regions, shaping the coastal morphology by acting as both a protective barrier from winter storms and as an erosive agent through sediment entrainment and transport. It has been hypothesized that when sediment-rich ice is dislodged and transported beyond the depth of closure by storm waves, sediment is permanently removed from the nearshore, starving the littoral system and facilitating future erosion. However, despite this large potential impact on coastal sediment budgets, the rates and mechanisms of sediment-rich ice transport are poorly constrained. This study investigates the sediment entrainment process by fast ice, the mechanisms needed for ice mobilization, and the force needed to breakup and transport sediment-rich ice. We find that the Coulomb frictional strength of the sediment regulates the fast ice system and that the viscous rheology of the ice has no direct mechanical effect. Importantly, these results show that only the frictional coefficient of the beach sediment needs to be measured to estimate the resistive strength of the fast ice, significantly simplifying the requirements for evaluating the potential for fast ice mobilization and associated sediment transport. • Investigations on sediment entrainment and mobilization processes for fast ice. • Experiments reveal the force needed to breakup and transport sediment-rich ice. • The frictional strength of the sediment, not ice, regulates the fast ice system. • Blocks of ice with adhered sediment can be treated as a Coulomb material.