Northern Coastline Research Articles

A 45-year updating wind and wave hindcast over the Oman Sea and the Arabian Sea

This study focuses on developing a comprehensive and reliable wind and wave hindcast for the Oman Sea and Arabian Sea, spanning a significant 45-year period (1979–2024). The objective is to capture the intricate wind and wave climate of the region, characterized by distinct monsoon cycles and occasional tropical cyclones. The availability of extensive wave data over four decades would be an irreplaceable tool for researchers and engineers, enabling improved accuracy in extreme value analysis, sediment transport studies, and wave-induced current simulations. Despite limited field observations, all available measured data within the region were collected, analyzed for configuration of the models and utilized for model calibration and validation. The hindcast data was generated using the Weather Research and Forecasting (WRF) model for winds and WAVEWATCH III (WW3) model for waves, and evaluated against observational and measured wind and wave parameters. A comprehensive statistical analysis of the hindcast model's performance reveals adequate agreement with measured data, as evidenced by root mean square errors (RMSEs) of 1.23 m/s for wind speeds and 0.37 m for significant wave heights in average. These results underscore the model's reliability for research and engineering applications, particularly in the Arabian Sea, with a focus on the northern coastlines of the Oman Sea. The specific model configuration employed in this study holds significant potential for future investigations in the northern Indian Ocean, offering a valuable tool for understanding and predicting climatical conditions in this region.

First records of Glyphus marsupialis Filhol, 1884 (Decapoda: Pasiphaeidae) in southwestern Atlantic deep waters and extensions of the known distribution of two Pasiphaea species

The Pasiphaeidae Dana, 1852 are a marine shrimp family occurring in both shallow and deeper waters, with its greatest diversity occurring in tropical and subtropical deep seas. This family includes seven genera and 104 species, and is globally distributed. Currently, the genus Pasiphaea Savigny, 1816 includes 73 species, seven of them recorded in the southwestern Atlantic. The genus Glyphus Filhol, 1884 is monotypic and is known from the Indo-Pacific region, the East Pacific Ocean and in the Eastern Atlantic. Herein, we report the first record of the genus in the southwestern Atlantic, completing a cosmopolitan distributional pattern. Further, two new records of Pasiphaea species are commented upon (P. major Hayashi, 2006; P. tarda Kroyer, 1845) along the Northern coastline of the Brazilian coast (Amapá state), also reporting a new host interaction between Thalassomyces sp. and P. major. This is the first record of this Ellobiopsidae genus in the South Atlantic Ocean. The material herein analyzed was sampled by the ReviZEE Program/North, in 1996/2001, during deep-water trawls in the Amazonian slope (Amapá state), at depths from 250 to 1100 m. All material is deposited in the Coleção Carcinológica do Laboratório de Crustáceos (Labcrus)/Universidade Federal Rural da Amazônia (UFRA). The global distribution of Glyphus is commonly observed in deep species and although it has been occasionally contested by the discovery of species complexes (using very detailed morphological and molecular data analyses) with the currently available information, the present material is clearly identifiable as G. marsupialis.

The Tournament at Saint-Inglevert (1390): Chivalry, Diplomacy and Pas d’armes

ABSTRACT In March and April 1390, three French knights jousted against over one hundred knights and squires who had travelled from across Europe to challenge them, but above all from England. This great tournament was held at Saint-Inglevert near to Calais, the English outpost on the northern coastline of France. Modern scholars have viewed the event through the lens of the on-going Hundred Years War. But rather than seeing this chivalric competition as an extension of the war between the two sides, it should rather be understood as part of the diplomatic engagement between Charles VI and Richard II during the 1390s, an informal opportunity for the elites to meet and form bonds that shaped the rapprochement between the two sides. Saint-Inglevert also marked an important stage on the path towards the great theatrical tournaments of the fifteenth century, helping to explain the rise in popularity of the famous pas d’armes.

Spatial and temporal trend analysis of temperature extremes in Tanzania

This study examines the effects of extreme temperature events, defined explicitly as the 98th percentile temperature for heat, in Tanzania from 1981 to 2023. The study utilises percentile analysis, z-score calculations, and trend mapping to highlight the prevalence of extreme temperatures. The z-score analysis examines the occurrence of extreme temperatures and their distribution in terms of frequency and space. It identified Tanzania’s mid-eastern and north-western regions as areas with a high concentration of extreme temperatures over the previous 43 years. The study analyses the length of extreme occurrences and reveals changing patterns. In 2020, the events were shorter, while in 2021 and 2022, they became longer-lasting, and there was a notable concentration of extended anomalies near the northern coastline. In 2023, the highest temperatures ever recorded were observed, with more than half of the regions seeing prolonged periods of extreme temperatures lasting for a week and significant deviations from the norm staying for four weeks or more. This was particularly notable in the southern regions of Lindi and Mtwara. The harmonic trend analysis of temperature shows an upward temperature trend noticeably in regions such as Arusha, Kilimanjaro, Kagera, Morogoro, Simiyu, and Shinyanga and is somewhat inconspicuous in most areas.

Increasing fluctuations in the Arctic summer sea ice cover are expected with future global warming

The loss of Arctic sea ice (ASI) represents a major transformation in the Arctic region, impacting regional and global climate, ecosystems, and socio-economic structures. Observational and reanalysis data have consistently shown a notable shift in polar environmental conditions over recent decades, marked by a substantial reduction in the ASI area and a rise in the variability in its coverage and distribution. Utilizing data from the latest Coupled Model Intercomparison Project phase, our study reveals a consistent pattern highlighting a fundamental shift in ASI dynamics preceding total loss. We observe increasing fluctuations in the September ASI area as the threshold for an ice-free Arctic is approached across various scenarios and models. This pattern is particularly concentrated in the Central Arctic (CA) sub-region. Spatial analyses reveal increasing variance along the CA’s northern coastlines, accompanied by a substantial increase in open water coverage, underscoring the shift from stable to highly variable ice conditions in this region. Additionally, our findings suggest a potential link between increased ASI fluctuations and variability in surface wind speeds. These specific results underscore the urgency of multidisciplinary approaches in addressing the challenges posed by ASI variability, with implications for marine ecosystems, Indigenous communities, and navigational safety.

Smallpox Geographies: vaccination, borders and Indigenous peoples in Australia's coastal north.

Australia's approach to its biosecurity and borders has always been two-pronged - quarantine first, vaccination second. This article asks what this combination looked like in practice by exploring two neglected smallpox vaccination campaigns directed towards Indigenous peoples in the early twentieth century. We argue these were important campaigns because they were the first two pre-emptive, rather than reactionary, vaccination programs directed towards First Nations people. Second, both episodes occurred in Australia's northern coastline, where the porous maritime geography and proximity to Southeast Asia posed a point of vulnerability for Australian health officials. While smallpox was never endemic, (though epidemic), in Australia, it was endemic at various times and places across Southeast Asia. This shifting spectre of smallpox along the northern coastline was made even more acute for state and federal health officials because of the existing polyethnic relationships, communities, and economies. By vaccinating Indigenous peoples in this smallpox geography, they were envisioned and embedded into a 'hygienic' border for the protection of white Australia, entwining the two-prongs as one approach. In this article, we place public health into a recent scholarship that has 'turned the map upside down' to re-spatialise Australia's history and geography to the north and its global connections, while demonstrating how particular coastlines and their connections were drawn into a national imaginary through a health lens.

Holocene peopling and sea-level changes along the northern coast of the Arabian Sea (Pakistan)

Surveys carried out in the provinces of Las Bela and Lower Sindh (Pakistan) have led to the discovery of many concentrations of knapped stone artefacts associated with mangrove and sea shells. The most important group of sites has been discovered along the shores of Lake Siranda (Balochistan) and on the limestone terraces that rise from the Indus Plain in Lower Sindh. The radiocarbon dates obtained from the Lake Siranda sites have shown that the ancient lagoon was seasonally settled between the last two centuries of the 8th and the end of the 5th millennium uncal BP that is from the beginning of the Neolithic to the Bronze Age. Although more research is needed, we now know the important role played by the coastal zones of Las Bela and Lower Sindh in the Holocene archaeology of the Arabian Sea, the only region of the northern coastline that has provided evidence of Neolithic and Chalcolithic settlement. The Neolithic knapped stones discovered during the surveys consist of bladelet artefacts and geometric microliths made from local cherts, while the Chalcolithic Amri Culture implements are obtained from exotic flint. Since the beginning of the Holocene the coastal zone has been affected by dramatic events among which are sea-level rise, tectonic activity, subsidence, and the advance of the Indus Delta. The present landscape shaped around the end of the Bronze Age, when arid conditions established and the Indus Civilisation declined. Unfortunately many of the coastal sites are in danger or have been destroyed by industrial development.

Changes of Yancheng coastline near 20 years based on remote sensing technology

The study of coastline changes is crucial for the monitoring, development, and management of coastal environments. This article specifically focuses on the coastline of Yancheng. To analyze the changes of coastline, latest remote sensing images of Landsat series from 2002 to 2021 were selected. Threshold segmentation was employed to extract the coastline from these images. Subsequently, tidal level correction was applied to rectify the instantaneous water edge in the binary image of the target coastal area based on tidal channels, resulting in the acquisition of the target coastline. Finally, the obtained target coastline from different time periods were inputted into the Digital Shoreline Analysis System (DSAS). DSAS can be used to assess coastline changes using the end point change rate (EPR) and linear regression change rate (LRR). The research findings reveal that the average siltation rate of various sections along the Yancheng coastline is 105.62 m/y, with the maximum siltation length measuring 12,048 m, located in the Tiaozini reclamation area. Conversely, the maximum erosion length is 1820 m, situated near the mouth of the Shuangyang River. Taking the Sheyang River mouth as the boundary, the northern coastline of the river mouth experiences predominantly erosion, while the southern coastline is primarily affected by sedimentation. Moreover, the rate of coastline change gradually increases from north to south. The transformation of artificial coastline is the outcome of a combination of natural and human factors. Agricultural reclamation, port construction, and coastal protection engineering are identified as the main reasons for the artificial and seaward advancement of coastline. This study provides a foundation for the construction and protection of Yancheng’s coastal zone and offshore engineering. It holds significant practical implications for urban planning and development.

Mesoscale Convective Systems and Extreme Precipitation on the West African Coast Linked to Ocean–Atmosphere Conditions during the Monsoon Period in the Gulf of Guinea

This study investigates the importance of convective systems for extreme rainfall along the northern coast of the Gulf of Guinea (GG) and their relationship with atmospheric and oceanic conditions. Convective system data (MCSs), daily precipitation, sea surface temperature (SST) and moisture flux anomalies from June to September 2007–2016 are used. The results show that 2/3 of MCSs crossing Abidjan are produced in June, which is the core of the major rainy season. Likewise, 2/3 of MCSs originate from continental areas, while 1/3 come from the ocean. Oceanic MCSs are mostly initiated close to the coast, which also corresponds to the Marine Heat Waves region. Continental MCSs are mostly initiated inland. The results also highlight the moisture flux contribution of three zones which have an impact on the onset and the sustaining of MCSs: (i) the seasonal migration of the intertropical convergence zone (ITCZ), (ii) the GG across the northern coastline, and finally (iii) the continent. These contributions of moisture fluxes coincide with oceanic warming off Northeast Brazil and the northern coast of the GG both two days before and the day of extreme rainfall events. The ocean contributes to moisten the atmosphere, and therefore to supply and sustain the MCSs during their lifecycle.

Land subsidence studies in the Godavari Delta regions of the East coast of India using ALOS and Sentinel 1 data

Subsidence in coastal deltas is a challenging issue globally, influenced by both climate and anthropogenic pressures. Owing to its rich economic value, the Godavari Delta on the east coast of India attracts the human population and is therefore a hub of developmental activities. We quantified the line of sight (LOS) rate of land deformation in the Godavari Delta, India, for two different periods using the time series interferometric analysis of Advanced Land Observing Satellite Phase Arrayed L-band Synthetic Aperture Radar (ALOS PALSAR) (2007–2011) and C-band Sentinel-1A (2017–2020) datasets. This approach was based on the Small Baseline Subset (SBAS) algorithm, which constructed 76 (ALOS) and 333 (Sentinel-1A) pairs of interferograms. The results indicated that the majority of deltas had varying LOS deformation rates in both periods. The southern and northern coastline of the deltas showed subsidence (-10 to -20 mm/yr) and uplift (5 mm to 7 mm/yr), respectively, from 2007 to 2011. The uplift (11 mm/yr) during 2017–2020 was attributed to coastal erosion and accretion during the study period. Statistical analyses showed that the majority of the coastline experienced erosion from 2006 to 2011, ranging from 0 ‐30 m/yr. Conversely, during 2017–2019, accretion ranging from 0-30 m/yr was dominant. The Kakinada spit has recently experienced an uplift of 8 mm/yr. Many factors contributing to deformation, such as groundwater fluctuations, rainfall, land use and land cover (LULC) changes, and water quality, were explored. Groundwater level variations were strongly correlated with the rate of deformation. A direct relationship was also observed between water recharge through rainfall and the ground deformation rate. The subsidence rate was estimated as 0 to ‐8 mm/yr from 2007-2011 and -10 to -20 mm/yr for 2017–2020 in the Godavari Delta. Increased urban areas and land conversion from the LULC analysis were the causative factors of subsidence in this region. Thus, the Godavari Delta will become highly vulnerable, as the region has shown various LOS deformation rates. Studies on land subsidence are highly relevant for effective coastal management planning and management.

Vulnerability in the Java northen region in association with earthquake sources of tectonic origin

While threats from the subduction zone off the Java south coast remain persistent, potential sources of a tectonic earthquake centered in the Java northern areas come into play. Despite their enigmatic presence and a clear shift of the sources from the mainland to the north from hypocentre relocation studies, this poses a danger to the community in the Java northern coastlines, increasing vulnerability to earthquake and tsunami hazards. The main aim of this study is thus to evaluate seismic hazards and corresponding analysis, hence assessing vulnerability with respect to the presence of active faults in the northern regions. The methods used here included a-value and b-value calculations inferred from seismogenic zonation made available for the study area and source mechanism determination derived from seismic inversion for two recent events recorded at the Java Sea. The results revealed that the a-value reached 8.55 in Zone 1, reflecting a high seismicity rate over the northern areas of West Java and Banten provinces, and the b-value was about 0.8 in Central Java and East Java, implying a relatively high-stress tectonic regime. The moment tensor solutions yielded sizes M w 6.7 at a depth of 539 km and M w 7.0 at a depth of 594 km with a major double-couple component for the normal faulting types of mechanism, consistent with reference. The results suggest the significance of awareness of seismic threats possible to occur in the Java northern regions; hence more investigations into detailed seismicity in the regions of interest for future research direction.

The Avignon Chart (c. 1300–c. 1310): An Early Attempt to Represent the Northern Regions of Europe on a Nautical Chart

ABSTRACT The Avignon chart, which came to light in 2002, is one of the earliest surviving charts of the Mediterranean area. Despite its fragmentary nature and damage from reuse as a book cover in the sixteenth century, its precocity alone—it is thought to date from between c. 1300 and c. 1310, following only the Pisane (c. 1270) and the Cortona (c. 1300) charts—would be enough to ensure its importance. Researches to date, however, underline its particular significance in the history of medieval chart making. Pending further, multidisciplinary research, the present article draws attention to the main characteristics of the Avignon chart and highlights some of the enigmas of its construction, such as the way the chartmaker manipulated the orientation of the Iberian Peninsula in order to create space at the top to show, for the first time, the northern coastline of mainland Europe as far as the North and Baltic seas. The anonymous creator also constructed a grid to ensure the correct alignment of Britain, whose detailed configuration points to the use of local information among the available geographical sources for, and cultural knowledge about, the island.

GNSS land subsidence observations along the northern coastline of Java, Indonesia

Land subsidence in cities along the northern coastline of Java has been at a worrying level. Monitoring efforts using geodetic data reveal that Jakarta, Pekalongan, Semarang, and Demak subside at least ~9x faster than the present-day rate of global sea level rise, which affects the cities’ future urban viability. In this study, we publish a time series of the precise 3D displacements observed by twenty continuous Global Navigation Satellite System (GNSS) stations between 2010 and 2021. These are the first open-to-the-public and rigorously processed GNSS datasets that are useful for accurately quantifying land subsidence in the densely populated sinking cities in Java. The data also provides a way to tie other geodetic observations, such as Interferometric Synthetic Aperture Radar (InSAR), to a global reference frame in an attempt to build worldwide observations of coastal land subsidence.

Investigating the potential for a blue carbon economy on Australia’s northern coastline

The term ‘Blue Carbon’ (BC) recognises the ability of mangroves, saltmarshes, and seagrasses to capture and store carbon in their soils and biomass. Given their anoxic sediment, BC ecosystems can sequester up to as much as four times more carbon per hectare, and store it 30–50 times faster, than terrestrial forests. Australia has some of the world’s largest BC storage capacity, with 5–11% of global BC soil stocks and 2–7% of annual BC sequestration, based on available global estimate. Evidence indicates that mangrove and saltmarsh degradation from cyclone damage, feral damage and disease, is occurring throughout the Northern Territory (NT). This is a growing issue with feral animal populations degrading Indigenous lands and areas of conservation significance. This cumulative pressure on BC habitat means that northern Australia is uniquely positioned to expand BC methods to also account for protection and restoration of degraded coastal habitats including freshwater wetlands that have been damaged by non-native feral animals. Researchers from Charles Darwin University (CDU), University of Queensland (UQ), and the Northern Australian Indigenous Land and Sea Management Alliance Ltd (NAILSMA) recently worked to explore the opportunity and potential for economically viable BC methods in the NT. The study had a particular focus on Aboriginal Land gazetted under the Aboriginal Land Rights (NT) Act (1976) (Cth). We present the research outcomes and identify the pathway to focused research on BC stores and tailored methods for generating Australian Carbon Credit Units (ACCUs) and potentially biodiversity credits, in the NT.

Landfilling as individual adaptation for coastal flooding (Rob) countermeasures in North Central Java

The northern coastline of Central Java is vulnerable to coastal floods. In recent years, the area impacted by coastal flooding on the northern shore of Central Java has grown and encroached further onto the mainland. This precipitated the “sinking” of Central Java’s northern coast. The deterioration of the north shore of Central Java has a social and economic impact on the local community. Every year floods along the northern shore of Central Java cause growing property losses, particularly for the region’s residents. This forces the local community if they wish to continue living in the area, to adapt to the severe conditions in their immediate environment. Each member of the local community undertakes the adaptation process of filling the soil to raise the elevation of their home and the infrastructure surrounding it. This study demonstrates that using landfilling to elevate the base elevation of dwellings and road infrastructure is a successful adaptation technique; nevertheless, it will incur large expenses for the people, as the landfilling process would need to be repeated frequently due to sea level rise.

Trooping the (School) Colour

Trooping the (School) Colour

Migratory movements and foraging grounds of endangered green sea turtles in South China Sea based on satellite telemetry during fishing moratorium

The insights gained from individual tracking can improve the conservation of released young green sea turtles by providing detailed data on migration route, feeding place and habitat distribution. During the fishing moratorium from May 1 to August 16 in 2021, we used satellites to track 6 juvenile green sea turtles released from China’s Huidong Sea Turtle Nature Reserve, and located and reconstructed their migration routes and foraging sea areas. The tracking data shows that the longest tracking time is 91 days, the shortest time is 10 days, and the total tracking time is 213 days, of which three (50%) obtained tracking data for more than one month, and the total movement distances (statistics LC3-LCB) ranges from 124 to 4627 km, while the accurate movement distances (counted by dot pitch above LC0) ranged from 39.5-2331 km. The average daily movement distances ranges from 3.95 to 51.4 km, and the average speed varies between 0.16 to 2.14 km/h. The green turtles released from the China Turtle Bay migrate along the northern coastline of the South China Sea or go straight to the South China Sea. After a month or so, they migrate from Huidong Turtle Bay to Hainan Lingao, Beibu Gulf and Xisha Islands. The northern coast of the South China Sea is one of the migration routes of green sea turtles. Beibu Bay, Zhanjiang Port, Daya Bay, Red Bay, Nan’ao Island, Zhelin Bay and Xisha Islands are important foraging places for green sea turtles. The protection of migration routes and important foraging grounds is one of the key measures to protect sea turtles.

Sosialisasi Pemanfaatan Sampah Dan Penanaman Pohon Mangrove Desa Laulalang Kabupaten Tolitoli

The importance of maintaining a clean and healthy environment is necessary to develop a character education program "Love the Environment" for the residents of Laulalang Village. This program must also teach them how to take care of nature to protect them once again from the dangers of coastal abrasion through a greening program. This community service aims to achieve a green economy in the government system of Laulalang Village which targets the village community, especially housewives, In addition to being able to help the household economy, teenagers are also aware of the environment for the future. This program was implemented in Laulalang Village, North Tolitoli District, Tolitoli. It consists of several series of activities including socialization on waste utilization, and a mangrove tree planting program. The series of activities were carried out over two days. The result of this activity is that the community can recycle or classify types of waste that can be resold so that it has new economic value, where everything can have economic value if it is managed properly and appropriately, so it does not pollute the environment which can be detrimental to all. Then the planting of mangrove trees to create new environmental ecosystem conditions to grow and develop again along the northern coastline of Laulalang Village, with the hope that it will create a new network, a future network for Sulawesi's marine ecosystems, followed by an advanced generation who are aware of the environment for the future come.

Landfast sea ice break out patterns in the northern Bering Sea observed from C-band Synthetic Aperture Radar

Arctic sea ice is declining in areal extent and seasonal duration, affecting stable landfast sea ice regimes. These landfast ice regimes are vital platforms for local indigenous subsistence hunters and epontic primary production species supporting local and regional food webs. Under changing thermodynamic and mechanical stresses, landfast ice can become more prone to break out events - unexpected mid-season detachments from the coastline. However, the prevalence of break out events in the landfast ice annual cycle on an interannual and decadal basis is generally understudied. Here, we detect and quantify landfast ice break-out events at St. Lawrence Island in the Northern Bering Sea. We accomplished this using C-band Synthetic Aperture Radar (SAR) imagery to detect landfast ice cover. We also advanced a geospatial analysis method to identify break-out events and distinguish such occurrences from end-of-season breakups. Results reveal that 35 break-outs occurred across four sections of the St. Lawrence Island coastline from 1996 − 2019, with 74 % of break-outs occurring on the northern coastlines. Break-outs generally occurred during annual cycles with higher than average landfast ice cover. During the break-out events, maximum temperatures seldom exceed conditions promoting melt, whereas wind speeds are, on average, 2 m/s faster compared to end-of-season breakup events. However, additional datasets are needed to understand better the influence of tidal amplitude and ocean currents on detected break-out occurrence and location. Our study provides the basis for future research to understand break-out events in landfast ice annual cycles at fine spatial scales unavailable in existing sea ice datasets.

A pre-Columbian galvanic technique able to explain the gilding of copper in northern Peru

Around 150 BCE and 700 CE, pre-Columbian goldsmiths in the Peruvian northern coastline developed a method for gilding copper. The characteristics of the resulting pieces are substantially different from those obtained by hammering, embossing, and casting. We discuss two electrochemical gilding methods that were possibly developed by pre-Columbian goldsmiths. The first method consists of electrochemical replacement where copper is immersed in a solution containing dissolved gold. The second method utilizes the same solution but includes pyrite to form a galvanic cell with copper as the cathode and pyrite as the anode. Characterizations via X-ray fluorescence (XRF) and Scanning electron microscopy with energy dispersion spectroscopy (SEM-EDX) allowed a comparison of the results of the two methods with archaeological samples. The electrochemical replacement method does not reach thicknesses observed in archeological samples and delivers irregular gilding due to the formation of anodic spots on copper. Meanwhile, including pyrite as an anode in the electrochemical cell leads to a more homogeneous deposition of gold with layer thicknesses similar to those found in archaeological samples. This work contributes to understanding pre-Columbian techniques lost before the Inca Empire.