Hampik Maroukian, Evangelos Spyrou, Sofia Tsiatoura, Maria Tzouxanioti, Niki Evelpidou
{"title":"Sea Level Rise and the Future of Tombolos: The Case of Greece","authors":"Hampik Maroukian, Evangelos Spyrou, Sofia Tsiatoura, Maria Tzouxanioti, Niki Evelpidou","doi":"10.3390/jmse12091578","DOIUrl":"https://doi.org/10.3390/jmse12091578","url":null,"abstract":"Tombolos are ephemeral coastal landforms, which may form and disappear over short geological time periods. Thus, they are susceptible to marine processes. During the last decades, however, climate change and the subsequent sea level rise seems to have affected a large part of the world’s coastlines. Tombolos are particularly prone to the imminent sea level rise. Many tombolos globally may disappear in the coming decades. Our work aims to quantify the susceptibility of the tombolos along the Greek coastline in relationship to the sea level rise. We mapped all Greek tombolos and created an online (and public) geodata base. For each tombolo, we measured its primary physiographical characteristics (e.g., length and width), and also its height above sea level. Based on that, we applied two scenarios proposed by the IPCC concerning the future sea level rise (RCP 2.6 and RCP 8.5), in order to check to what extent the Greek tombolos may disappear or face extreme erosion in the next few decades. Our results indicate that more than half of the Greek tombolos will be fully flooded and disappear in 100 years even under the optimistic scenario. Even those that remain will still face severe erosion problems.","PeriodicalId":16168,"journal":{"name":"Journal of Marine Science and Engineering","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Igor V. Miskevich, Alexey S. Lokhov, Dmitry S. Moseev, Ekaterina I. Kotova
{"title":"Polymetallic Ore Mining Impact Assessment on the Benthic Hydrobiocenosis of the Small Estuaries on the Arctic Islands","authors":"Igor V. Miskevich, Alexey S. Lokhov, Dmitry S. Moseev, Ekaterina I. Kotova","doi":"10.3390/jmse12091570","DOIUrl":"https://doi.org/10.3390/jmse12091570","url":null,"abstract":"The results of studies on the content of aluminum and heavy metals in benthic sediments and algae in the estuaries of the Arctic island Vaygach are presented. This island is located on the Barents and Kara Sea border, and it is part of the Pay-Khoi ridge which can be called a “continuation” of the Ural Mountains to the north. The observations were conducted in Krasnaya and Varkulyakha Rivers located in the island’s southern part and flow into the Yugorsky Shar Strait. Krasnaya River is located near a polymetallic ore deposit, which was developed in 1931–1934. Reconnaissance fieldwork was carried out in the river estuaries through measurements of salinity and water level. Measurements of the mass concentration of elements in the studied samples of sediments and algae were carried out by atomic emission spectrometry. The preparation of plant samples was by microwave decomposition, and that for samples of bottom sediments was carried out by acid decomposition in an open manner. The obtained concentration samples were compared using “Tukey exploratory data analysis (EDA)”. The presence of anomalies in the high content of copper, manganese, and zinc in filamentous algae at the control site in the Krasnaya River estuary was revealed. For some elements, the enrichment index was calculated relative to the upper part of the earth’s crust content. It is assumed that the occurrence of this situation is due to the long-term consequences of mining polymetallic ores. The accumulation of metals in river estuaries may be related to the observed warming of the climate in the western sector of the Arctic region.","PeriodicalId":16168,"journal":{"name":"Journal of Marine Science and Engineering","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142227316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Gradient Boosted Trees and Denoising Autoencoder to Correct Numerical Wave Forecasts","authors":"Ivan Yanchin, C. Guedes Soares","doi":"10.3390/jmse12091573","DOIUrl":"https://doi.org/10.3390/jmse12091573","url":null,"abstract":"This paper is dedicated to correcting the WAM/ICON numerical wave model predictions by reducing the residue between the model’s predictions and the actual buoy observations. The two parameters used in this paper are significant wave height and wind speed. The paper proposes two machine learning models to solve this task. Both models are multioutput models and correct the significant wave height and wind speed simultaneously. The first machine learning model is based on gradient boosted trees, which is trained to predict the residue between the model’s forecasts and the actual buoy observations using the other parameters predicted by the numerical model as inputs. This paper demonstrates that this model can significantly reduce errors for all used geographical locations. This paper also uses SHapley Additive exPlanation values to investigate the influence that the numerically predicted wave parameters have when the machine learning model predicts the residue. To design the second model, it is assumed that the residue can be modelled as noise added to the actual values. Therefore, this paper proposes to use the denoising autoencoder to remove this noise from the numerical model’s prediction. The results demonstrate that denoising autoencoders can remove the noise for the wind speed parameter, but their performance is poor for the significant wave height. This paper provides some explanations as to why this may happen.","PeriodicalId":16168,"journal":{"name":"Journal of Marine Science and Engineering","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Method for Estimating the Distribution of Trachinotus ovatus in Marine Cages Based on Omnidirectional Scanning Sonar","authors":"Yu Hu, Jiazhen Hu, Pengqi Sun, Guohao Zhu, Jialong Sun, Qiyou Tao, Taiping Yuan, Gen Li, Guoliang Pang, Xiaohua Huang","doi":"10.3390/jmse12091571","DOIUrl":"https://doi.org/10.3390/jmse12091571","url":null,"abstract":"In order to accurately estimate the distribution of Trachinotus ovatus in marine cages, a novel method was developed using omnidirectional scanning sonar and deep-learning techniques. This method involved differentiating water layers and clustering data layer by layer to achieve precise location estimation. The approach comprised two main components: fish identification and fish clustering. Firstly, omnidirectional scanning sonar was employed to perform spiral detection within marine cages, capturing fish image data. These images were then labeled to construct a training dataset for an enhanced CS-YOLOv8s model. After training, the CS-YOLOv8s model was used to identify and locate fish within the images. Secondly, the cages were divided into water layers with depth intervals of 40 cm. The identification coordinate data for each water layer were clustered using the DBSCAN method to generate location coordinates for the fish in each layer. Finally, the coordinate data from all water layers were consolidated to determine the overall distribution of fish within the cage. This method was shown, through multiple experimental results, to effectively estimate the distribution of Trachinotus ovatus in marine cages, closely matching the distributions detected manually.","PeriodicalId":16168,"journal":{"name":"Journal of Marine Science and Engineering","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Study on the Bearing Capacity of Square Skirted Anchors with Different Mooring Points","authors":"Yandi Wang, Sa Li, Liqiang Sun, Yuxiao Ren","doi":"10.3390/jmse12091572","DOIUrl":"https://doi.org/10.3390/jmse12091572","url":null,"abstract":"Skirted anchors are often used as temporary or permanent anchoring foundations for underwater pipelines and floating platforms. A series of model tests and finite element simulations were conducted to study the bearing capacity of square skirted anchors with different mooring points. Based on the test results, two failure modes of square skirted anchors with different mooring points were analyzed. It was found that, when the mooring point was located at the top of the side skirt, the square skirted anchor was more prone to rotation and had a lower bearing capacity. The numerical method was validated by the model tests. In total, 140 numerical calculation results show that, when the mooring point position (normalized depth of mooring point) h/H = 0.5~0.75 and the load inclination angle θ = 0°~30°, the bearing performance of the square skirted anchor is optimal. As the aspect ratio of the square skirted anchor (H/B) increases from 0.25 to 2.0, the optimal mooring point position h/H moves downward from 0.5 to 0.75. The failure envelopes in the V-H loading space of the square skirted anchor were drawn, and the corresponding fitting equation was obtained.","PeriodicalId":16168,"journal":{"name":"Journal of Marine Science and Engineering","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Regional Sea Level Changes in the East China Sea from 1993 to 2020 Based on Satellite Altimetry","authors":"Lujie Xiong, Fengwei Wang, Yanping Jiao","doi":"10.3390/jmse12091552","DOIUrl":"https://doi.org/10.3390/jmse12091552","url":null,"abstract":"A comprehensive analysis was carried out to investigate the driving factors and influencing mechanisms of spatiotemporal variation of sea level at multiple scales in the East China Sea (ECS) via satellite altimetry datasets from 1993 to 2020. Based on the altimetry grid data processed by the local mean decomposition method, the spatiotemporal changes of ECS sea level are analyzed from the multi-scale perspective in terms of multi-year, seasonal, interannual, and multi-modal scales. The results revealed that the ECS regional mean sea level change rate is 3.41 ± 0.58 mm/year over the 28-year period. On the seasonal scale, the regional mean sea level change rates are 3.45 ± 0.66 mm/year, 3.35 ± 0.60 mm/year, 3.39 ± 0.71 mm/year, and 3.57 ± 0.75 mm/year, for the four seasons (i.e., spring, summer, autumn, and winter) respectively. The spatial distribution analysis showed that ECS sea level changes are most pronounced in coastal areas. The northeast sea area of Taiwan and the edge of the East China Sea shelf are important areas of mesoscale eddy activity, which have an important impact on regional sea level change. The ECS seasonal sea level change is mainly affected by monsoons, precipitation, and temperature changes. The spatial distribution analysis indicated that the impact factors, including seawater thermal expansion, monsoons, ENSO, and the Kuroshio Current, dominated the ECS seasonal sea level change. Additionally, the ENSO and Kuroshio Current collectively affect the spatial distribution characteristics. Additionally, the empirical orthogonal function was employed to analyze the three modes of ECS regional sea level change, with the first three modes contributing 26.37%, 12.32%, and 10.47%, respectively. Spatially, the first mode mainly corresponds to ENSO index, whereas the second and third modes are linked to seasonal factors, and exhibit antiphase effects. The analyzed correlations between the ECS sea level change and southern oscillation index (SOI), revealed the consistent spatial characteristics between the regions affected by ENSO and those by the Kuroshio Current.","PeriodicalId":16168,"journal":{"name":"Journal of Marine Science and Engineering","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142227317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"DNA Barcoding and Intronic-ORF Structure Analyses of Cultivated Pyropia yezoensis in China: The Genetic Impact under Climate Change","authors":"Guihua Huang, Cuicui Tian, Liangdi Wei, Chuanming Hu, Guangping Xu, Wei Zhou, Yinyin Deng","doi":"10.3390/jmse12091551","DOIUrl":"https://doi.org/10.3390/jmse12091551","url":null,"abstract":"Pyropia yezoensis is the most widely cultivated and economically important alga. Affected by climate change, the cultivation of P. yezoensis has gradually migrated to the northern coast of China, increasing from 6.8% in 2019 to 19.5% in 2023. To date, the genetic impact of northern migration on cultivation resources has not been assessed and analyzed extensively. Here, DNA barcoding (rbcL and cox1) and the presence/absence of intronic-ORFs in mitochondrial regions (rnl and cox1) were applied to investigate genetic diversity in 44 P. yezoensis specimens from 17 aquaculture farms in China, with comparisons to Korean and Japanese cultivated resources. The lower intraspecific variation was 0.31% for the cox1 gene and 0.14% for the rbcL gene, with three haplotypes, indicating that intensive selection and breeding during cultivation had narrowed the germplasm genetic variation. The intron structure of mitochondrial regions showed that the cultivated resources had 17 phenotypes, and the northern specimens shared 35.3% of genotypes with the southern specimens, indicating that the cultivated P. yezoensis is expanding its cultivation ranges through north migration. Even with lower genetic diversity, the northern area of cultivation had already developed 17.6% site-specific specimens. The genetic diversity of cultivated P. yezoensis from the Northwest Pacific is also discussed. Our work provides a preliminary framework for P. yezoensis breeding and cultivation under climate change.","PeriodicalId":16168,"journal":{"name":"Journal of Marine Science and Engineering","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Exploring Carbon Emission Reduction in Inland Port Ship Based on a Multi-Scenario Model","authors":"Chunhui Zhou, Wuao Tang, Zongyang Liu, Hongxun Huang, Liang Huang, Changshi Xiao, Lichuan Wu","doi":"10.3390/jmse12091553","DOIUrl":"https://doi.org/10.3390/jmse12091553","url":null,"abstract":"Assessing carbon emission reduction potential is vital for achieving carbon peak and neutrality in the maritime sector. In this study, we proposed a universal framework for assessing the effectiveness of different measures on carbon emission reduction from ships, including port and ship electrification (PSE), ship speed optimization (SSO), and clean fuel substitution (CFS). Firstly, the projection method of future ship traffic flows and activity levels relies on a neural network, and the ARIMA model was proposed. Then, the potential of various emission reduction measures was detailed and analyzed under different intensity scenarios. The proposed model was applied to Wuhan port, the results indicate that CFS is the most effective for long-term decarbonization, potentially achieving a carbon peak by 2025 under an aggressive scenario. For the short to medium term, PSE is favored due to technical maturity. SSO primarily delays emissions growth, making it a suitable auxiliary measure. These findings guide emission reduction strategies for ports, fostering green and sustainable shipping development.","PeriodicalId":16168,"journal":{"name":"Journal of Marine Science and Engineering","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Prescribed-Time Trajectory Tracking Control for Unmanned Surface Vessels with Prescribed Performance Considering Marine Environmental Interferences and Unmodeled Dynamics","authors":"Bowen Sui, Yiping Liu, Jianqiang Zhang, Zhong Liu, Yuanyuan Zhang","doi":"10.3390/jmse12081380","DOIUrl":"https://doi.org/10.3390/jmse12081380","url":null,"abstract":"This article investigates a prescribed-time trajectory tracking control strategy for USVs considering marine environmental interferences and unmodeled dynamics. Firstly, a fixed-time extended state observer is introduced to quickly and accurately observe the compound perturbations including ocean disturbances and unmodeled dynamics. Subsequently, a prescribed-time prescribed performance function is utilized to obtain guaranteed transient performance within a predefined time. Finally, combining the fixed-time extended state observer, dynamic surface control technique, and prescribed-time prescribed performance control, a prescribed-time prescribed performance control strategy is developed to guarantee that the tracking errors converge to a predefined performance constraint boundary within a prescribed time. The effectiveness and superiority of the presented control strategy is verified by the simulation results.","PeriodicalId":16168,"journal":{"name":"Journal of Marine Science and Engineering","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141936877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Opportunity-Maintenance-Based Scheduling Optimization for Ship-Loading Operation Systems in Coal Export Terminals","authors":"Qi Tian, Yun Peng, Xinglu Xu, Wenyuan Wang","doi":"10.3390/jmse12081377","DOIUrl":"https://doi.org/10.3390/jmse12081377","url":null,"abstract":"As important nodes of the global coal supply chain, coal export terminals bear the tasks of coal storage, processing, and handling, whose efficiency and stability are of great importance with the growing coal shipping market in recent years. However, poor working conditions of the handling equipment in the coal export terminal, together with its relatively fixed layout and poor flexibility, allow frequent equipment failures to seriously affect the ship-loading operations. To solve the problem, this paper constructs a scheduling optimization model for ship-loading operation systems considering equipment maintenance and proposes an opportunity-maintenance-based two-layer algorithm to solve the model. The upper layer aims to optimize the scheduling scheme of the ship-loading operation system under a certain maintenance plan. The lower layer of the algorithm, an opportunity-maintenance-based “equipment-level–flow-level” maintenance optimization method, determines the best equipment maintenance plan. A coal export terminal in China is employed as the case study to verify the effectiveness of the proposed method. The results show that the proposed method can reduce the average dwell time of ships at the terminal by 15.8% and save total scheduling and maintenance costs by 10.3%. This paper shows how to make full use of equipment failure historical data and integrate equipment maintenance schemes into the scheduling problem of the ship-loading operation system, which can effectively reduce the impact of equipment failures on ship-loading operations and provide decision support for coal export terminal management.","PeriodicalId":16168,"journal":{"name":"Journal of Marine Science and Engineering","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141936871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}