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Headland and field edges have a higher traffic frequency compared to the field centre, which causes more compaction. Most repeated compaction is located at the field entrance area and headland during machinery turning and material transporting that takes place during the fertilisation, herbicide laying, and harvesting of fields, which could cause soil structure destruction and yield reduction. In this study, the differences between headland, field edges, and field centre were studied using yield maps and the vegetation indices (VIs) calculated by the Google Earth Engine (GEE). First, thirteen yield maps from 2019 to 2022 were used to measure the yield difference between headland, field edges, and field centre. Then, one hundred and eleven fields from northern Italy were used to compare the vegetation indices (VIs) differences between headland, field edges, and field centre area. Then, field size, sand, and clay content were calculated and estimated from GEE. The yield map showed that headland and field edges were 12.20% and 2.49% lower than the field centre. The results of the comparison of the VIs showed that headlands and field edges had lower values compared to the field centre, with reductions of 4.27% and 2.70% in the normalised difference vegetation index (NDVI), 4.17% and 2.67% in the green normalized difference vegetation index (GNDVI), and 5.87% and 3.59% in the normalised difference red edge (NDRE). Additionally, the results indicated that the yield losses in the headland and field edges increased as the clay content increased and sand content decreased. These findings suggest that soil compaction and structural damage caused by the higher traffic frequency in the headland and field edges negatively affect crop yield.

Ship Shoal is an inner-shelf submarine shoal with large amounts of restoration quality sand that was dredged in 2013–2016 for the Caminada Headland Restoration Project in central Louisiana, USA. Here we provide the first assessment of the characteristics and rate of seasonal sediment infilling the South Pelto dredge pit on eastern Ship Shoal, which will inform future restoration initiatives. Vibracore and multicore samples collected in 2017 and 2018 from within and outside of South Pelto dredge pit revealed new interlaminated silts and clays (median grain size 4.3–6 ϕ, 16–48 µm) deposited at the bottom of the dredge pit, underlain by original Ship Shoal sand and older pro-delta deposits. Through analyzing beryllium-7 (7Be) inventories in multicores, we found that sedimentation rate varied seasonally from 4 to 12 cm (sedimentation rate 0.02–0.06 cm day−1) in fall 2017 to 8 to16 cm (0.05–0.15 cm day−1) in spring 2018. Mapping plume distribution along the continental shelf with satellite imagery corroborated with local wind/wave data revealed that the sediments deposited in South Pelto dredge pit are likely sourced from a combination of the Atchafalaya and Mississippi River plumes during the study period, in addition to possible resuspension from the ambient inner continental shelf and fine-grained material exported from proximal bays. Sedimentation in the dredge pit is not greatly affected by wall slope failure or bedload influx of ambient Ship Shoal sand. Infilling rate and material are slower and finer than past model prediction. Restoration quality sand on this sandy shoal in Louisiana is thus not renewable.

Burullus headland is located in the middle half of the Nile Delta Coast. It extends from Burullus inlet to the east to Kitchener drain outlet to the west. Burullus headland has several types of coastal protection structures, such as seawalls, groins, revetments, jetties, basalt riprap (rock wall), and detached breakwaters; these structures were constructed to mitigate coastal erosion. This study aims to compare rates of shoreline displacement prior to and after the construction of the aforementioned structures and to evaluate their efficiency in protecting Burullus headland from erosion during the period from 1973 to 2018. Multi-temporal satellite images and Digital Shoreline Analysis System software have been used to detect and quantify shoreline changes and to predict the shoreline position at 2030, depending on the resulted rates of shoreline displacement. The analysis showed that Burullus headland coast would be divided into four zones, according to the intensity of the erosion; these are: Zone A with accretion's rate of 0.67 m/year; Zone B, the most affected area by erosion with retreating rate of 4.32 m/year; Zone C, which includes 14 of detached breakwater, showed an accretion rate of 5.62 m/year; and finally, Zone D, which includes 9 groins, was characterized by retreating rate of 2.88 m/year. The results of this study show that some types of protection structures were not effective in mitigating coastal erosion in the case of Burullus headland. The predicted shoreline indicates continuous accretion in zone A and C and continuous erosion in zone B and D.

In the coastal zone of the oceans, there are various coastal systems, among which the most specific are “winged forelands”. Within the Black Sea coast there are four “winged forelands”: Tendra–Dzharylgach, Kinburnska–Pokrovska–Dovgiy, Burnaska–Budatska and Lebedyna–Ustrychna, which named by same structural ones. The purpose of the publication is to systematize the primary information about the morphological features of the coastal zone of the barrier system type ‘winged foreland” Kinburnska–Pokrovska–Dovgy which was obtained during field research.During the natural research in 2019, within the most typical areas of the coastal zone, reference benchmarks and morphological profiles were laid and recorded by a GPS. The total length of the coastal system is about 35 km, within its boundaries there are 7 benchmarks, which contains for 1 benchmark per 5 km, and a systematic geomorphological survey of 20 profiles (1 profile per 1.75 km) is carried out. Relevant indicators suggest that the results of the research are reliable.Morphologically, the studied system is a “winged foreland”, within which there are four structural and morphological elements: Kinburnska Spit, Frontal Coast or “headland”, Pokrovska Spit with the islands of Kruglyi and Dovhyi. Kinburnska Spit is a free accumulative coastal form located in the northwestern part of the Kinburn Peninsula. Morphogenetically, it is an arrow that develops in the conditions of bilateral feeding by beach sediments. The Frontal Coast or “headland” is the central component, within which the sand massifs of the Kinburn Peninsula go directly to the coastal zone. Pokrovska spit with the islands of Krugliy and Dovhiy is a relict generation, which is genetically an ancient accumulative form divided into three components. All these components are located on the surface of the base of the ancient coastal form, and their development occurs in conditions of limited supply of beach sediments. The front of the Pokrovsky Peninsula with the Sukha Spit and the Island Bar “Zagreba” is a modern accumulative generation that is actively increasing in size and advancing towards the waters of Tendra Bay.Key words: coastal systems, “winged foreland”, coastal zone, underwater slope, shore, coastal systems, foredunes У береговій зоні Світового океану існують різноманітні берегові системи, серед яких найбільш специфічні «крилаті миси». У межах узбережжя Чорного моря виділяються чотири «крилаті миси»: Тендра–Джарилгач, Кінбурнська–Покровська–Довгий, Бурнаська–Будацька та Лебедина–Устрична. Мета публікації полягає у систематизації та оприлюдненні первинної інформації про морфологічні особливості берегової зони бар’єрної системи типу «крилатий мис» Кінбурнська–Покровська–Довгий, отриманої під час польових досліджень 2018–2021 рр. Загальна довжина дослідженої берегової системи близько 35 км, в її межах закладено 7 репер-них стаціонарних ділянок та проводиться систематична геоморфологічна зйомка на 20 профілях, положення яких зафіксовано за допомогою GPS-приймача. Розроблена система стаціонарних ділянок і геоморфологічних профілів дозволяє надійно проводити довготермінові спостереження в масштабі 1:10000. Відповідні показники дозволяють вважати, що результати проведених досліджень є достовірними.У морфологічному відношенні досліджувана система є «крилатим мисом», в її межах виділяються чотири структурно-морфологічні елементи: Кінбурнська коса, Фронтальний берег, Покровська коса з островами Круглий та Довгий, Фронт Покровського півострова із Сухою косою та острівним баром «Загреба».Кінбурнська коса – це вільна акумулятивна берегова форма, розташована у північно-західній частині Кінбурнського півострова. В морфогенетичному відношенні це стрілка, яка розвивається в умовах двостороннього живлення прибережно-морськими наносами. Фронтальний берег, або «лобище», є центральним складовим елементом, у межах якого безпосередньо до берегової зони виходять піщані масиви Кінбурнського півострова. Покровська коса з островами Круглий та Довгий є реліктовою генерацією, яка в генетичному відношенні є давньою акумулятивною формою, поділеною на три складники. Всі перелічені складники розташовані на поверхні цоколю давньої берегової форми, а їх розвиток відбувається в умовах обмеженого живлення прибережно-морськими наносами. Фронт Покровського півострова із Сухою косою та острівним баром «Загреба» являє собою нову акумулятивну генерацію, яка активно збільшується у розмірах та висувається в бік акваторії заток.Ключові слова: берегові системи, «крилатий мис», підводний схил, берег, підводний вал, авандюна.

There is increased stress on soil and crop quality caused by machinery traffic during field operations in tillage systems, especially the area where the machinery turns, known as the headlands. Whi...

An investigation by Headland Archaeology (UK) Ltd took place in late 2002 ahead of the extension of a sand and gravel quarry near Thankerton, South Lanarkshire. Excavations revealed domestic activity dating from the middle Neolithic to the late Bronze Age, with a further phase of activity in the early historic period. Middle Neolithic pits were recorded across the site and contained sherds of Impressed Ware, a polished stone axe and an assemblage of lithics. Following the middle Neolithic there appears to have been a hiatus in activity until the Bronze Age. Several late Bronze Age features were recorded including at least two ring-ditches. The latest feature on site is a bicameral enclosure, with a possible palisade of uncertain date.

This contribution focuses on a multidisciplinary research showing the geomorphological evolution and the beach sand composition of the Tyrrhenian shoreline between Capo Suvero promontory and Gizzeria Lido village (Calabria, southern Italy). The aim of the geomorphological analysis was to reconstruct the evolutionary shoreline stages and the present-day sedimentary dynamics along approximately 6 km of coastline. The results show a general trend of beach nourishment during the period 1870–2019. In this period, the maximum shoreline accretion value was estimated equal to + 900 m with an average rate of + 6.5 m/yr. Moreover, although the general evolutionary trend is characterized by a remarkable accretion, the geomorphological analysis highlighted continuous modifications of the beaches including erosion processes. The continuous beach modifications occurred mainly between 1953 and 1983 and were caused mainly by human activity in the coastal areas and inside the hydrographic basins. The beach sand composition allowed an assessment of the mainland petrological sedimentary province and its dispersal pattern of the present coastal dynamics. Petrographic analysis of beach sands identified a lithic metamorphi-clastic petrofacies, characterized by abundant fine-grained schists and phyllites sourced from the crystalline terrains of the Coastal Range front and carried by the Savuto River. The sand is also composed of a mineral assemblage comparable to that of the Amato River provenance. In terms of framework detrital constituents of QFL (quartz:feldspars:aphanitic lithic fragments) and of essential extraclasts, such as granitoid:sedimentary:metamorphic phaneritic rock fragments (Rg:Rs:Rm), sand maturity changes moderately from backshore to shoreface, suggesting that transport processes had a little effect on sand maturity. Moreover, the modal composition suggests that the Capo Suvero promontory does not obstruct longshore sand transport from the north. Indeed, sands displaced by currents driven by storm-wave activity bypass this rocky headland.

Within the context of in-field path planning this paper discusses freeform path fitting for the minimisation of the number of transitions between headland path and interior lanes within agricultural fields. This topic is motivated by two observations. Due to crossings of tyre traces such transitions in practice often cause an increase of compacted area. Furthermore, for very tight angles between headland path and interior lanes undesired hairpin turns may become necessary due to the limited agility of in-field operating tractors. By minimising the number of interior lanes both detrimental effects can be mitigated. The potential of minimising the number of interior lanes by freeform path fitting is evaluated on 10 non-convex real-world fields including obstacle areas, and compared to the more common technique of fitting straight interior lanes., Comment: 7 pages, 6 figures, 1 table

The shoreline of northern Colombia is located in the tropical zone along the south coast of Caribbean Sea. Its coastal processes are strongly influenced by the northeast trade wind, which results in the dominating northeasterly approaching wave occurring over 95% of the time. This drives a persistent southwestward longshore sand transport. The state of the beach along the generally northeast-southwest trending northern Colombia coast is strongly influenced by this constant unidirectional longshore sediment transport. At locations where this westward longshore sand transport is interrupted, naturally or anthropogenically, beach accretion occurs along the updrift shoreline coupled with erosion at the downdrift side. Natural interruption of longshore transport can be caused by tidal inlets, protruding headland, shoreline orientation change, and nearshore bathymetry variations. Anthropogenic interruption of the longshore transport along the northern Colombia coast is mainly caused by the construction of groins, as well as harbors at some locations. Numerous groins were constructed due to their local success in creating beach accretion at the drift side. However, severe beach erosion occurs along the downdrift shoreline. Shoreline protection along the northern Colombia coast, and coasts in the tropical area in general, should carefully consider the persistent unidirectional longshore sand transport and should not be misguided by the local updrift accumulation as being a successful project.

Problem statement and purpose. There are various coastal systems in the coastal zone of the World Ocean. The most specific of them are "winged foreland". These natural formations are characterized by certain genetic features, including: morpho­logical, lithodynamic and hydrological. Within the Black Sea coast there are four "winged foreland": Tendra-Dzharylgach, Kinburn-Pokrovs'ka-Dovhyi, Budak-Bour­nas and Lebedyna-Ustrychna. "Winged foreland" Lebedyna-Ustrychna is the smallest formation of this type, which is located along the front of the Hirkyi Kut Peninsula.This coastal system is practically not studied, and the existing information is not sys­tematized. That is why in this article we have presented the materials of many years of field research. We have defined morphological, morphometric and partially litho­logical conditions of the corresponding system.The purpose of the publication is to report on new information on the results of many years of field research on the morphology and morphometry of the coastal system of the "winged foreland" Lebedyna-Ustrychna. Main tasks: are to give a general descrip­tion of the coastal system Lebedyna-Ustrychna; determine the morphometric features of the system and its components; describe the morphological and analyze the lith­ological conditions of the corresponding "winged foreland". The object of the study is the coastal system of the "winged foreland" Lebedyna-Ustrychna. The subject of the study are the geomorphological conditions of the coastal zone of the Hirkyi Kut Peninsula, within which the system under study is located.Data & Methods. Our publication is based on the materials of many years of field research of the coastal zone of the Hirkyi Kut Peninsula, which were conducted by the author with a certain frequency from 1997 to 2020. During the field research, the Garmin eTrex 10 navigator was used to GPS the key areas of the coastline, as well as the locations of geomorphological leveling and sampling points of coastal sediments. Sediment sampling was carried out at key points of the coastal zone within the profile. The leveling materials in Microsoft Excel were used to calculate and construct hypso­metric profiles of the coastal zone. The exact location of the profiles was determined using GPS navigator data and Google Earth. Particle size analysis of sediment sam­ples was performed using a set of sieves and electronic scales.Results. The Lebedyna-Ustrychna coastal system is the smallest "winged foreland" within the not tidal seas. Territorially, it is located in the northwestern sector of the Black Sea, along the front of the Hirkyi Kut Peninsula. The total length of the coastal system is 6.1 km, within its boundaries there are two oppositely located accumulative forms and the root section of the shore or "headland" between them. Lebedyna spit is a small sedimental form about 0.35 km long, with a width of 18 to 50 m, with an area that has seasonal and perennial dynamics. Ustrychna spit is a sedimental form of triangular shape, the length of which is about 1.6 km, with a width of 450 to 25 m, with an area that has constant parameters and low dynamics. "Headland" has a length of about 4.15 km. Morphologically, it is represented by abrasion cliffs with a height of 0.5 to 7 m, as well as port and shore protection structures.Morphologically, the Lebedyna-Ustrychna coastal system is a typical "winged fore­land". Its most important feature is two symmetrically arranged triangular accumu­lative forms. There is a storm shaft composed of stone along the frontal part of both formations. It is composed of "kamka" (dead remains of seaweed Zostera marina), shell and detritus, it is adjoined in certain areas by phytogenic beaches, usually of a complex nature. There are windy flats, small secondary accumulative forms and lagoons are widespread, within the back side of alluvial forms. In certain areas of the accumulative forms relict or modern washing forms of relief are manifested. Within the “headland” there are abrasion, abrasion-collapse and abrasion-subsidence cliffs.The greatest specific feature of the coastal system of Lebedyna-Ustrychna is the litho­logical structure of accumulative forms. The body of the Lebedyna spit is represented by layered shell, detrital, phytogenic and sandy deposits, which are strongly silted up. Ustrychna spit is characterized by a compacted silty base, on the surface of which there is a layer of detrital and phytogenic sediments, significantly silted up.

The ‘guano of the islands’ in Peru is the excrement of cormorants, boobies and pelicans (guano birds), accumulated in large deposits on islands and headlands. This guano is harvested and marketed by the governmental agency AGRORURAL to meet the demands of local organic agriculture. As part of its management and commercialization plans, AGRORURAL estimates the total quantity of guano built-up on the seabird colonies using a volumetric method. The objective of this research was to propose an alternative geostatistical method that uses the volumetric data collection as baseline but incorporates the slope of the terrain and makes estimations of the total amount and distribution of guano using an interpolation grid model in a Geographic Information System (GIS). The data of the slope of the terrain, depth of guano layer, guano density and proportion guano/rock of georeferenced sampling points (taken with a hand-held GPS) on the island/headland surface were used to interpolate the quantity of guano over the entire surface using a raster kriging model so that each cell contained an estimated quantity of guano. For this study, six guano bird colonies were visited between June 2014 and February 2018. Based on the geostatistical method, the total quantity of guano estimated varied between 10921 t on Isla Mazorca and 26142 t on Isla Guanape Sur. The GIS grid maps showed that the quantity of guano deposits was not uniformly distributed over the island/headland surface. When the guano total quantity estimates based on the geostatistical method were validated with the amount of guano harvested, the estimation error was less than 18%. This error may decrease with the use of a submetric GPS, ground-penetrating radars and augers. An accurate method of guano volume quantification is crucial for budget, logistic and marketing planning of the guano islands and headlands of Peru.

Complexities of terrestrial boundaries with salt marshes in coastal lagoons affect salt marsh exposure to waves and sediments creating different potentials for marsh migration inland and seaward-edge erosion, and consequently, for marsh persistence. Between 2002 and 2017, migration and edge erosion were measured in three mainland geomorphic marsh types (headland, valley, hammock) and were used to assess the rate and spatial extent of marsh change for a Virginia coastal lagoon system. Treelines, shorelines, and marsh perimeters were delineated in ArcGIS at 1:600 resolution. All marsh types increased in spatial extent; increases were greatest for the valley type (0.58 ha ± 0.31 ha or + 0.32% per annum). Measured rates of migration (headland > valley > hammock) and erosion (headland > hammock > valley) for each geomorphic type were averaged and applied to obtain changes in these same marsh types at the regional scale. At this scale, valley marsh area increased (82.5 ha or 5.5 ha a−1) more than the other two marsh types combined. This analysis demonstrates the critical influence that geomorphic type has on lateral marsh responses to sea-level rise and that efforts to conserve or restore salt marshes are most likely to be successful when focused on valley marshes.

The headland-bay beach is one of the most common coastal types in the world. Its morphology reflects the changes that occurred during long-term evolution of the sandy coast. Several headland-bay beach models have been proposed to simulate the coastline’s configuration in equilibrium. In this paper, a new elliptical model is proposed, described, and applied. On the east coast of Laizhou Bay in Shandong Province from Longkou Port to Diaolongzui, four typical headland-bay beaches have developed, and four headland-bay beach models are used in this paper to simulate the morphology of these beaches to assess the applicability of each model. The simulation results of the elliptical model verify that it is applicable to the study area. In addition, the elliptical model is easy to use. Through simulation and field investigations, we concluded that most of the coastal segments in this area will remain in an erosion state, and the human activity has a significant impact on the shoreline’s evolution.

Tsunamis are one of the most catastrophic natural hazards that can devastate coastal regions. Most common mechanisms that generate tsunamis are undersea earthquakes and submarine landslides. However, in enclosed basins, such as fjords, reservoirs, and lakes, subaerial landslides can also generate devastating tsunamis with similar or worse consequences, because of a more efficient wave generation. Here, we present the validation of a three-dimensional (3D) numerical model, TSUNAMI3D, by comparing numerical results with a set of subaerial landslide laboratory experiments carried out in the large tsunami wave basin at the Oregon State University (OSU). Results obtained from the laboratory experiments show that subaerial landslides generate highly non-linear waves with complex wave patterns and runup, challenging existing numerical models. The 3D numerical model is first verified with a commercial code, FLOW3D, to obtain a compromise between the model’s spatial-time resolution accuracy and computational cost. Second, the 3D numerical model and the commercial code are validated with a set of OSU laboratory experiments comprising three different layouts or basin configurations, namely, fjord, curved headland, and basin-wide. Simplified material rheology and key parameters required for modeling subaerial landslides are defined. Numerical models’ relative errors are estimated and analyzed, and the models’ limitations are discussed. In general, numerical models’ relative errors are found to be acceptable in most of the validation tests except those tests located close to the wave generation region. Validation results confirm that the 3D numerical models with simplified landslide rheology can be used to understand and reproduce the complex non-linear wave propagation and runup generated by subaerial landslides. Thus, TSUNAMI3D can help assess tsunami hazards in communities located in proximity to potential subaerial landslides. Also, the set of physical experiments can be used for further numerical validation efforts, helping tsunami organizations, e.g., the National Tsunami Hazard Mitigation Program, to amend existing or develop better numerical models and thus, improve inundation/evacuation mapping products that would save lives and property.

Water current flow characteristics represent crucial information required for the management of coastal tourism destinations. Strong currents or strange flow patterns can pose risks to beach visitors. This research examined the currents at Pattaya Bay, one of the most famous beaches in the world. Numerical simulations were undertaken. Sophisticated simulation techniques were applied so that the calibrated simulation results were reliable. A whirlpool at the southern part of the bay was discovered, occurring every day during flood tides. The vortex rotated clockwise, with a magnitude between 0.34 and 0.41 m/s, and its radius could sometimes reach 500 m. The swirl was a natural phenomenon since it was created by the oblique orientation of the southern headland. The whirlpool was not deadly since its strength was normal for open coastal waters. However, care should not be neglected. This research raised awareness about the whirlpool's existence, so that proper management can be exercised.

Headland sediment bypassing relates short-term physical forcing and long-term morphological response. The contributions from King et al., 2021 are a substantial step in understanding the complexiti...

Two-dimensional models of large spatial domain including Cua Lo and Cua Hoi estuaries in Nghe An province, Vietnam, were established, calibrated, and verified with the observed data of tidal level, wave height, wave period, wave direction, and suspended sediment concentration. The model was then applied to investigate the hydrodynamics, cohesive sediment transport, and the morphodynamics feedbacks between two estuaries. Results reveal opposite patterns of nearshore currents affected by monsoons, which flow from the north to the south during the northeast (NE) monsoon and from the south to the north during the southeast (SE) monsoon. The spectral wave model results indicate that wave climate is the main control of the sediment transport in the study area. In the NE monsoon, sediment from Cua Lo port transported to the south generates the sand bar in the northern bank of the Cua Hoi estuary, while sediment from Cua Hoi cannot be carried to the Cua Lo estuary due to the presence of Hon Ngu Island and Lan Chau headland. As a result, the longshore sediment transport from the Cua Hoi estuary to the Cua Lo estuary is reduced and interrupted. The growth and degradation of the sand bars at the Cua Hoi estuary have a great influence on the stability of the navigation channel to Ben Thuy port as well as flood drainage of Lam River.

Sand-mud transition (SMT) is an important boundary of the beach system, and its location and evolution have been increasingly studied in recent years. This study focuses on the location and migration of SMTs and their influencing factors on three representative embayed beaches on the east coast of Zhujiajian Island, Zhejiang Province, China, characterized by different levels of human interventions. Beach topographies, surficial sediment characteristics and nearshore hydrodynamic data were obtained through three field campaigns carried out during the early, middle and late stages of the 2019 typhoon season. This typhoon season included four typhoons with nearshore significant wave height Hs exceeding 3.71 m, and maximum Hs of 6.77 m (Super Typhoon Lekima). Results show that the three beaches were all impacted by the high-energy wave conditions, although with some different behaviors. Sediments of the three beaches all coarsened with worse sorting during the typhoon season, with the nearshore surficial sediments showing similar patterns. The SMTs of the three beaches were stable or migrated seaward during the typhoon season. During the typhoon season, offshore SMT migration was positively correlated with the beach profile volumetric loss at three embayed beaches in this study. The SMTs of beaches with less human intervention are more stable during typhoon season. By including 12 additional embayed beaches of eastern China in our analysis, we found that the SMT offshore distance increases with increasing nearshore average significant wave height, increasing headland offshore extent and decreasing tidal range. Our study suggests that SMT is a relevant indicator of beach sediment stability, which can help to increase the understanding of embayed beach dynamics and to guide coastal management and planning during typhoon seasons at such embayed beaches.

Table Bay, South Africa, is a typical headland-bay system with a shoreline that can be described by a logarithmic spiral. A peculiarity and unique feature of Table Bay is the juxtaposition of Robben Island opposite its headland. As a consequence, the bathymetry defines an ellipsoidal basin which was postulated to potentially resonate in the form of long-period standing waves (seiches). One aim of this study, therefore, was to investigate whether any evidence for such resonant oscillations could be detected in the geomorphology and sediment distribution patterns. Indeed, the ellipsoidal shape of the basin can be framed by two converging log-spirals with their centres located opposite each other, one off Robben Island and the other on the Cape Town side of the bay. The so-called apex line, which divides the two spirals into equal parts is aligned SW–NE, i.e. more or less parallel to the direction of ocean wave propagation. The distribution patterns of all sedimentary parameters were found to be characterised by a strikingly similar trend to either side of the apex line. This supports the hypothesis that the basin of Table Bay appears to resonate in the form of a mode 1 standing wave, with the node positioned above the apex line in the centre of the bay. The maximum period of such a standing wave was calculated to be around 37 min. The study demonstrates that large-scale sediment distribution patterns can reveal the existence of specific hydrodynamic processes in coastal embayments. It is recommended that this phenomenon be investigated in greater detail aimed at verifying the existence of resonant oscillations in Table Bay and, in the event, at establishing its precise nature and trigger mechanism.

The coastal vulnerability to multi-hazard study aims to assess the coastal zones of Andhra Pradesh that really are vulnerable to various oceanogenic hazards. Using high-resolution coastal elevation, the maximum extent of coastal inundation during extreme high waves of cyclones & tsunamis, shoreline change, and sea-level rise can be computed. Vulnerability impact up to the village level was assessed based on future projection (return period) of multi-hazard impact using a holistic approach with geospatial techniques. The current study results revealed that 706 villages and 8 towns that are completely falling under CMZ are at risk. A total of 9682 km2 of coastal zones of Andhra Pradesh coast are exposed and prone to inundation as recorded under CMZ. Krishna, Godavari, Guntur and Prakasham districts comprise 70% of the total CMZ area are large low-lying areas exposed to ocean hazards. CMZ area along Andhra Pradesh coast recorded a significant negative correlation of − 0.65 with coastal elevation and a positive correlation of 0.34 with coastal exposure index. Shoreline change assessed from 1972 to 2019 across the study area reveals the 7% under high erosion along the headland and low-lying area of Krishna-Godavari delta. The outputs and maps produced in this study provide vital input for coastal disaster management and necessary policy interventions.

Offshore storm wave direction may distinguish between an extreme event and a typical event experienced at nearshore. Using a state-of-the-art spectral wave (SW) model, the purposes of this study are: (1) to investigate the transformation of waves from offshore to nearshore along the coastline from two opposite directions (northerly and southerly); and (2) to analyse the offshore wave energy density spectrum. The SW model was calibrated considering various mesh resolutions and lateral wind forcing with different wind field resolutions. The results show that a longshore wave attenuation gradient exists from the southerly swell, primarily due to different degrees of sheltering provided by the headland. In contrast, the coast essentially becomes an open coast from northerly swells, thereby producing a significant reduction in wave attenuation. The wave energy density spectrum indicates that wave pattern varies depending on offshore wave direction. Both storms produce a wide range of frequencies and directions. However, southerly swells only produce single-peaked spectrum, while double-peaked spectrum is observed in northerly swells due to the presence of prevailing swells and storm swells. This study highlights the significant reduction of wave attenuation when predominate offshore wave direction is abrupted.

Embayed beaches separated by irregular rocky headlands represent 50% of global shorelines. Quantification of inputs and outflows via headland bypassing is necessary for evaluating long-term coastal...

A coastal area has important and vital influences on community’s lives due to the natural resource availability. The coastal area occurs any changes over time affecting the changes in the community and in the ecological perspectives. Banda Aceh is one of the coastal areas that has experienced several significant changes especially after earthquake and tsunami on December, 26th 2004. Due to the condition, it is required to analyze coastal vulnerability in Banda Aceh and neighbor. This research was aimed to investigate the influences of physic parameters consisting of hydrodynamic and morphology parameters on determining Coastal Vulnerability Index (CVI). The analysis will determine the coastal vulnerability index in one year period. The analysis was carried out in the northern coast of Aceh Province, between Ujong Pancu and Ujung Batee by dividing the areas into 5 (five) cells bordered by natural morphology feature such as inlet, headland, river estuary, and lagoon. Based on 6 (six) physical parameters used on coastal vulnerability index (CVI) determination, it is obtained that 2 cells have low risk potential (green), which are Cell 1 and Cell 3 with the CVI values are 2.45 and 3.0, respectively. Cell 2 has moderate risk potential (yellow) with CVI value is 4.24. Meanwhile, Cell 4 and Cell 5 have high risk potential (red) with CVI values are 5.20

Significance We demonstrate that a tsunami in the late 14th century CE destroyed coastal sites along a critical part of the maritime Silk Road and set in motion profound changes in the political economy of Southeast Asia. Our results provide a precise chronology of settlement and trade along a historically strategic section of the Sumatran coast and are robust physical evidence for the rise of the Aceh Sultanate. Tragically, coastal areas impacted by the late 14th century tsunami were devastated by the 2004 Indian Ocean tsunami. This makes our findings relevant to debates about hazard mitigation and risk reduction. This example shows that archaeological, historical, and geological data are relevant in discussions about the long-term sustainability of communities exposed to geological hazards., Archaeological evidence shows that a predecessor of the 2004 Indian Ocean tsunami devastated nine distinct communities along a 40-km section of the northern coast of Sumatra in about 1394 CE. Our evidence is the spatial and temporal distribution of tens of thousands of medieval ceramic sherds and over 5,000 carved gravestones, collected and recorded during a systematic landscape archaeology survey near the modern city of Banda Aceh. Only the trading settlement of Lamri, perched on a headland above the reach of the tsunami, survived into and through the subsequent 15th century. It is of historical and political interest that by the 16th century, however, Lamri was abandoned, while low-lying coastal sites destroyed by the 1394 tsunami were resettled as the population center of the new economically and politically ascendant Aceh Sultanate. Our evidence implies that the 1394 tsunami was large enough to impact severely many of the areas inundated by the 2004 tsunami and to provoke a significant reconfiguration of the region’s political and economic landscape that shaped the history of the region in subsequent centuries.