Search Results (21)

Marine biodiversity is of critical importance to global ecosystems. The Indo-Pacific Convergence Zone (IPCZ), a global marine biodiversity hotspot, faces escalating threats from human activities and climate change. This underscores the pressing need to develop effective conservation strategies for marine biodiversity in the IPCZ. This study integrates spatial analysis of ecological sensitivity (coral reefs, mangroves, and seagrass) and anthropogenic pressures (shipping/fishing intensity) to identify biodiversity hotspots and conservation gaps. Using datasets from UNEP-WCMC, OBIS, and Global Fishing Watch, we applied GIS-based multi-criteria evaluation to 5408 grid cells (0.5° resolution) across the IPCZ. Results revealed that 14.7% of the study area constitutes biodiversity hotspots, primarily in coastal Philippines, Indonesia’s Lesser Sunda Islands, and northern Australia. However, only 6% of the IPCZ is currently protected, with merely 13.88% of hotspots overlapping existing marine protected areas (MPAs). Anthropogenic pressure hotspots (e.g., Malacca Strait) showed limited spatial overlap with biodiversity hotspots, suggesting species displacement from high-disturbance zones. Priority conservation areas were delineated by balancing ecological significance and economic activity conflicts. We propose targeted strategies, including buffer zones, seasonal no-take areas, and green shipping technologies, to reconcile conservation with sustainable development. This framework provides actionable insights for enhancing MPA networks in biogeographic transition zones. Full article

This paper examines hybrid threats to maritime transportation systems and their governance responses; focusing on the congested Straits of Malacca and Singapore (SOMS) as an illustrative case study. The methodology combines secondary sources with primary data from 42 expert interviews, a 28 respondent survey, and two maritime security roundtables. Key findings were that ships’ critical systems are increasingly interconnected, yet aging IT infrastructure and minimal cybersecurity awareness among crews heighten risks. Meanwhile, regional terrorist groups have previously targeted shipping and shown considerable skill in exploiting online tools, aligning with broader calls for jihadist violence. Furthermore, opportunistic piracy persists in the SOMS with the potential to disrupt shipping. Experts confirmed that maritime cybersecurity lags behind other critical infrastructure sectors and needs updated governance. Initial International Maritime Organization (IMO) guidelines lack specificity but revisions and updated IMO guidance are in process, while Port state implementation of maritime cybersecurity standards varies. Crucially, information sharing remains inadequate, even as recorded attacks increase. Findings underscore that although major hybrid incidents have not occurred, simulations and threat actors’ capabilities demonstrate potential for catastrophic collisions or cascading disruption in congested waterways. Mitigating factors like redundancy and crew training are deficient currently. Some alignment between SOMS states on maritime security cooperation exists, but not on cyber threats specifically. Key recommendations include an anonymous cyber attack reporting system, reinforced training and shipboard systems, and consolidated regional frameworks. Until these priorities are addressed, the analysis concludes that hybrid vulnerabilities in this vital global chokepoint remain a serious concern. Full article

The significance of international maritime chokepoints and the exploration of their safety and security are intricately linked to the expansion of the maritime economy, the maintenance of political and social stability, and the safeguarding of state interests. Limited efforts have been dedicated to comprehensively assessing the extent of chokepoints’ influence or establishing a global ranking of their importance using dependable maritime data. In light of the growing significance of oceans and seas in the realms of economy and society, there is a pressing need to afford heightened attention to the importance of chokepoints. In this paper, 15 critical chokepoints from around the world are studied, and the method of Location Quotient is used to calculate the influence of their radiation range utilizing the Automatic Identification System (AIS); this study charts the worldwide spatial and temporal dimensions of maritime transport spanning from 2012 to 2022. The conclusion of this study reveals the following key findings: (1) Maritime shipping trajectories exhibit fluctuating growth over time, with traffic hotspots predominantly located in continental border zones, gradually decreasing from the equator toward the poles; (2) The regions with active maritime traffic do not exhibit a positive correlation with the hotspots; instead, there is a pattern of “strong in the north, weak in the south, strong in the east, weak in the west”; (3) The Strait of Gibraltar and the Strait of Malacca are identified as the globally most strategically valuable straits for maritime shipping; (4) There is significant variation in the influence range of strategic passages, and countries with mutual dependencies may have competitive relationships. Full article

Maritime transportation is vital for the movement of cargo between different continents and distant locations but can be disrupted by the frequent occurrence of pirate attacks. Based on the pirate attacks from July 1994 to December 2019, a spatial analysis of pirate attacks using a Geographic Information System (GIS) was conducted in the present study using the data available for tankers, dry bulk carriers, container vessels, general cargo vessels, and tugs. The adoption of the kernel density analysis was intended to identify the spatial pattern of global pirate attacks. The research results demonstrated that the pirate attacks showed a clustering pattern and were mostly associated with areas experiencing economic depression, a high unemployment rate, and social unrest. Accordingly, spatiotemporal hot spot analysis was carried out to recognize the changing directions of cold spots and hot spots over a period of time. The waters off Somalia, the Strait of Malacca, the Philippines, the Bay of Bengal, the Gulf of Guinea, and the northwest of South America were found to be the common locations of pirate attacks. The cold and hot spots of pirate attacks on the three key vessel types, including tankers, dry bulk carriers, and container vessels, were found to be similar. When considering the same area, the trends of cold and hot spots of different vessel types being attacked were substantially different. This study can provide a useful guideline for the International Maritime Organization and other relevant organizations in the world to design and implement targeted strategies to combat and mitigate pirate attacks. Additionally, the introduction of a GIS may help to envision the spatial and temporal distribution of pirate attacks and to explore the characteristics of pirate behaviors at sea and the patterns of piracy. Full article

In the maritime industry, optimizing vessel fuel oil consumption is crucial for improving energy efficiency and reducing shipping emissions. However, effectively utilizing operational data to advance performance monitoring and optimization remains a challenge. An XGBoost Regressor model was developed using a comprehensive dataset, delivering strong predictive performance (R² = 0.95, MAE = 10.78 kg/h). This predictive model considers operational (controllable) and environmental (uncontrollable) variables, offering insights into complex FOC factors. To enhance interpretability, SHAP analysis is employed, revealing ‘Average Draught (Aft and Fore)’ as the key controllable factor and emphasizing ‘Relative Wind Speed’ as the dominant uncontrollable factor impacting vessel FOC. This research extends to further analysis of the extremely high FOC point, identifying patterns in the Strait of Malacca and the South China Sea. These findings provide region-specific insights, guiding energy efficiency improvement, operational strategy refinement, and sea resistance mitigation. In summary, our study introduces a groundbreaking framework leveraging machine learning and SHAP analysis to advance FOC understanding and enhance maritime decision making, contributing significantly to energy efficiency and operational strategies—a substantial contribution to a responsible shipping performance assessment under tightening regulations. Full article

The Maritime Silk Road (MSR) is an important channel for maritime trade between China and other countries in the world. Maritime piracy has brought huge security risks to ships’ navigation and has seriously threatened the lives and property of crew members. To reduce the likelihood of attacks from pirates, it is necessary to study the risk to a ship exposed to attacks from pirates on the MSR. Firstly, risk factors were established from three risk component categories (hazard, mitigation capacity, and vulnerability and exposure) and the risk index system of piracy and armed robbery events was founded. Secondly, the dynamic Bayesian network (DBN) method was introduced to establish a pirate attack risk assessment model ad to conduct a quantitative analysis of the process risk of a ship being attacked by pirates. Finally, combined with the scene data of the MSR, the process risk of a ship being attacked by pirates was modeled and applied as an example. The results showed that the overall risk of a ship being attacked by pirates is the lowest in July and the highest in March. In the whole route, when the ship was in the Gulf of Guinea, the Gulf of Aden–Arabian Sea, and the Strait of Malacca, the risk of pirate attack was the highest. This dynamic network model can effectively analyze the level of risk of pirate attacks on ships, providing a reference for the safety decision-making of ships on ocean routes. Full article

Plastics account for 60–80% of marine debris worldwide, and, in 2021, Malaysia was the 28th largest plastic polluter in the world. In light of this finding, the Malaysian government has launched the Roadmap Towards Zero Single-Use Plastics 2018–2030 and the Plastics Sustainability Roadmap 2021–2030 to reduce plastic pollution and implement a circular economy for Malaysia. A comprehensive database of the status of plastic pollution in Malaysia is needed to achieve this target. This study aims to record the presence of macro- (>2.5 cm) and mesoplastic (0.5–2.5 cm) debris at selected beaches in the northern Strait of Malacca. All study sites are publicly accessible beaches (Pulau Songsong, Teluk Aling, and Pulau Gazumbo) except Pulau Lembu, which is in a Marine Protected Area (MPA). The debris was collected from predetermined transects on the beach and categorised according to its form and economic market segments in Malaysia. Most of the macro- (53–75% of total mass) and mesoplastics (52–80% of the total number) were accumulated in the backshore area. Public beaches such as Pulau Gazumbo and Pulau Songsong recorded the highest abundance of macroplastics, with 7.32 g/m² and 9.77 g/m², respectively. Teluk Aling recorded the lowest abundance of macroplastics (3.58 g/m²) but the highest in mesoplastics (0.55 items/m²). Most of the macroplastics found were packaging plastics such as plastic bottles, containers, and polystyrene foam debris. Although Pulau Lembu is an MPA, the amount of macroplastics found was considerably high (7.17 g/m²). Based on the beach cleanliness index, Pulau Gazumbo (−3.99) was the dirtiest site, followed by Pulau Lembu (−2.92) and Pulau Songsong (−2.85), while Teluk Aling (−1.63) was the cleanest site, which can explain the amount of macroplastic debris found. However, all the study sites’ cleanliness may not be ideal, as the indexes were less than zero due to the low availability of waste bins and insufficient frequency of beach cleaning. This may not be able to curb the effects of high anthropogenic activities conducted in addition to uncontrollable natural factors. Full article

The sea level trend in the equatorial Malacca Strait is a significant issue that needs to be reviewed since it is an area of interest. Assessing its future impact on estuarine tidal characteristics is worth studying because it relates to the potency of coastal damages. This study aimed to discuss the relationship between sea level variations and anomalies and their possible triggering factors and to estimate the future impacts on the tidal properties in the estuarine zone. Tide gauge and altimetry data in the Tanjong Pagar site were used to assess the sea level trends over 27 years of observation (from 1992 to 2019). Both altimetry and tide gauge data showed an upward trend, with 0.24 cm/year and 0.39 cm/year, respectively. Due to the near-equatorial area of interest, sea level variability is more synchronized with ENSO rather than IOD. At some points, ENSO shapes the sea level fluctuation, with an R² of less than 10%. For specific periods, the coupling effects between MJO and La Niña may trigger higher evaporation in the maritime continent, triggering increasing sea levels. Of particular concern, among the other assessed factors, the zonal currents and winds (wind-driven currents) are strongly correlated with sea level variations, primarily during the NE monsoon and the second transitional periods, with a determination coefficient of about 18–36%. As a result of sea level rises, it is estimated that tidal constituent amplitudes will increase by about 8.9% and 18.3% in 2050 and 2100, respectively. The increase in tidal range will possibly relate to the tidal bore passage in the Kampar estuary. Therefore, more advanced hydrodynamic modeling is necessary to determine the impact of sea level rises on tidal bore generation. Full article

Absolute sea-level rise has become an important topic globally due to climate change. In addition, relative sea-level rise due to the vertical land motion in coastal areas can have a big societal impact. Vertical land motion (VLM) in Southeast Asia includes a tectonically induced component: uplift and subsidence in plate boundary zones where both Peninsular and East Malaysia are located. In this paper, the relative sea-level trends and (seismic cycle-induced) temporal changes across Malaysia were investigated. To do so, the data (1984–2019) from 21 tide gauges were analyzed, along with a subset (1994–2021) of nearby Malaysian GNSS stations. Changes in absolute sea level (ASL) at these locations (1992–2021) were also estimated from satellite altimetry data. As a first for Peninsular and East Malaysia, the combination ASL minus VLM was robustly used to validate relative sea-level rise from tide-gauge data and provide relative sea-level trend estimates based on a common data period of 25+ years. A good match between both the remote and in situ sea-level rise estimations was observed, especially for Peninsular Malaysia (differences < 1 mm/year), when split trends were estimated from the tide gauges and GNSS time series to distinguish between the different VLM regimes that exist due to the 2004 Sumatra–Andaman megathrust earthquake. As in the south of Thailand, post-seismic-induced negative VLM has increased relative sea-level rise by 2–3 mm/year along the Andaman Sea and Malacca Strait coastlines since 2005. For East Malaysia, the validation shows higher differences (bias of 2–3 mm/year), but this poorer match is significantly improved by either not including data after 1 January 2014 or applying a generic jump to all East Malay tide gauges from that date onwards. Overall, the present relative sea-level trends range from 4 to 6 mm/year for Malaysia with a few regions showing up to 9 mm/year due to human-induced land subsidence. Full article

The Peninsular Malaysia Geodetic Vertical Datum 2000 (PMGVD2000) inherited several deficiencies due to offsets between local datums used, levelling error propagations, land subsidence, sea level rise, and sea level slopes along the southern half of the Malacca Strait on the west coast and the South China Sea in the east coast of the Peninsular relative to the Port Klang (PTK) datum point. To cater for a more reliable elevation-based assessment of both sea level rise and coastal flooding exposure, a new epoch-based height reference system PMGVD2022 has been developed. We have undertaken the processing of more than 30 years of sea level data from twelve tide gauge (TG) stations along the Peninsular Malaysia coast for the determination of the relative mean sea level (RMSL) at epoch 2022.0 with their respective trends and incorporates the quantification of the local vertical land motion (VLM) impact. PMGVD2022 is based on a new gravimetric geoid (PMGeoid2022) fitted to the RMSL at PTK. The orthometric height is realised through the GNSS levelling concept H = h^GNSS–N^fit_PTK–N_RMDT, where N_RMDT is a constant offset due to the relative mean dynamic ocean topography (RMDT) between the fitted geoid at PTK and the local MSL datums along the Peninsular Malaysia coast. PMGVD2022 will become a single height reference system with absolute accuracies of better than ±3 cm and ±10 cm across most of the land/coastal area and the continental shelf of Peninsular Malaysia, respectively. Full article

Global warming trends and the rapid reduction of summer Arctic sea ice extent have increased the feasibility of transarctic transport. How the process of glacier melting affects the existing containerized sea–rail shipping network and container flow assignment has become a challenging economic and policy issue. This paper first examines the meteorological influences on glacier melting and the assignment of container flow over the existing sea–rail network. Then, a three-layer simulation framework is constructed, with the upper layer simulating glacier melting based on the raster grid, the middle layer combining a grid and topology analysis to simulate the evolution of the global sea–rail network and the lower layer establishing a concave cost network flow model to simulate the container flow assignment. Finally, we use MicroCity to achieve the dynamic optimization and simulation of global container flow assignment, solving the large-scale sea–rail shipping network traffic assignment problem. The simulation results show that the proposed model and solution algorithm are feasible and effective, revealing the variation of container flow assignment in the global sea–rail shipping network under different Arctic ice melting scenarios. For instance, in the summer of 2050, the Arctic routes will share the global container flows, resulting in a significant reduction of container flows in the Malacca Strait, Suez Canal and Panama Canal. Full article

Previous examination of the mitochondrial NADH2 gene and morphological characteristics led to the resurrection of Scoliodon macrorhynchos as a second valid species in the genus, in addition to S. laticaudus. This study applied an integrated taxonomic approach to revisit the classification of the genus Scoliodon based on new materials from the Malaysian Peninsula, Malaysian Borneo and Eastern Bay of Bengal. Mitochondrial DNA data suggested the possibility of three species of Scoliodon in the Indo-West Pacific, while the nuclear DNA data showed partially concordant results with a monophyletic clade of S. macrorhynchos and paraphyletic clades of S. laticaudus and S. cf. laticaudus from the Malacca Strait. Morphological, meristic and dental characteristics overlapped between the three putative species. Collective molecular and morphological evidence suggested that the differences that exist among the non-sympatric species of Scoliodon are consistent with isolation by distance, and Scoliodon macrorhynchos remains as a valid species, while S. cf. laticaudus is assigned as S. laticaudus. The Malacca Strait acts as a spatial delineator in separating the Pacific S. macrorhynchos (including South China Sea) from the Northern Indian Ocean S. laticaudus. Future taxonomic work should focus on clarifying the taxonomic status of Scoliodon from the Indonesian waters. Full article

A broad-scale comparative phylogeographic and phylogenetic study of pennah croakers, mainly Pennahia anea, P. macrocephalus, and P. ovata was conducted to elucidate the mechanisms that may have driven the diversification of marine organisms in Southeast Asian waters. A total of 316 individuals from the three species, and an additional eight and six individuals of P. argentata and P. pawak were employed in this study. Two genetically divergent lineages each of P. argentata and P. anea (lineages L1 and L2) were respectively detected from the analyses based on mitochondrial cytochrome b gene data. Historical biogeography analysis with a multi-gene dataset revealed that Pennahia species most likely originated in the South China Sea and expanded into the eastern Indian Ocean, East China Sea, and northwestern Pacific Ocean through three separate range expansions. The main diversifications of Pennahia species occurred during Miocene and Pliocene periods, and the occurrences of lineage divergences within P. anea and P. argentata were during the Pleistocene, likely as a consequence of cyclical glaciations. The population expansions that occurred after the sea level rise might be the reason for the population homogeneity observed in P. macrocephalus and most P. anea L2 South China Sea populations. The structure observed between the two populations of P. ovata, and the restricted distributions of P. anea lineage L1 and P. ovata in the eastern Indian Ocean, might have been hampered by the northward flowing ocean current at the Malacca Strait and by the distribution of coral reefs or rocky bottoms. While our results support S. Ekman’s center-of-origin hypothesis taking place in the South China Sea, the Malacca Strait serving as the center of overlap is a supplementary postulation for explaining the present-day high diversity of pennah croakers centered in these waters. Full article

The establishment of maritime safety and security is an important concern. Ship position prediction for maritime situational awareness (MSA), as a critical aspect of maritime safety and security, requires a longer time interval than collision avoidance and maritime traffic monitoring. However, previous studies focused mainly on shorter time-interval predictions ranging from 30 min to 10 h. A longer time-interval ship position prediction is required not only for MSA, but also for efficient allocation of ships by shipping companies in accordance with global freight demand. This study used an end-to-end tracking method that inputs the previous position of a vessel to a trained deep learning model to predict its next position with an average 24-h interval. An AIS dataset with a long-time-interval distribution in a nine-year timespan for capesize bulk carriers worldwide was used. In the first experiment, a deep learning model of the Indian Ocean was examined. Subsequently, the model performance was compared for six different oceans and six primary maritime chokepoints to investigate the influence of each area. In the third experiment, a sample location within the Malacca Strait area was selected, and the number of ships was counted daily. The results indicate that the ship position can be predicted accurately with an average time interval of 24 h using deep learning systems with AIS data. Full article

Synthetic aperture radar (SAR) is an important means to observe the sea surface wind field. Sentinel-1 and GF-3 are located on orbit SAR satellites, but the SAR data quality of these two satellites has not been evaluated and compared at present. This paper mainly studies the data quality of Sentinel-1 and GF-3 SAR satellites used in wind field inversion. In this study, Sentinel-1 SAR data and GF-3 SAR data located in Malacca Strait, Hormuz Strait and the east and west coasts of the United States are selected to invert wind fields using the C-band model 5.N (CMOD5.N). Compared with reanalysis data called ERA5, the root mean squared error (RMSE) of the Sentinel-1 inversion results is 1.66 m/s, 1.37 m/s and 1.49 m/s in three intervals of 0~5 m/s, 5~10 m/s and above 10 m/s, respectively; the RMSE of GF-3 inversion results is 1.63 m/s, 1.45 m/s and 1.87 m/s in three intervals of 0~5 m/s, 5~10 m/s and above 10 m/s, respectively. Based on the data of Sentinel-1 and GF-3 located on the east and west coasts of the United States, CMOD5.N is used to invert the wind field. Compared with the buoy data, the RMSE of the Sentinel-1 inversion results is 1.20 m/s, and the RMSE of the GF-3 inversion results is 1.48 m/s. The results show that both Sentinel-1 SAR data and GF-3 SAR data are suitable for wind field inversion, but the wind field inverted by Sentinel-1 SAR data is slightly better than GF-3 SAR data. When applied to wind field inversion, the data quality of Sentinel-1 SAR is slightly better than the data quality of GF-3 SAR. The SAR data quality of GF-3 has achieved a world-leading level. Full article