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Journal articles on the topic 'Bathymetric measurements'
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1
Ochałek, Agnieszka, Tomasz Lipecki, Wojciech Jaśkowski, and Mateusz Jabłoński. "Modeling and Analysis of Integrated Bathymetric and Geodetic Data for Inventory Surveys of Mining Water Reservoirs." E3S Web of Conferences 35 (2018): 04005. http://dx.doi.org/10.1051/e3sconf/20183504005.
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The significant part of the hydrography is bathymetry, which is the empirical part of it. Bathymetry is the study of underwater depth of waterways and reservoirs, and graphic presentation of measured data in form of bathymetric maps, cross-sections and three-dimensional bottom models. The bathymetric measurements are based on using Global Positioning System and devices for hydrographic measurements – an echo sounder and a side sonar scanner. In this research authors focused on introducing the case of obtaining and processing the bathymetrical data, building numerical bottom models of two post-mining reclaimed water reservoirs: Dwudniaki Lake in Wierzchosławice and flooded quarry in Zabierzów. The report includes also analysing data from still operating mining water reservoirs located in Poland to depict how bathymetry can be used in mining industry. The significant issue is an integration of bathymetrical data and geodetic data from tachymetry, terrestrial laser scanning measurements.
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Wang, Yitong, Ziyi Lu, Dihao Ma, and Zixin Yang. "The study of the direction of navigation of ships in a particular sea area." Highlights in Science, Engineering and Technology 82 (January 26, 2024): 77–84. http://dx.doi.org/10.54097/fq9fg659.
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Multibeam bathymetric system is a further development of single-beam bathymetric system, which can send and receive hundreds of beams at the same time during the working process, and carry out full-coverage bathymetric strip measurements in the smooth sea area on the seabed. In this paper, we model the coverage width and the overlap rate to further reduce the errors occurring in the measurement process, and at the same time, we design a scheme for the given data and constraints to solve the practical problems. The process analysis facilitates the practical application of multibeam bathymetry system, improves the problems of failing to achieve the full coverage of the sea area and the high overlap rate, and provides a new idea for the seabed detection of multibeam bathymetry.
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Herrmann, Joan, Lori A. Magruder, Jonathan Markel, and Christopher E. Parrish. "Assessing the Ability to Quantify Bathymetric Change over Time Using Solely Satellite-Based Measurements." Remote Sensing 14, no. 5 (2022): 1232. http://dx.doi.org/10.3390/rs14051232.
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Coastal regions are undergoing rapid change, due to natural and anthropogenic forcings. A current constraint in understanding and modeling these changes is the lack of multi-temporal bathymetric data, or recursive observations. Often, it is difficult to obtain the repeat observations needed to quantify bathymetric change over time or events. However, the recent availability of ICESat-2 bathymetric lidar creates the option to map coastal bathymetry from solely space-based measurements via satellite-derived bathymetry with multispectral imagery (IS-2/SDB). This compositional space-based bathymetric mapping technique can assess temporal change along the coasts without other remote sensing or in situ data. However, questions exist as to the accuracy of the technique relative to both quantitative uncertainties and the ability to resolve the spatial patterns of erosion and deposition in the nearshore environment, indicative of geomorphologic change. This paper addresses the concept using data from the Florida panhandle (Northern Gulf of Mexico) collected by Sentinel-2 and ICESat-2 at two epochs to assess the feasibility of using IS-2/SDB for bathymetric change detection at scientifically relevant scales, spatial resolutions and accuracies. The comparison of the satellite-only result is compared to airborne data collected at similar epochs to reveal both quantitatively and qualitatively the utility of this technique.
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Md. Mahabub Alam and Md Nuruzzaman. "Comparative analysis of interpolation methods commonly used in bathymetric data generation." World Journal of Advanced Research and Reviews 25, no. 3 (2025): 2018–29. https://doi.org/10.30574/wjarr.2025.25.3.0835.
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This research paper aims to provide a comparative analysis of interpolation methods for estimating bathymetric data. Accurate measurement of bathymetry is crucial for a variety of applications, including navigation, oceanography, and coastal management. However, due to the high cost and difficulty of acquiring bathymetric data, gaps in measurements are common. Interpolation methods are widely used to fill these gaps and estimate the depths of water at unsampled locations. In this study, we analyze the most commonly used interpolation methods, including linear, inverse distance weighting, kriging, triangulated irregular network, moving least squares, piecewise cubic Hermite interpolating polynomial, and spline interpolation. We compare and evaluate the performance of these methods using both simulated and real-world datasets. Additionally, we provide a systematic analysis of the strengths and weaknesses of each method in terms of their accuracy in estimating bathymetry. The goal of this paper is to offer a comprehensive overview of interpolation methods for bathymetric data and to assist researchers and practitioners in selecting the most suitable method for a given task and dataset.
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Mukhamedina, A. Ye, D. K. Abiyeva, and K. M. Kulebayev. "Assessment of the potential use of ICESat-2 data for bathymetric mapping of small lakes of Kazakhstan." Geography and water resources, no. 2 (June 30, 2022): 43–49. http://dx.doi.org/10.55764/2957-9856/2022-2-43-49.12.
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Lake bathymetry is of great importance for water resources management and hydrological modeling. Bathymetric mapping of lakes was predominantly conducted with the use of highly-priced methods such as airborne lidars, active imaging sonars, multibeam echosounders. With the advancements in GIS and emergence of remotely sensed data new approaches for bathymetry extraction were developed. However, despite a high motivation to obtain bathymetric information for small lakes from remotely sensed data, there is a lack of reliable methods that can be implemented under various climate conditions and on a wide scale. In this paper several remote-sensing-based methods for bathymetry mapping of small lakes are discussed. The new Ice, Cloud, and land Elevation Satellite-2 (ICESat-2) data was used to extract bathymetric information on three small lakes of Kazakhstan. The assessment of ICESat-2 for lake bathymetry extraction was conducted using field measurements as the validation data.
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Zhu, Siyu, Baojian Liu, Wei Wan, et al. "A New Digital Lake Bathymetry Model Using the Step-Wise Water Recession Method to Generate 3D Lake Bathymetric Maps Based on DEMs." Water 11, no. 6 (2019): 1151. http://dx.doi.org/10.3390/w11061151.
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The availability of lake bathymetry maps is imperative for estimating lake water volumes and their variability, which is a sensitive indicator of climate. It is difficult, if not impossible, to obtain bathymetric measurements from all of the thousands of lakes across the globe due to costly labor and/or harsh topographic regions. In this study, we develop a new digital lake bathymetry model (DLBM) using the step-wise water recession method (WRM) to generate 3-dimensional lake bathymetric maps based on the digital elevation model (DEM) alone, with two assumptions: (1) typically, the lake’s bathymetry is formed and shaped by geological processes similar to those that shaped the surrounding landmasses, and (2) the agent rate of water (the thickness of the sedimentary deposit proportional to the lake water depth) is uniform. Lake Ontario and Lake Namco are used as examples to demonstrate the development, calibration, and refinement of the model. Compared to some other methods, the estimated 3D bathymetric maps using the proposed DLBM could overcome the discontinuity problem to adopt the complex topography of lake boundaries. This study provides a mathematically robust yet cost-effective approach for estimating lake volumes and their changes in regions lacking field measurements of bathymetry, for example, the remote Tibetan Plateau, which contains thousands of lakes.
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Bures, Ludek, Petra Sychova, Petr Maca, Radek Roub, and Stepan Marval. "River Bathymetry Model Based on Floodplain Topography." Water 11, no. 6 (2019): 1287. http://dx.doi.org/10.3390/w11061287.
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An appropriate digital elevation model (DEM) is required for purposes of hydrodynamic modelling of floods. Such a DEM describes a river’s bathymetry (bed topography) as well as its surrounding area. Extensive measurements for creating accurate bathymetry are time-consuming and expensive. Mathematical modelling can provide an alternative way for representing river bathymetry. This study explores new possibilities in mathematical depiction of river bathymetry. A new bathymetric model (Bathy-supp) is proposed, and the model’s ability to represent actual bathymetry is assessed. Three statistical methods for the determination of model parameters were evaluated. The best results were achieved by the random forest (RF) method. A two-dimensional (2D) hydrodynamic model was used to evaluate the influence of the Bathy-supp model on the hydrodynamic modelling results. Also presented is a comparison of the proposed model with another state-of-the-art bathymetric model. The study was carried out on a reach of the Otava River in the Czech Republic. The results show that the proposed model’s ability to represent river bathymetry exceeds that of his current competitor. Use of the bathymetric model may have a significant impact on improving the hydrodynamic model results.
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Palaseanu-Lovejoy, Monica, Oleg Alexandrov, Jeff Danielson, and Curt Storlazzi. "SaTSeaD: Satellite Triangulated Sea Depth Open-Source Bathymetry Module for NASA Ames Stereo Pipeline." Remote Sensing 15, no. 16 (2023): 3950. http://dx.doi.org/10.3390/rs15163950.
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We developed the first-ever bathymetric module for the NASA Ames Stereo Pipeline (ASP) open-source topographic software called Satellite Triangulated Sea Depth, or SaTSeaD, to derive nearshore bathymetry from stereo imagery. Correct bathymetry measurements depend on water surface elevation, and whereas previous methods considered the water surface horizontal, our bathymetric module accounts for the curvature of the Earth in the imagery. The process is semiautomatic, reliable, and repeatable, independent of any external bathymetry data eliminating user bias in selecting bathymetry calibration points, and it can generate a fully integrated and seamless topo-bathymetry digital elevation model (TBDEM) in the same coordinate system, comparable with the band-ratio method irrespective of the regression method used for the band-ratio algorithm. The ASP output can be improved by applying a camera bundle adjustment to minimize reprojection errors and by alignment to a more accurate topographic (above water) surface without any bathymetric input since the derived TBDEM is a rigid surface. These procedures can decrease bathymetry root mean square errors from 30 to 80 percent, depending on environmental conditions, the quality of satellite imagery, and the spectral band used (e.g., blue, green, or panchromatic).
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Yang, Jian, Yue Ma, Huiying Zheng, Yuanfei Gu, Hui Zhou, and Song Li. "Analysis and Correction of Water Forward-Scattering-Induced Bathymetric Bias for Spaceborne Photon-Counting Lidar." Remote Sensing 15, no. 4 (2023): 931. http://dx.doi.org/10.3390/rs15040931.
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The new spaceborne photon-counting lidar, i.e., ICESat-2, has shown great advantages in obtaining nearshore bathymetry at a global scale. The forward-scattering effect in the water column is one of the main error sources in airborne lidar bathymetry (ALB). However, the magnitude of the bathymetric bias for spaceborne lidars and how can we effectively correct this bias have not been evaluated and are very worthy of investigation. In this study, the forward-scattering effect on spaceborne photon-counting lidar bathymetry is quantitatively modeled and analyzed based on the semi-analytic Monte Carlo simulation method. Meanwhile, an empirical formula for correcting forward-scattering-induced bathymetric bias specific to ICESat-2 is derived. When the water depth exceeds 20 m, this bias cannot be neglected for ICESat-2 even in clear open ocean waters. In two study areas with local in situ measurements (St. Thomas and Hawaii), the bathymetric bias of ICESat-2 in deep waters (>20 m) is corrected from exceeding 50 cm to less than 13 cm using the proposed empirical formula. This study is valuable to evaluate and correct the forward-scattering-induced bias for the existing ICESat-2 and is also fundamental to optimizing the hardware parameters of a possible future photon-counting bathymetric lidar.
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Specht, Cezary, Emilian Świtalski, and Mariusz Specht. "Application of an Autonomous/Unmanned Survey Vessel (ASV/USV) in Bathymetric Measurements." Polish Maritime Research 24, no. 3 (2017): 36–44. http://dx.doi.org/10.1515/pomr-2017-0088.
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AbstractThe accuracy of bathymetric maps, especially in the coastal zone, is very important from the point of view of safety of navigation and transport. Due to the continuous change in shape of the seabed, these maps are fast becoming outdated for precise navigation. Therefore, it is necessary to perform periodical bathymetric measurements to keep them updated on a current basis. At present, none of the institutions in Poland (maritime offices, Hydrographic Office of the Polish Navy) which are responsible for implementation of this type of measurements has at their disposal a hydrographic vessel capable of carrying out measurements for shallow waters (at depths below 1 m). This results in emergence of large areas for which no measurement data have been obtained and, consequently, the maps in the coastal zones are rather unreliable.The article presents the concept of bathymetric measurements for shallow waters with the use of an autonomous, unmanned survey vessel (ASV/USV). For this purpose, the authors modernized a typical ASV/USV unit with standard radio remote control system to the fully autonomous mode. As part of the modernization, the route planning software was created. The developed software works based on, alternatively, GNSS measurements of the coastline, or satellite images. The system was supplemented by an own autopilot (adapted for flying drones). Moreover, the method of controlling electric motors was changed thanks to the use of own electronic circuit.The modernized ASV/USV measuring system was verified by performing bathymetric measurements of the retention reservoir in Gdansk, Poland. Then, the obtained measurement data were used to create a digital bottom model and a bathymetric map of the reservoir.
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Zhong, Jing, Jie Sun, Zulong Lai, and Yan Song. "Nearshore Bathymetry from ICESat-2 LiDAR and Sentinel-2 Imagery Datasets Using Deep Learning Approach." Remote Sensing 14, no. 17 (2022): 4229. http://dx.doi.org/10.3390/rs14174229.
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Accurate bathymetric data is crucial for marine and coastal ecosystems. A lot of studies have been carried out for nearshore bathymetry using satellite data. The approach adopted extensively in shallow water depths estimation has recently been one of empirical models. However, the linear empirical model is simple and only takes limited band information at each bathymetric point into consideration. It may be not suitable for complex environments. In this paper, a deep learning framework was proposed for nearshore bathymetry (DL-NB) from ICESat-2 LiDAR and Sentinel-2 Imagery datasets. The bathymetric points from the spaceborne ICESat-2 LiDAR were extracted instead of in situ measurements. By virtue of the two-dimensional convolutional neural network (2D CNN), DL-NB can make full use of the initial multi-spectral information of Sentinel-2 at each bathymetric point and its adjacent areas during the training. Based on the trained model, the bathymetric maps of several study areas were produced including the Appalachian Bay (AB), Virgin Islands (VI), and Cat Island (CI) of the United States. The performance of DL-NB was evaluated by empirical method, machine learning method and multilayer perceptron (MLP). The results indicate that the accuracy of the DL-NB is better than comparative methods can in nearshore bathymetry. After quantitative analysis, the RMSE of DL-NB could achieve 1.01 m, 1.80 m and 0.28 m in AB, VI and CI respectively. Given the same data conditions, the proposed method can be applied for high precise global scale and multitemporal nearshore bathymetric maps generation, which are beneficial to marine environmental change assessment and conservation.
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Specht, Mariusz. "Methodology for Performing Bathymetric and Photogrammetric Measurements Using UAV and USV Vehicles in the Coastal Zone." Remote Sensing 16, no. 17 (2024): 3328. http://dx.doi.org/10.3390/rs16173328.
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The coastal zone is constantly exposed to marine erosion, rising water levels, waves, tides, sea currents, and debris transport. As a result, there are dynamic changes in the coastal zone topography, which may have negative effects on the aquatic environment and humans. Therefore, in order to monitor the changes in landform taking place in the coastal zone, periodic bathymetric and photogrammetric measurements should be carried out in an appropriate manner. The aim of this review is to develop a methodology for performing bathymetric and photogrammetric measurements using an Unmanned Aerial Vehicle (UAV) and an Unmanned Surface Vehicle (USV) in a coastal zone. This publication shows how topographic and bathymetric monitoring should be carried out in this type of zone in order to obtain high-quality data that will be used to develop a Digital Terrain Model (DTM). The methodology for performing photogrammetric surveys with the use of a drone in the coastal zone should consist of four stages: the selection of a UAV, the development of a photogrammetric flight plan, the determination of the georeferencing method for aerial photos, and the specification as to whether there are meteorological conditions in the studied area that enable the implementation of an aerial mission through the use of a UAV. Alternatively, the methodology for performing bathymetric measurements using a USV in the coastal zone should consist of three stages: the selection of a USV, the development of a hydrographic survey plan, and the determination of the measurement conditions in the studied area and whether they enable measurements to be carried out with the use of a USV. As can be seen, the methodology for performing bathymetric and photogrammetric measurements using UAV and USV vehicles in the coastal zone is a complex process and depends on many interacting factors. The correct conduct of the research will affect the accuracy of the obtained measurement results, the basis of which a DTM of the coastal zone is developed. Due to dynamic changes in the coastal zone topography, it is recommended that bathymetric measurements and photogrammetric measurements with the use of UAV and USV vehicles should be carried out simultaneously on the same day, before or after the vegetation period, to enable the accurate measurement of the shallow waterbody depth.
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Tang, K. K. W., M. R. Mahmud, A. Hussaini, and A. G. Abubakar. "EVALUATING IMAGERY-DERIVED BATHYMETRY OF SEABED TOPOGRAPHY TO SUPPORT MARINE CADASTRE." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-4/W16 (October 1, 2019): 633–39. http://dx.doi.org/10.5194/isprs-archives-xlii-4-w16-633-2019.
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Abstract. The Department of Survey and Mapping Malaysia has introduced marine cadastre system to register the rights, other valid interests therein and ownership of spatially determined parcels in the context of the marine environment yet the implementation of the system is still at the rudimentary stage. One of the big issues here is gathering land-to-seabed data to create a seamless topographic base map to support its marine cadastre project. Seabed bathymetric mapping in coastal zone is one of the major components to support marine cadastre. In the past, accurate bathymetric measurements can be a very laborious task in hydrographic surveying. Traditional vessel-based acoustic soundings require a lot of time, operation cost and others. Today, human’s ingenuity to yield bathymetric depths from multispectral images as an alternative source to chart the seabed topography has brought in new revolution to hydrography. The paper is initiated for evaluating water depth determination by using imagery-derived bathymetry technique and check its correlation with in-situ bathymetry depths. In the course of experiment, it demonstrates a good correlation between the imagery-derived bathymetric depths and the in-situ bathymetric depths, and majority of the derived depths have passed the minimum requirement of the IHO S-44 survey standard. The result also shows that these empirical models deliver promising outcome which can be use over the turbid environment setting. Hence, imagery-derived bathymetry approach can be an efficient and repeatable way to derive the seabed topography over a huge segment of coastal region. This study also suggests that imagery-derived bathymetry approach can be recognised as an aid in seabed topographic mapping to support marine cadastre initiative.
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Geheran, Matthew P., Katherine R. DeVore, Matthew W. Farthing, et al. "Estimating Nearshore Morphological Change through Ensemble Optimal Interpolation with Altimetric Data." Journal of Marine Science and Engineering 12, no. 7 (2024): 1168. http://dx.doi.org/10.3390/jmse12071168.
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Nearshore bathymetry changes on scales of hours to months in ways that strongly impact coastal processes. However, even at the best-monitored sites, surveys are typically not conducted with sufficient frequency to capture important changes such as sandbar migration. As a result, nearshore models often rely on outdated bathymetric boundary conditions, which may introduce significant errors. In this study, we investigate ensemble optimal interpolation (EnOI) as a method to update survey-derived bathymetry with altimetric measurements that are spatially sparse but have high temporal availability. We present the results of two synthetic examples and two field data experiments that demonstrate the ability of the method to accurately track morphological change between surveys. The method reduces the RMSE relative to a static bathymetry (corresponding to the day before the first assimilation step) by 23% to 68%. When compared with an estimate linearly interpolated between survey-derived bathymetries, the EnOI analysis reduces the RMSE by 19% to 47% in three out of the four experiments.
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He, Chunlong, Qigang Jiang, and Peng Wang. "An Improved Physics-Based Dual-Band Model for Satellite-Derived Bathymetry Using SuperDove Imagery." Remote Sensing 16, no. 20 (2024): 3801. http://dx.doi.org/10.3390/rs16203801.
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Shallow water bathymetry is critical for environmental monitoring and maritime security. Current widely used statistical models based on passive optical satellite remote sensing often rely on prior bathymetric data, limiting their application to regions lacking such information. In contrast, the physics-based dual-band log-linear analytical model (P-DLA) can estimate shallow water bathymetry without in situ measurements, offering significant potential. However, the quasi-analytical algorithm (QAA) used in the P-DLA is sensitive to non-ideal pixels, resulting in unstable bathymetry estimation. To address this issue and evaluate the potential of SuperDove imagery for bathymetry estimation in regions without prior bathymetric data, this study proposes an improved physics-based dual-band model (IPDB). The IPDB replaces the QAA with a spectral optimization algorithm that integrates deep and shallow water sample pixels to estimate diffuse attenuation coefficients for the blue and green bands. This allows for more accurate estimation of shallow water bathymetry. The IPDB was tested on SuperDove images of Dongdao Island, Yongxing Island, and Yongle Atoll. The results showed that SuperDove images are capable of estimating shallow water bathymetry in regions without prior bathymetric data. The IPDB achieved Root Mean Square Error (RMSE) values below 1.7 m and R2 values above 0.89 in all three study areas, indicating strong performance in bathymetric estimation. Notably, the IPDB outperformed the standard P-DLA model in accuracy. Furthermore, this study outlines four sampling principles that, when followed, ensure that variations in the spatial distribution of sampling pixels do not significantly impact model performance. This study also showed that the blue–green band combination is optimal for the analytical expression of the physics-based dual-band model.
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Tang, Kelvin Kang Wee, and Mohd Razali Mahmud. "The Accuracy of Satellite Derived Bathymetry in Coastal and Shallow Water Zone." International Journal of Built Environment and Sustainability 8, no. 3 (2021): 1–8. http://dx.doi.org/10.11113/ijbes.v8.n3.681.
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Precise and accurate bathymetric measurements are conventionally acquired by means of ship-based acoustic equipment. Nevertheless, recent multispectral satellite imagery has been utilised as a substitute source to map the seabed topography which indicates new revolution in hydrographic surveying. This study assesses the satellite bathymetric depth’s accuracy based on the vertical uncertainty as stated in the Standards for Hydrographic Surveys issued by the International Hydrographic Organization. Two empirical algorithms, namely, Dierssen’s and Stumpf’s approaches have been adopted to model the seafloor topography over the coastal and shallow water at Tanjung Kupang, Malaysia. The outcomes demonstrate a decent correlation between the derived water depths and the sounding values acquired from a ship-based acoustic survey. For instance, a total of 1,215 out of the 1,367 generated water depths by Stumpf’s model have hit the minimum standard of survey in S-44. Similarly, out of the 1,367 samples from Diessen’s model, 1,211 samples have met the minimum requirement listed in the survey standard. The results demonstrate both imageries derived bathymetry models convey promising results which can be ultilised for bathymetric mapping application. Therefore, this imagery derived bathymetry can be considered as an alternative bathymetric surveying technique to supply cost-effective solution and survey data to support the Blue Economy and Sustainable Development Goals 14.
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Li, Jiwei, David E. Knapp, Mitchell Lyons, et al. "Automated Global Shallow Water Bathymetry Mapping Using Google Earth Engine." Remote Sensing 13, no. 8 (2021): 1469. http://dx.doi.org/10.3390/rs13081469.
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Global shallow water bathymetry maps offer critical information to inform activities such as scientific research, environment protection, and marine transportation. Methods that employ satellite-based bathymetric modeling provide an alternative to conventional shipborne measurements, offering high spatial resolution combined with extensive coverage. We developed an automated bathymetry mapping approach based on the Sentinel-2 surface reflectance dataset in Google Earth Engine. We created a new method for generating a clean-water mosaic and a tailored automatic bathymetric estimation algorithm. We then evaluated the performance of the models at six globally diverse sites (Heron Island, Australia; West Coast of Hawaiʻi Island, Hawaiʻi; Saona Island, Dominican Republic; Punta Cana, Dominican Republic; St. Croix, United States Virgin Islands; and The Grenadines) using 113,520 field bathymetry sampling points. Our approach derived accurate bathymetry maps in shallow waters, with Root Mean Square Error (RMSE) values ranging from 1.2 to 1.9 m. This automatic, efficient, and robust method was applied to map shallow water bathymetry at the global scale, especially in areas which have high biodiversity (i.e., coral reefs).
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Parrish, Christopher E., Lori A. Magruder, Amy L. Neuenschwander, Nicholas Forfinski-Sarkozi, Michael Alonzo, and Michael Jasinski. "Validation of ICESat-2 ATLAS Bathymetry and Analysis of ATLAS’s Bathymetric Mapping Performance." Remote Sensing 11, no. 14 (2019): 1634. http://dx.doi.org/10.3390/rs11141634.
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NASA’s Ice, Cloud, and Land Elevation Satellite-2 (ICESat-2) was launched in September, 2018. The satellite carries a single instrument, ATLAS (Advanced Topographic Laser Altimeter System), a green wavelength, photon-counting lidar, enabling global measurement and monitoring of elevation with a primary focus on the cryosphere. Although bathymetric mapping was not one of the design goals for ATLAS, pre-launch work by our research team showed the potential to map bathymetry with ICESat-2, using data from MABEL (Multiple Altimeter Beam Experimental Lidar), NASA’s high-altitude airborne ATLAS emulator, and adapting the laser-radar equation for ATLAS specific parameters. However, many of the sensor variables were only approximations, which limited a full assessment of the bathymetric mapping capabilities of ICESat-2 during pre-launch studies. Following the successful launch, preliminary analyses of the geolocated photon returns have been conducted for a number of coastal sites, revealing several salient examples of seafloor detection in water depths of up to ~40 m. The geolocated seafloor photon returns cannot be taken as bathymetric measurements, however, since the algorithm used to generate them is not designed to account for the refraction that occurs at the air–water interface or the corresponding change in the speed of light in the water column. This paper presents the first early on-orbit validation of ICESat-2 bathymetry and quantification of the bathymetric mapping performance of ATLAS using data acquired over St. Thomas, U.S. Virgin Islands. A refraction correction, developed and tested in this work, is applied, after which the ICESat-2 bathymetry is compared against high-accuracy airborne topo-bathymetric lidar reference data collected by the U.S. Geological Survey (USGS) and the National Oceanic and Atmospheric Administration (NOAA). The results show agreement to within 0.43—0.60 m root mean square error (RMSE) over 1 m grid resolution for these early on-orbit data. Refraction-corrected bottom return photons are then inspected for four coastal locations around the globe in relation to Visible Infrared Imaging Radiometer Suite (VIIRS) Kd(490) data to empirically determine the maximum depth mapping capability of ATLAS as a function of water clarity. It is demonstrated that ATLAS has a maximum depth mapping capability of nearly 1 Secchi in depth for water depths up to 38 m and Kd(490) in the range of 0.05–0.12 m−1. Collectively, these results indicate the great potential for bathymetric mapping with ICESat-2, offering a promising new tool to assist in filling the global void in nearshore bathymetry.
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Choiński, Adam, and Agnieszka Strzelczak. "Bathymetric measurements of Morskie Oko Lake." Limnological Review 11, no. 2 (2011): 89–93. http://dx.doi.org/10.2478/v10194-011-0030-4.
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Bathymetric measurements of Morskie Oko LakeThe aim of this study was to gather and summarize bathymetric measurements of Morskie Oko Lake which have been carried out up to now. Apart from the two existing plans from 1909 and 1934, a plan presenting the arrangement of isobaths in 1879 was worked out on the basis of numerical data. Moreover, after field investigation with an echo sounder in 2011, a new bathymetric plan was created. All four plans were used to calculate the basic morphometric parameters of Morskie Oko. Bathygraphic curves were determined from the volume of water found by measuring the areas between consecutive isobaths. The least accurate data come from 1879 while there is a considerable resemblance between the plans dated to 1934 and 2011. In case of the most recent plan, the measurements were for the first time related to the average, multi-annual (1963-2010) water level. Thus, the greatest depth found in 2011 can be regarded as the maximum depth. Further bathymetric studies could help to determine the rate of shallowing of Morskie Oko lake caused by weathered rock material, transported for instance by avalanches.
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Kjeldsen, Kristian Kjellerup, Reimer Wilhelm Weinrebe, Jørgen Bendtsen, Anders Anker Bjørk, and Kurt Henrik Kjær. "Multibeam bathymetry and CTD measurements in two fjord systems in southeastern Greenland." Earth System Science Data 9, no. 2 (2017): 589–600. http://dx.doi.org/10.5194/essd-9-589-2017.
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Abstract. We present bathymetry and hydrological observations collected in the summer of 2014 from two fjord systems in southeastern Greenland with a multibeam sonar system. Our results provide a detailed bathymetric map of the fjord complex around the island of Skjoldungen in Skjoldungen Fjord and the outer part of Timmiarmiut Fjord and show far greater depths compared to the International Bathymetric Chart of the Arctic Ocean. The hydrography collected shows different properties in the fjords with the bottom water masses below 240 m in Timmiarmiut Fjord being 1–2 °C warmer than in the two fjords around Skjoldungen, but data also illustrate the influence of sills on the exchange of deeper water masses within fjords. Moreover, evidence of subglacial discharge in Timmiarmiut Fjord, which is consistent with satellite observations of ice mélange set into motion, adds to our increasing understanding of the distribution of subglacial meltwater. Data are available through the PANGAEA website at https://doi.pangaea.de/10.1594/PANGAEA.860627.
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Zhu, Weidong, Li Ye, Zhenge Qiu, et al. "Research of the Dual-Band Log-Linear Analysis Model Based on Physics for Bathymetry without In-Situ Depth Data in the South China Sea." Remote Sensing 13, no. 21 (2021): 4331. http://dx.doi.org/10.3390/rs13214331.
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The current widely used bathymetric inversion model based on multispectral satellite imagery mostly relies on in-situ depth data for establishing a liner/non-linear relationship between water depth and pixel reflectance. This paper evaluates the performance of a dual-band log-linear analysis model based on physics (P-DLA) for bathymetry without in-situ depth data. This is done using WorldView-2 images of blue and green bands. Further, the pixel sampling principles for solving the four key parameters of the model are summarized. Firstly, this paper elaborates on the physical mechanism of the P-DLA model. All unknown parameters of the P-DLA model are solved by different types of sampling pixels extracted from multispectral images for bathymetric measurements. Ganquan Island and Zhaoshu Island, where accuracy evaluation is performed for the bathymetric results of the P-DLA model with in-situ depth data, were selected to be processed using the method to evaluate its performance. The root mean square errors (RMSEs) of the Ganquan Island and Zhaoshu Island results are 1.69 m and 1.74 m with the mean relative error (MREs) of 14.8% and 18.3%, respectively. Meanwhile, the bathymetric inversion is performed with in-situ depth data using the traditional dual-band log-linear regression model (DLR). The results show that the accuracy of the P-DLA model bathymetry without in-situ depth data is roughly equal to that of the DLR model water depth inversion based on in-situ depth data. The results indicate that the P-DLA model can still obtain relatively ideal bathymetric results despite not having actual bathymetric data in the model training. It also demonstrates underwater microscopic features and changes in the islands and reefs.
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Li, Jie, Zhipeng Dong, Lubin Chen, Qiuhua Tang, Jiaoyu Hao, and Yujie Zhang. "Multi-Temporal Image Fusion-Based Shallow-Water Bathymetry Inversion Method Using Active and Passive Satellite Remote Sensing Data." Remote Sensing 17, no. 2 (2025): 265. https://doi.org/10.3390/rs17020265.
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In the active–passive fusion-based bathymetry inversion method using single-temporal images, image data often suffer from errors due to inadequate atmospheric correction and interference from neighboring land and water pixels. This results in the generation of noise, making high-quality data difficult to obtain. To address this problem, this paper introduces a multi-temporal image fusion method. First, a median filter is applied to separate land and water pixels, eliminating the influence of adjacent land and water pixels. Next, multiple images captured at different times are fused to remove noise caused by water surface fluctuations and surface vessels. Finally, ICESat-2 laser altimeter data are fused with multi-temporal Sentinel-2 satellite data to construct a machine learning framework for coastal bathymetry. The bathymetric control points are extracted from ICESat-2 ATL03 products rather than from field measurements. A backpropagation (BP) neural network model is then used to incorporate the initial multispectral information of Sentinel-2 data at each bathymetric point and its surrounding area during the training process. Bathymetric maps of the study areas are generated based on the trained model. In the three study areas selected in the South China Sea (SCS), the validation is performed by comparing with the measurement data obtained using shipborne single-beam or multi-beam and airborne laser bathymetry systems. The root mean square errors (RMSEs) of the model using the band information after image fusion and median filter processing are better than 1.82 m, and the mean absolute errors (MAEs) are better than 1.63 m. The results show that the proposed method achieves good performance and can be applied for shallow-water terrain inversion.
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Zhong, Junsheng, Xiuguo Liu, Xiang Shen, and Liming Jiang. "A Robust Algorithm for Photon Denoising and Bathymetric Estimation Based on ICESat-2 Data." Remote Sensing 15, no. 8 (2023): 2051. http://dx.doi.org/10.3390/rs15082051.
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The Ice, Cloud, and Land Elevation Satellite 2 (ICESat-2) is equipped with an Advanced Terrain Laser Altimeter System (ATLAS) with the capability of penetrating water bodies, making it a widely utilized tool for the bathymetry of various aquatic environments. However, the laser sensor often encounters a significant number of noise photons due to various factors such as sunlight, water quality, and after-pulse effect. These noise photons significantly compromise the accuracy of bathymetry measurements. In an effort to address this issue, this study proposes a two-step method for photon denoising by utilizing a method combining the DBSCAN algorithm and a two-dimensional window filter, achieving an F1 score of 0.94. A robust M-estimation method was employed to estimate the water depth of the denoised and refraction-corrected bathymetric photons, achieving an RMSE of 0.30 m. The method proposed in this paper preserves as much information as possible about signal photons, increases the number of bathymetric points, enhances the resistance to gross error, and guarantees the accuracy of bathymetry measurements while outlining the underwater topography. While the method is not fully automated and requires setting parameters, the fixed parameter values allow for efficient batch denoising of underwater photon points in different environments.
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Evagorou, Evagoras, Athanasios Argyriou, Nikos Papadopoulos, Christodoulos Mettas, George Alexandrakis, and Diofantos Hadjimitsis. "Evaluation of Satellite-Derived Bathymetry from High and Medium-Resolution Sensors Using Empirical Methods." Remote Sensing 14, no. 3 (2022): 772. http://dx.doi.org/10.3390/rs14030772.
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This study evaluates the accuracy of bathymetric maps generated from multispectral satellite datasets acquired from different multispectral sensors, namely the Worldview 2, PlanetScope, and the Sentinel 2, in the bay of Elounda in Crete. Image pre-processing steps were implemented before the use of the three empirical methods for estimating bathymetry. A dedicated correction and median filter have been applied to minimize noise from the sun glint and the sea waves. Due to the spectral complexity of the selected study area, statistical correlation with different numbers of bands was applied. The analysis indicated that blue and green bands obtained the best results with higher accuracy. Then, three empirical models, namely the Single Band Linear Algorithm, the Multiband Linear Algorithm, and the Ratio Transform Algorithm, were applied to the three multispectral images. Bathymetric and error distribution maps were created and used for the error assessment of results. The accuracy of the bathymetric maps estimated from different empirical models is compared with on-site Single beam Echo Sounder measurements. The most accurate bathymetric maps were obtained using the WorldView 2 and the empirical model of the Ratio Transform algorithm, with the RMSE reaching 1.01 m.
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Lingua, A. M., P. Maschio, A. Spadaro, P. Vezza, and G. Negro. "ITERATIVE REFRACTION-CORRECTION METHOD ON MVS-SFM FOR SHALLOW STREAM BATHYMETRY." International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLVIII-1/W1-2023 (May 25, 2023): 249–55. http://dx.doi.org/10.5194/isprs-archives-xlviii-1-w1-2023-249-2023.
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Abstract. Extracting accurate bathymetric information from clear, shallow waters in complex riverine environments can be challenging, but it is crucial for many applications, such as hydraulic modeling, ecological monitoring, and sediment transport analysis. Multi-view stereo photogrammetry (MVS-SfM) has emerged as a promising technique for acquiring high-resolution bathymetric data from aerial imagery. However, the accuracy of MVS-SfM can be affected by various factors, including water refraction, which can distort the depth measurements. In this study, iterative Dietrich’s refraction-correction method is tested for extracting bathymetry from MVS-SfM in a complex riverine environment. Moreover, we proposed a workflow for applying the method using raster data files, which can be more readily available than point clouds. It also compared the obtained results with previous applications and evaluated them using statistical indices and ratios. For this case study, the multicamera refraction method produces bathymetric datasets with accuracies of ~0.019% of the flying height and precisions of ~0.07% of the flying height. This study contributes to increased confidence in exploiting aerial imagery for bathymetric mapping in photogrammetric procedures under field conditions and can facilitate the management and conservation of clear water systems.
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Drakopoulou, Paraskevi, Ioannis P. Panagiotopoulos, Marcello de Michele, et al. "Cross-Comparison of the “BathySent” Coastal Bathymetry to Sonar Measurements and Ratio Model Technique: Pilot Sites in the Aegean Sea (Greece)." Water 15, no. 18 (2023): 3168. http://dx.doi.org/10.3390/w15183168.
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The proposed novel “BathySent” approach for coastal bathymetric mapping, using the Copernicus Sentinel-2 mission, as well as the assessment and specification of the uncertainties of the derived depth results, are the objectives of this research effort. For this reason, Sentinel-2 bathymetry retrieval results for three different pilot sites in Greece (islands of Kos, Kasos, and Crete) were compared with ground-truth data. These data comprised high-resolution swath bathymetry measurements, single-beam echosounder measurements at very shallow waters (1–10 m), and the EMODnet DTM 2018 release. The synthetic tests showed that the “BathySent” approach could restitute bathymetry in the range of 5–14 m depth, showing a standard deviation of 2 m with respect to the sonar-based bathymetry. In addition, a comparison with the “ratio model” multispectral technique was performed. The absolute differences between conventional Earth Observation-based bathymetry retrieval approaches (i.e., linear ratio model) and the suggested innovative solution, using the Sentinel-2 data, were mainly lower than 2 m. According to the outcome evaluation, both models were considered to provide results that are more reliable within the depth zone of 5–25 m. The “ratio model” technique exhibits a saturation at ~25 m depth and demands ground calibration. Though, the “BathySent” method provides bathymetric data at a lower spatial resolution compared to the “ratio model” technique; however, it does not require in situ calibration and can also perform reliably deeper than 25 m.
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Wan, Ziying, Jiaying Li, and Lai Wei. "Optimized design of measurement wiring for multi-beam bathymetric system based on geometric modeling." Journal of Physics: Conference Series 2905, no. 1 (2024): 012032. https://doi.org/10.1088/1742-6596/2905/1/012032.
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Abstract In this paper, by establishing a mathematical model of the coverage width of the multi-beam bathymetric system and the overlap rate between adjacent strips, and combining it with a computer language program, several unknown quantities, such as the coverage width of the multi-beam bathymetric strips, the opening angle of the multi-beam transducer, and the overlap rate with the previous line of measurement, were accurately calculated. In addition, the study extended the model with optimization and in-depth analysis to determine the shortest measurement length of the multi-beam survey vessel. Finally, the validity and accuracy of the model in actual measurements are verified by testing the model. The model improves the working efficiency and measurement accuracy of the bathymetric system and provides an important theoretical basis for future marine scientific research.
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Specht, Mariusz, Marta Wiśniewska, Andrzej Stateczny, et al. "Analysis of Methods for Determining Shallow Waterbody Depths Based on Images Taken by Unmanned Aerial Vehicles." Sensors 22, no. 5 (2022): 1844. http://dx.doi.org/10.3390/s22051844.
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Hydrographic surveys enable the acquisition and processing of bathymetric data, which after being plotted onto nautical charts, can help to ensure safety of navigation, monitor changes in the coastal zone, and assess hydro-engineering structure conditions. This study involves the measurement of waterbody depth, identification of the seabed shape and geomorphology, the coastline course, and the location of underwater obstacles. Hydroacoustic systems mounted on vessels are commonly used in bathymetric measurements. However, there is also an increasing use of Unmanned Aerial Vehicles (UAV) that can employ sensors such as LiDAR (Light Detection And Ranging) or cameras previously not applied in hydrography. Current systems based on photogrammetric and remote sensing methods enable the determination of shallow waterbody depth with no human intervention and, thus, significantly reduce the duration of measurements, especially when surveying large waterbodies. The aim of this publication is to present and compare methods for determining shallow waterbody depths based on an analysis of images taken by UAVs. The perspective demonstrates that photogrammetric techniques based on the SfM (Structure-from-Motion) and MVS (Multi-View Stereo) method allow high accuracies of depth measurements to be obtained. Errors due to the phenomenon of water-wave refraction remain the main limitation of these techniques. It was also proven that image processing based on the SfM-MVS method can be effectively combined with other measurement methods that enable the experimental determination of the parameters of signal propagation in water. The publication also points out that the Lyzenga, Satellite-Derived Bathymetry (SDB), and Stumpf methods allow satisfactory depth measurement results to be obtained. However, they require further testing, as do methods using the optical wave propagation properties.
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Gao, Jay. "Bathymetric mapping by means of remote sensing: methods, accuracy and limitations." Progress in Physical Geography: Earth and Environment 33, no. 1 (2009): 103–16. http://dx.doi.org/10.1177/0309133309105657.
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Bathymetry has been traditionally charted via shipboard echo sounding. Alhough able to generate accurate depth measurements at points or along transects, this method is constrained by its high operating cost, inefficiency, and inapplicability to shallow waters. By comparison, remote sensing methods offer more flexible, efficient and cost-effective means of mapping bathymetry over broad areas. Remote sensing of bathymetry falls into two broad categories: non-imaging and imaging methods. The non-imaging method (as typified by LiDAR) is able to produce accurate bathymetric information over clear waters at a depth up to 70 m. However, this method is limited by the coarse bathymetric sampling interval and high cost. The imaging method can be implemented either analytically or empirically, or by a combination of both. Analytical or semi-analytical implementation is based on the manner of light transmission in water. It requires inputs of a number of parameters related to the properties of the atmosphere, water column, and bottom material. Thus, it is rather complex and difficult to use. By comparison, empirical implementation is much simpler and requires the input of fewer parameters. Both implementations can produce fine-detailed bathymetric maps over extensive turbid coastal and inland lake waters quickly, even though concurrent depth samples are essential. The detectable depth is usually limited to 20 m. The accuracy of the retrieved bathymetry varies with water depth, with the accuracy substantially lower at a depth beyond 12 m. Other influential factors include water turbidity and bottom materials, as well as image properties.
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Alokhina, O. V., B. P. Rusyn, M. M. Korus, D. V. Ivchenko, and N. A. Pits. "Comparison of GIS-based solutions for the assessment of lakes water volume: a case study of biosphere reserve "Shatskyi"." Information extraction and processing 2024, no. 52 (2024): 32–45. http://dx.doi.org/10.15407/vidbir2024.52.032.
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Understanding the volume of water in a lake is essential for assessing the health of the eco-system. Geographic Information Systems offer valuable tools for evaluating water volume in lakes, employing such methods as remote sensing for surface data and bathymetric surveys for lakebed data. By integrating techniques like sonar-based bathymetric surveys, precise depth measurements can be obtained to accurately calculate water volume. Based on the survey results, depth maps of three lakes of different sizes, depths, and origins within the Biosphere Reserve were created. Key morphometric characteristics and the volume of water mass were calculated from these surveys. However, it is important to note that these investigations can be expensive and time-consuming, especially for large lakes. It may not be feasible for lakes in remote or inaccessible areas. Hollister JW's (2010) bathymetry modelling method was applied, as an alternative to ground-based bathymetry survey results, to calculate the water volume of the above-mentioned lakes. The method is based on the assumption that the depth of the reservoir is a function of distance from the shoreline. The advantage of the method is the limited amount of input data, namely the area and maximum depth of the reservoir. The modeling bathymetry method is not suitable for very deep lakes like Svitiaz Lake, with complicated lake basin shapes, as demonstrated by comparing the results with ground-based bathymetric survey data. The lake with the smallest depth and more regular lake basin form, which is closer to a circular shape, such as Liutzimer Lake, provided the best results. Using the bathymetric modelling approach for other medium and small Bioreserve lakes could help to define the characteristics of water bodies for which this method can be extremely useful.
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Saylam, Kutalmis, Alejandra Briseno, Aaron R. Averett, and John R. Andrews. "Analysis of Depths Derived by Airborne Lidar and Satellite Imaging to Support Bathymetric Mapping Efforts with Varying Environmental Conditions: Lower Laguna Madre, Gulf of Mexico." Remote Sensing 15, no. 24 (2023): 5754. http://dx.doi.org/10.3390/rs15245754.
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In 2017, Bureau of Economic Geology (BEG) researchers at the University of Texas at Austin (UT Austin) conducted an airborne lidar survey campaign, collecting topographic and bathymetric data over Lower Laguna Madre, which is a shallow hypersaline lagoon in south Texas. Researchers acquired 60 hours of lidar data, covering an area of 1600 km2 with varying environmental conditions influencing water quality and surface heights. In the southernmost parts of the lagoon, in-situ measurements were collected from a boat to quantify turbidity, water transparency, and depths. Data analysis included processing of Sentinel-2 L1C satellite imagery pixel reflectance to classify locations with intermittent turbidity. Lidar measurements were compared to sonar recordings, and results revealed height differences of 5–25 cm where the lagoon was shallower than 3.35 m. Further, researchers analyzed satellite bathymetry at relatively transparent lagoon locations, and the results produced height agreement within 13 cm. The study concluded that bathymetric efforts with airborne lidar and optical satellite imaging have practical limitations and comparable results in large and dynamic shallow coastal estuaries, where in-situ measurements and tide adjustments are essential for height comparisons.
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Szatten, Dawid, Michał Habel, Luisa Pellegrini, and Michael Maerker. "Assessment of Siltation Processes of the Koronowski Reservoir in the Northern Polish Lowland Based on Bathymetry and Empirical Formulas." Water 10, no. 11 (2018): 1681. http://dx.doi.org/10.3390/w10111681.
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Artificial reservoirs have an important role in water management of river systems in terms of flood control, water supply and sediment budgeting. Therefore, it is important to maximize the time of their effective functioning. Sediment budgeting mainly depends on sediment transport dynamics. This article illustrates the impact of the Koronowski Reservoir on suspended sediments transported by the Brda River. The river system and the reservoir represent a typical lowland river environment. Our research is based on hydrological and sedimentological investigations on the reservoir and the river system. Field measurements were used to create the respective hydrological and sediment budgets. Moreover, we carried out bathymetric measurements to generate present day bathymetry and to calculate the reservoir’s capacity. We assessed the silting of the reservoir following the approaches proposed by Goncarov and Stonawski. We show that the size and dynamics of suspended sediments are mainly determined by the hydrological conditions. Moreover, we illustrate that the suspended sediment measurements made with the filtration method correlate with the nephelometric results. Generally, we show that the Koronowski Reservoir is mainly filled up by suspended sediments. We further illustrate that the level of siltation estimated with the empirical formulas deviates significantly from calculations made by bathymetric measurements.
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Zhang, Ziye. "Optimization of Multibeam Survey Measurement Based on Greedy Algorithm." Highlights in Science, Engineering and Technology 100 (May 22, 2024): 95–101. http://dx.doi.org/10.54097/y5gvg089.
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The effectiveness of multibeam bathymetric technology is widely recognized in marine depth measurements, especially in areas with complex and variable seafloor topography. This study aims to design a multibeam bathymetric survey plan for a specific maritime region, with the objectives of minimizing the total survey line length, ensuring comprehensive coverage of the target area, controlling the overlap between adjacent survey lines, and fully considering variations in seafloor topography. An optimization model was developed to determine the optimal route for comprehensive seafloor depth measurements within the specified maritime area.The model initially considers the influence of seafloor slope, establishing a single optimization objective model with the goal of minimizing the total survey line length. The decision variables primarily include the spacing between adjacent survey lines. The objective function of the model aims to reduce the number of survey lines, thereby achieving the minimization of the total survey line length. Constraints of the model encompass limitations on coverage range, calculations of coverage width, and relationships between survey lines. The model is solved using a greedy algorithm-based optimization approach, iteratively updating the positions of survey lines while determining the spacing based on the relationship between depth and coverage width. Ultimately, a layout of survey lines with the shortest total length, totaling 64 nautical miles with a configuration of 32 survey lines, is obtained for the assumed maritime area. Multibeam bathymetric technology holds broad prospects in the field of marine measurements, particularly in areas characterized by complex and variable seafloor topography. This study, by designing a multibeam bathymetric survey plan for a specific maritime region, not only contributes to improving measurement efficiency and accuracy but also reduces measurement costs and resource consumption. The outcomes of this research have significant practical implications for marine resource development, seafloor engineering construction, environmental protection, providing professionals in related fields with an effective measurement method and optimization strategy.
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Darmanin, Gareth, Adam Gauci, Alan Deidun, Luciano Galone, and Sebastiano D’Amico. "Satellite-Derived Bathymetry for Selected Shallow Maltese Coastal Zones." Applied Sciences 13, no. 9 (2023): 5238. http://dx.doi.org/10.3390/app13095238.
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Bathymetric information has become essential to help maintain and operate coastal zones. Traditional in situ bathymetry mapping using echo sounders is inefficient in shallow waters and operates at a high logistical cost. On the other hand, lidar mapping provides an efficient means of mapping coastal areas. However, this comes at a high acquisition cost as well. In comparison, satellite-derived bathymetry (SDB) provides a more cost-effective way of mapping coastal regions, albeit at a lower resolution. This work utilises all three of these methods collectively, to obtain accurate bathymetric depth data of two pocket beaches, Golden Bay and Għajn Tuffieħa, located in the northwestern region of Malta. Using the Google Earth Engine platform, together with Sentinel-2 data and collected in situ measurements, an empirical pre-processing workflow for estimating SDB was developed. Four different machine learning algorithms which produced differing depth accuracies by calibrating SDBs with those derived from alternative techniques were tested. Thus, this study provides an insight into the depth accuracy that can be achieved for shallow coastal regions using SDB techniques.
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Chang, Shuai, Dalong Zhang, Linfeng Zhang, et al. "A Joint Graph-Based Approach for Simultaneous Underwater Localization and Mapping for AUV Navigation Fusing Bathymetric and Magnetic-Beacon-Observation Data." Journal of Marine Science and Engineering 12, no. 6 (2024): 954. http://dx.doi.org/10.3390/jmse12060954.
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Accurate positioning is the necessary basis for autonomous underwater vehicles (AUV) to perform safe navigation in underwater tasks, such as port environment monitoring, target search, and seabed exploration. The position estimates of underwater navigation systems usually suffer from an error accumulation problem, which makes the AUVs difficult use to perform long-term and accurate underwater tasks. Underwater simultaneous localization and mapping (SLAM) approaches based on multibeam-bathymetric data have attracted much attention for being able to obtain error-bounded position estimates. Two problems limit the use of multibeam bathymetric SLAM in many scenarios. The first is that the loop closures only occur in the AUV path intersection areas. The second is that the data association is prone to failure in areas with gentle topographic changes. To overcome these problems, a joint graph-based underwater SLAM approach that fuses bathymetric and magnetic-beacon measurements is proposed in this paper. In the front-end, a robust dual-stage bathymetric data-association method is used to first detect loop closures on the multibeam bathymetric data. Then, a magnetic-beacon-detection method using Euler-deconvolution and optimization algorithms is designed to localize the magnetic beacons using a magnetic measurement sequence on the path. The loop closures obtained from both bathymetric and magnetic-beacon observations are fused to build a joint-factor graph. In the back-end, a diagnosis method is introduced to identify the potential false factors in the graph, thus improving the robustness of the joint SLAM system to outliers in the measurement data. Experiments based on field bathymetric datasets are performed to test the performance of the proposed approach. Compared with classic bathymetric SLAM algorithms, the proposed algorithm can improve the data-association accuracy by 50%, and the average positioning error after optimization converges to less than 10 m.
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Specht, Mariusz, Andrzej Stateczny, Cezary Specht, Szymon Widźgowski, Oktawia Lewicka, and Marta Wiśniewska. "Concept of an Innovative Autonomous Unmanned System for Bathymetric Monitoring of Shallow Waterbodies (INNOBAT System)." Energies 14, no. 17 (2021): 5370. http://dx.doi.org/10.3390/en14175370.
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Bathymetry is a subset of hydrography, aimed at measuring the depth of waterbodies and waterways. Measurements are taken inter alia to detect natural obstacles or other navigational obstacles that endanger the safety of navigation, to examine the navigability conditions, anchorages, waterways and other commercial waterbodies, and to determine the parameters of the safe depth of waterbodies in the vicinity of ports, etc. Therefore, it is necessary to produce precise and reliable seabed maps, so that any hazards that may occur, particularly in shallow waterbodies, can be prevented, including the high dynamics of hydromorphological changes. This publication is aimed at developing a concept of an innovative autonomous unmanned system for bathymetric monitoring of shallow waterbodies. A bathymetric and topographic system will use autonomous unmanned aerial and surface vehicles to study the seabed relief in the littoral zone (even at depths of less than 1 m), in line with the requirements set out for the most stringent International Hydrographic Organization (IHO) order—exclusive. Unlike other existing solutions, the INNOBAT system will enable the coverage of the entire surveyed area with measurements, which will allow a comprehensive assessment of the hydrographic and navigation situation in the waterbody to be conducted.
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Ji, Xue, Yi Ma, Jingyu Zhang, Wenxue Xu, and Yanhong Wang. "A Sub-Bottom Type Adaption-Based Empirical Approach for Coastal Bathymetry Mapping Using Multispectral Satellite Imagery." Remote Sensing 15, no. 14 (2023): 3570. http://dx.doi.org/10.3390/rs15143570.
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Accurate bathymetric data in shallow water is of increasing importance for navigation safety, coastal management, and marine transportation. Satellite-derived bathymetry (SDB) is widely accepted as an effective alternative to conventional acoustic measurements in coastal areas, providing high spatial and temporal resolution combined with extensive repetitive coverage. Many previous empirical SDB approaches are unsuitable for precision bathymetry mapping in various scenarios, due to the assumption of homogeneous bottom over the whole region, as well as the neglect of various interfering factors (e.g., turbidity) causing radiation attenuation. Therefore, this study proposes a bottom-type adaption-based SDB approach (BA-SDB). Under the consideration of multiple factors including suspended particulates and phytoplankton, it uses a particle swarm optimization improved LightGBM algorithm (PSO-LightGBM) to derive depth of each pre-segmented bottom type. Based on multispectral images of high spatial resolution and in situ observations of airborne laser bathymetry and multi-beam echo sounder, the proposed approach is applied in shallow water around Yuanzhi Island, and achieves the highest accuracy with an RMSE value of 0.85 m compared to log-ratio, multi-band, and classical machine learning methods. The results of this study show that the introduction of water-environment parameters improves the performance of the machine learning model for bathymetric mapping.
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Saylam, Kutalmis, Aaron R. Averett, Lucie Costard, Brad D. Wolaver, and Sarah Robertson. "Multi-Sensor Approach to Improve Bathymetric Lidar Mapping of Semi-Arid Groundwater-Dependent Streams: Devils River, Texas." Remote Sensing 12, no. 15 (2020): 2491. http://dx.doi.org/10.3390/rs12152491.
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Remote sensing technology enables detecting, acquiring, and recording certain information about objects and locations from distances relative to their geographic locations. Airborne Lidar bathymetry (ALB) is an active, non-imaging, remote sensing technology for measuring the depths of shallow and relatively transparent water bodies using light beams from an airborne platform. In this study, we acquired Lidar datasets using near-infrared and visible (green) wavelength with the Leica Airborne Hydrography AB Chiroptera-I system over the Devils River basin of southwestern Texas. Devils River is a highly groundwater-dependent stream that flows 150 km from source springs to Lake Amistad on the lower Rio Grande. To improve spatially distributed stream bathymetry in aquatic habitats of species of state and federal conservation interest, we conducted supplementary water-depth observations using other remote sensing technologies integrated with the airborne Lidar datasets. Ground penetrating radar (GPR) mapped the river bottom where vegetation impeded other active sensors in attaining depth measurements. We confirmed the accuracy of bathymetric Lidar datasets with a differential global positioning system (GPS) and compared the findings to sonar and GPR measurements. The study revealed that seamless bathymetric and geomorphic mapping of karst environments in complex settings (e.g., aquatic vegetation, entrained air bubbles, riparian zone obstructions) require the integration of a variety of terrestrial and remotely operated survey methods. We apply this approach to Devils River of Texas. However, the methods are applicable to similar streams globally.
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Mohammadloo, Tannaz H., Matt Geen, Jitendra S. Sewada, Mirjam Snellen, and Dick G. Simons. "Assessing the Performance of the Phase Difference Bathymetric Sonar Depth Uncertainty Prediction Model." Remote Sensing 14, no. 9 (2022): 2011. http://dx.doi.org/10.3390/rs14092011.
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Realistic predictions of the contribution of the uncertainty sources affecting the quality of the bathymetric measurements prior to a survey is of importance. To this end, models predicting these contributions have been developed. The objective of the present paper is to assess the performance of the bathymetric uncertainty prediction model for Phase Difference Bathymetric Sonars (PDBS) which is an interferometric sonar. Two data sets were acquired with the Bathyswath-2 system with a frequency of 234 kHz at average water depths of around 26 m and 8 m with pulse lengths equal to 0.0555 ms and 0.1581 ms, respectively. The comparison between the bathymetric uncertainties derived from the measurements and those predicted using the current model indicates a relatively good agreement except for the across-track distances close to the nadir. The performance of the prediction model can be improved by modifying the term addressing the effect of footprint shift, i.e., spatial decorrelation, on the bottom due to fact that at a given time the footprints seen by different receiving arrays are slightly different.
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Nugroho, Arif, Roynardus Sijabat, Achmad Muzni Chasanudin, and Isa Adi Subagjo. "Multibeam Bathymetric Measurements for Shallow Seabed Features Mapping using Unmanned Surface Vehicle." Jurnal Geofisika 20, no. 2 (2022): 62. https://doi.org/10.36435/jgf.v20i2.546.
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Subsea pipelines are constructions of pipelines laid onto or embedded into the seabed used for the distribution of fluids such as gas or oil. Over time, changes in the morphological seabed around the pipeline area possibly caused by natural processes such as erosion, scouring, or other geological anomalies may potentially lead to pipeline failure due to the presence of pipe anomalies in the form of free-spanning pipes. In general, this phenomenon occurs in pipelines with a dynamic sedimentation environment caused by tidal changes or underwater currents. Pertamina Hulu Mahakam (PHM) performs regular pipeline inspection as part of the pipeline maintenance program. Visual methods via underwater camera and acoustic methodology such as bathymetry were used to obtain the seabed pattern as well as underwater objects. The Mahakam pipeline networks extend from very shallow waters within the river delta area offshore at a depth more than 100m. For very shallow environments where manned vessels have a limited access, bathymetric measurements were done using Multibeam Echosounder (MBES) installed on an Unmanned Surface Vehicle (USV), controlled and monitored via radio communication over a certain distance. In 2021, PHM, in collaboration with Elnusa, conducted a pipeline inspection survey on one of the pipes, with a diameter of 24 inches and a length of 109 meters.. The results of the bathymetric measurements using the USV demonstrated that no indication of the presence of free-spanning pipelines could be found in the underwater vicinity. The depth of the river varied from -1.2 meters to 2.7 meters (Chart Datum). The topographical conditions showed a sloping riverbed with a maximum slope of 12°-13° from the direction fo the floodplain area towards the center of the river/main channel. Seven (7) pockmarks were identified around the pipeline having a diameter of about 29 to 52 cm and a depth of about 6 to 20 cm. In addition, attention should be paid to the possible presence of gas seepage in the pockmarks area, interpreted from the image of reflected acoustic waves in the water column captured by the MBES equipment. Keywords: Pipelines, bathymetry, seabed, MBES, USV
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Specht, Mariusz, Cezary Specht, Mariusz Wąż, Krzysztof Naus, Artur Grządziel, and Dominik Iwen. "Methodology for Performing Territorial Sea Baseline Measurements in Selected Waterbodies of Poland." Applied Sciences 9, no. 15 (2019): 3053. http://dx.doi.org/10.3390/app9153053.
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Baselines are used to establish the maritime boundaries of a coastal state which include the territorial sea, contiguous zone, exclusive economic zone and continental shelf; thus, they are instrumental in implementing state maritime policy. For Poland, as well as in other coastal states, baseline determination can be considered from both a legal and measurement-related point of view. This paper discusses an effective and optimal method of performing bathymetric measurements to enable territorial sea baseline determination in selected waterbodies of Poland. It presents a method for planning a hydrographic survey using both manned and unmanned vessels and presents oceanographic parameters that should be determined before and during hydrographic measurements, as well as a method of choosing the measuring equipment used in bathymetric measurements in ultra-shallow waters. The results of our analyses showed that using an unmanned vessel, on which a multi-GNSS receiver and a miniature MBES or SBES can be installed, is currently the optimum and the most effective method for determining the territorial sea baseline.
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Diaz, Gerardo, Yoav Lehahn та Emmanuel Nantet. "Satellite-Derived Bathymetry in Support of Maritime Archaeological Research—VENμS Imagery of Caesarea Maritima, Israel, as a Case Study". Remote Sensing 16, № 7 (2024): 1218. http://dx.doi.org/10.3390/rs16071218.
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Deriving bathymetry by means of multispectral satellite imagery proves to be a replicable method, offering high-resolution coverage over large areas while keeping costs low. Maritime archaeologists often require bathymetric mapping at a high resolution and with a large spatial coverage. In this paper, we demonstrate the implementation of SDB in maritime archaeology using high-resolution (5 m/pixel) data from Vegetation and Environment monitoring on a New Micro-Satellite (VENμS) imagery. We focus on the area of the Roman harbour of Sebastos, located at Caesarea Maritima along the Israeli coast of the Eastern Mediterranean. For extracting SDB, we take an empirical approach, which is based on the integration of satellite imagery and sonar depth measurements, resulting in a blue-green band ratio algorithm that provides reliable results up to a water depth of 17 m. Comparison with in situ depth measurements yielded an RMSE of 0.688 m. The SDB mapping is complemented by satellite-based identification of above- and below-water rocks. The presented approach can readily be replicated in other regions using various types of multispectral satellite imagery, particularly when only coarse bathymetric sonar data are available, thus substantially contributing to our ability to perform maritime archaeological research.
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Scheick, Jessica, Ellyn Enderlin, Emily Miller, and Gordon Hamilton. "First-Order Estimates of Coastal Bathymetry in Ilulissat and Naajarsuit Fjords, Greenland, from Remotely Sensed Iceberg Observations." Remote Sensing 11, no. 8 (2019): 935. http://dx.doi.org/10.3390/rs11080935.
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Warm water masses circulating at depth off the coast of Greenland play an important role in controlling rates of mass loss from the Greenland Ice Sheet through feedbacks associated with the melting of marine glacier termini. The ability of these warm waters to reach glacier termini is strongly controlled by fjord bathymetry, which was unmapped for the majority of Greenland’s fjords until recently. In response to the need for bathymetric measurements in previously uncharted areas, we developed two companion methods to infer fjord bathymetry using icebergs as depth sounders. The main premise of our methods centers around the idea that deep-drafted icebergs will become stranded in shallow water such that estimates of iceberg surface elevation can be used to infer draft, and thus water depth, under the assumption of hydrostatic equilibrium. When and where available, surface elevations of icebergs stranded on bathymetric highs were extracted from digital elevation models (DEMs) and converted to estimates of iceberg draft. To expand the spatial coverage of our inferred water depths beyond the DEM footprints, we used the DEMs to construct characteristic depth–width ratios and then inferred depths from satellite imagery-derived iceberg widths. We tested and applied the methods in two fjord systems in western Greenland with partially constrained bathymetry, Ilulissat Isfjord and Naajarsuit Fjord, to demonstrate their utility for inferring bathymetry using remote sensing datasets. Our results show that while the uncertainties associated with the methods are high (up to ±93 m), they provide critical first-order constraints on fjord bathymetry.
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Specht, Mariusz, Cezary Specht, Henryk Lasota, and Piotr Cywiński. "Assessment of the Steering Precision of a Hydrographic Unmanned Surface Vessel (USV) along Sounding Profiles Using a Low-Cost Multi-Global Navigation Satellite System (GNSS) Receiver Supported Autopilot." Sensors 19, no. 18 (2019): 3939. http://dx.doi.org/10.3390/s19183939.
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The performance of bathymetric measurements by traditional methods (using manned vessels) in ultra-shallow waters, i.e., lakes, rivers, and sea beaches with a depth of less than 1 m, is often difficult or, in many cases, impossible due to problems related to safe vessel maneuvering. For this reason, the use of shallow draft hydrographic Unmanned Surface Vessels (USV) appears to provide a promising alternative method for performing such bathymetric measurements. This article describes the modernisation of a USV to switch from manual to automatic mode, and presents a preliminary study aimed at assessing the suitability of a popular autopilot commonly used in Unmanned Aerial Vehicles (UAV), and a low-cost multi-Global Navigation Satellite System (GNSS) receiver cooperating with it, for performing bathymetric measurements in automated mode, which involves independent movement along a specified route (hydrographic sounding profiles). The cross track error (XTE) variable, i.e., the distance determined between a USV’s position and the sounding profile, measured transversely to the course, was adopted as the measure of automatic control precision. Moreover, the XTE value was statistically assessed in the publication.
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Borowiak, Dariusz, Kamil Nowiński, and Katarzyna Grabowska. "A new bathymetric survey of the Suwałki Landscape Park lakes." Limnological Review 16, no. 4 (2016): 185–97. http://dx.doi.org/10.1515/limre-2016-0020.
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Abstract The results of the latest bathymetric survey of 21 lakes in the Suwałki Landscape Park (SLP) are presented here. Measurements of the underwater lake topography were carried out in the years 2012–2013 using the hydroacoustic method (sonar Lawrence 480M). In the case of four lakes (Błędne, Pogorzałek, Purwin, Wodziłki) this was the first time a bathymetric survey had been performed. Field material was used to prepare bathymetric maps, which were then used for calculating the basic size and shape parameters of the lake basins. The results of the studies are shown against the nearly 90 year history of bathymetric surveying of the SLP lakes. In the light of the current measurements, the total area of the SLP lakes is over 634 hm2 and its limnic ratio is 10%. Lake water resources in the park were estimated at 143 037.1 dam3. This value corresponds to a retention index of 2257 mm. In addition, studies have shown that the previous morphometric data are not very accurate. The relative differences in the lake surface areas ranged from –14.1 to 9.1%, and in the case of volume – from –32.2 to 35.3%. The greatest differences in the volume, expressed in absolute values, were found in the largest SLP lakes: Hańcza (1716.1 dam3), Szurpiły (1282.0 dam3), Jaczno (816.4 dam3), Perty (427.1 dam3), Jegłówek (391.2 dam3) and Kojle (286.2 dam3). The smallest disparities were observed with respect to the data obtained by the IRS (Inland Fisheries Institute in Olsztyn). The IMGW (Institute of Meteorology and Water Management) bathymetric measurements were affected by some significant errors, and morphometric parameters determined on their basis are only approximate.
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Wang, Qiang, Ziyin Wu, Zhaocai Wu, et al. "Enhanced Seafloor Topography Inversion Using an Attention Channel 1D Convolutional Network Based on Multiparameter Gravity Data: Case Study of the Mariana Trench." Journal of Marine Science and Engineering 13, no. 3 (2025): 507. https://doi.org/10.3390/jmse13030507.
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Seafloor topography data are fundamental for marine resource development, oceanographic research, and maritime rights protection. However, approximately 75% of the ocean remains unsurveyed for bathymetry. Sole reliance on shipborne measurements is insufficient for constructing a global bathymetric model within a short timeframe; consequently, satellite altimetry-based inversion techniques are essential for filling data gaps. Recent advancements have improved the variety and quality of satellite altimetry gravity data. To leverage the complementary advantages of multiparameter gravity data, we propose a 1D convolutional neural network based on a convolutional attention module, termed the Attention Channel 1D Convolutional Network (AC1D). Results of a case study of the Mariana Trench indicated that the AC1D grid predictions exhibited improved agreement with single-beam depth checkpoints, with standard deviation reductions of 6.32%, 20.79%, and 36.77% and root mean square error reductions of 7.11%, 22.82%, and 50.99% compared with those of parallel linked backpropagation, the gravity–geological method, and a convolutional neural network, respectively. The AC1D grid demonstrated enhanced stability in multibeam bathymetric validation metrics and exhibited better consistency with multibeam bathymetry data and the GEBCO2023 grid. Power spectral density analysis revealed that AC1D effectively captured rich topographic signals when predicting terrain features with wavelengths below 6.33 km.
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H. Mohammadloo, Tannaz, Mirjam Snellen, and Dick G. Simons. "Assessing the Performance of the Multi-Beam Echo-Sounder Bathymetric Uncertainty Prediction Model." Applied Sciences 10, no. 13 (2020): 4671. http://dx.doi.org/10.3390/app10134671.
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Realistic predictions of the contribution of the various sources affecting the quality of the bathymetric measurements prior to a survey are of importance to ensure sufficient accuracy of the soundings. To this end, models predicting these contributions have been developed. The objective of the present paper is to assess the performance of the bathymetric uncertainty prediction model for modern Multi-Beam Echo-Sounder (MBES) systems. Two datasets were acquired at water depths of 10 m and 30 m with three pulse lengths equaling 27 s , 54 s , and 134 s in the Oosterschelde estuary (The Netherlands). The comparison between the bathymetric uncertainties derived from the measurements and those predicted using the current model indicated a relatively good agreement except for the most outer beams. The performance of the uncertainty prediction model improved by accounting for the most recent insights into the contributors to the MBES depth uncertainties, i.e., the Doppler effect, baseline decorrelation (accounting for the pulse shape), and the signal-to-noise ratio.
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Arief, Muchlisin, Maryani Hastuti, Wikanti Asriningrum, Ety Parwati, Syarif Budiman, and Teguh Prayogo. "PENGEMBANGAN METODE PENDUGAAN KEDALAMAN PERAIRAN DANGKAL MENGGUNAKAN DATA SATELIT SPOT-4. STUDI KASUS: TELUK RATAI, KABUPATEN PESAWARAN." Jurnal Penginderaan Jauh dan Pengolahan Data Citra Digital 10, no. 1 (2013): 1–14. https://doi.org/10.30536/inderaja.v10i1.3267.
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Bathymetric estimation of shallow water depth using satellite remote sensing data becomes more prevalent. However, when these methods are implemented for areas with different environments, the results indicate the presence of irregularities. To minimize the deviation, conducted the merger of the information obtained from field measurements with reflectance values SPOT-4 satellite imagery. This paper proposed the method development for bathymetric estimation of shallow water depth based on the correlation function between the depth value of direct measurements using a "handheld echo-sounder" to the resultant of reflectance values (band 1 and band 3). The algorithm for bathymetric estimation of a shallow water depth consists of thresholding method and correlation functions. Threshold value (T) depth of 0.5 meters is determined from observations of the correlation function graph polynomial from five and magnitude is 0.35 <T <0.47. Based on the results of the calculations show that the SPOT-4 satellite data can be used to estimate the shallow water depths up to approximately 18 meters.
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TÜKENMEZ, Emre, Emre GÜLHER, and Ozgur KAYA. "Comparison of Publicly Available Bathymetric Data with Real Measurements in the Southeastern Black Sea." International Journal of Environment and Geoinformatics 10, no. 3 (2023): 48–52. http://dx.doi.org/10.30897/ijegeo.1325607.
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Being able to access accurate and reliable depth information has uncountable benefits for not only fields of oceanography, geophysics, geology, natural resources but also navigation & logistics. There is an ever-increasing demand for high-resolution bathymetric data for those fields since only a small portion of the world seas and oceans have been explored, observed, and charted so far. There are some sources which provide publicly available global bathymetric data to its stakeholders and users such as widely used European Marine Observation and Data Network (EMODnet) and General Bathymetric Chart of the Oceans (GEBCO). In general, it is challenging for researchers to select the best fit for their studies among available datasets, due to the fact that their sole reliability is not well-assessed. The purpose of our study, thus, is to compare those publicly available bathymetric data with field measurements obtained from the surveys carried out by the Office of Navigation, Hydrography and Oceanography for an area of interest in the southeastern Black Sea comprising various characteristics as to the bottom topography (i.e. homogeneous elevation, steep slope, mild slope, etc.). Validation is conducted focusing on these distinct features by means of visual assessment and quantitative comparison. Results reveal that, even though there is an overall agreement, local discrepancies are also present. Nonetheless, GEBCO and EMODnet datasets are proved to be great assets for any hydrospatial application that does not necessarily require high spatial resolution.
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Alevizos, Evangelos. "Quantification of Nearshore Sandbar Seasonal Evolution Based on Drone Pseudo-Bathymetry Time-Lapse Data." Remote Sensing 16, no. 23 (2024): 4551. https://doi.org/10.3390/rs16234551.
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Nearshore sandbars are dynamic features that characterize shallow morphobathymetry and vary over a wide range of geometries and temporal lifespans. Nearshore sandbars influence beach geometry by altering the energy of incoming waves; thus, monitoring the evolution of sandbars is a fundamental approach in effective coastal planning. Due to several natural and technical limitations related to shallow seafloor mapping, there is a significant gap in the availability of high-resolution, shallow bathymetric data for monitoring the dynamic behaviour of nearshore sandbars effectively. This study introduces a novel image-processing technique that produces time series of pseudo-bathymetric data by utilizing multi-temporal (monthly) drone imagery, and it provides an assessment of local morphodynamics at a sandy beach in the southeast Mediterranean. The technique is called standardized-ratio bathymetric index (SRBI), and it transforms natural-colour drone imagery to pseudo-bathymetric data by applying an empirical formula used for satellite-derived bathymetry. This technique correlates well with laser altimetry depth measurements; however, it does not require in situ depth data for implementation. The resulting pseudo-bathymetric data allows for extracting cross-shore profiles and delineating the sandbar crest with 4 m horizontal accuracy. Stacking of temporal profiles allowed for the quantification of the sandbar’s crest and trough changes at different alongshore sections. The main findings suggest that the nearshore crescentic sandbar at Episkopi Beach (north Crete) shows strong seasonality regarding net offshore migration that is promoted by enhanced wave action during winter months. In addition, the crescentic sandbar is susceptible to morphology arrestment during prolonged weeks of low wave action. The average migration rate during winter is 10 m.month−1, with some sections exhibiting a maximum of 60 m.month−1. This study (a) offers a novel remote-sensing approach, suitable for nearshore seafloor monitoring with low computational complexity, (b) reveals sandbar geometry and temporal change in superior detail compared to other observational methods, and (c) advances knowledge about nearshore sandbar monitoring in the Mediterranean region.