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Correction Mar. Geod. (IF 1.6) Pub Date : 2024-03-11
Published in Marine Geodesy (Ahead of Print, 2024)
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GNSS-supported direct georeferencing for UAV photogrammetry without GCP in Antarctica: a case study in Larsemann Hills Mar. Geod. (IF 1.6) Pub Date : 2024-03-01 Leyue Tang, Gang Qiao, Bofeng Li, Xiaohan Yuan, Haibo Ge, Sergey Popov
Unmanned aerial vehicle (UAV) has become an increasingly popular remote sensing platform in Antarctica. Due to the challenging natural conditions and lack of global navigation satellite system (GNS...
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A Backscatter Model Combing Wind and Rain Effect at Low Incidence Angles Mar. Geod. (IF 1.6) Pub Date : 2024-02-15 Xiaojun Qu, Zhuang Liu, Hao Li
As the Wind blows over the ocean surface, the generated waves are the primary factor affecting the microwave backscatter of the remote sensing radar. In addition, there are also some influencing fa...
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GNSS-A Network Solution with Zenith Acoustic Delay Estimation Mar. Geod. (IF 1.6) Pub Date : 2024-01-30 Shuqiang Xue, Yuanxi Yang, Wenlong Yang, Jingsen Li
The ocean sound speed changes drastically with time and space. It is almost impossible to achieve centimeter-level-precision Global Navigation Satellite System (GNSS)-Acoustic (GNSS-A) positioning ...
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Effect of atmospheric corrections on shallow sea bathymetric mapping using gaofen-2 imagery: a case study in Lingyang Reef, South China Sea Mar. Geod. (IF 1.6) Pub Date : 2024-01-16 Tianqi Lu, Yan Yu, Luyi Wang, Wei Chen, Caiying Ji, Xiang Tang, Changgao Shao
Satellite-derived bathymetry (SDB) with high spatial resolution effectively maps detailed information about shallow sea depths. Properly selecting atmospheric correction (AC) methods is crucial to ...
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Detecting outliers in crowdsourced bathymetric data based on intelligently optimized 3D-DBSCAN algorithm Mar. Geod. (IF 1.6) Pub Date : 2024-01-16 Shuaidong Jia, Hao Yuan, Lihua Zhang, Zhicheng Liang, Zhou Yinfei
To address the problem of low quality of the outlier detection results caused by the irregular spatial distribution of crowdsourced bathymetric data, an intelligently optimized 3D-DBSCAN method is ...
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Global Sea Level Change Rate, Acceleration and Its Components from 1993 to 2016 Mar. Geod. (IF 1.6) Pub Date : 2024-01-16 Fengwei Wang, Yunzhong Shen, Qiujie Chen, Jianhua Chen, Jianhua Geng
Investigating the global sea level budget is essential to quantify the total sea level change (altimetry) and its components, including the steric sea level change and the ocean mass change (gravit...
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A Case-Based Reasoning Method for Generalizing Depth Contours considering Both Navigational Safety Assurance and Line Shape Preservation Mar. Geod. (IF 1.6) Pub Date : 2024-01-16 Shuaidong Jia, Zikang Song, Lihua Zhang, Zhicheng Liang
To address the problem that the parameters are relatively fixed in the existing automatic methods of depth contour generalization, a case-based reasoning method for generalizing depth contours is p...
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Vortex-induced vibration effects in underwater acoustic wireless sensor networks Mar. Geod. (IF 1.6) Pub Date : 2024-01-08 Tippireddy Srinivasa Reddy, Rajeev Arya, Prateek
A randomly fluctuated vortex-induced vibration (VIV) affects the localization of moving targets in an underwater acoustic wireless sensor network (UAWSN) to cause an offset time and time synchroniz...
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Wet Tropospheric Correction for the HY-2C Altimeter over the Coastal Ocean Based on GNSS and ERA5 Data Mar. Geod. (IF 1.6) Pub Date : 2024-01-02 Jie Sun, Jungang Yang, Wei Cui, Ruifu Wang, Xinrui Jiang
For the impact of land, sea ice, rainfall and strong wind, the wet tropospheric correction (WTC) of HY-2C (the third marine dynamic environmental monitoring satellite of China) altimeter cannot be ...
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Spline retracker: a geometrical retracking algorithm for coastal and open ocean altimetry Mar. Geod. (IF 1.6) Pub Date : 2024-01-02 Saleh Mafi, Saeed Farzaneh, Mohammad Ali Sharifi, Ehsan Forootan
Satellite altimetry has enhanced the understanding of ocean dynamics through high-rate sampling and global coverage. However, land contamination and bad reflection effects limit its accuracy. We pr...
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Coastal vulnerability assessment along the coast of Kerala, India, based on physical, geological, and socio-economic parameters Mar. Geod. (IF 1.6) Pub Date : 2023-12-11 Saikrishnan K., Anand K.V., Agilan V.
The increase in population and rapid economic development activities increase vulnerability along the coastal areas. Coastal zones are among the planet’s most dynamic regions and are susceptible to...
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Inversion Method for Instantaneous SSP Area Difference Mar. Geod. (IF 1.6) Pub Date : 2023-11-22 Wenzhou Sun, Yuanxi Yang, Anmin Zeng
Addressing the challenge of real-time estimation of instantaneous sound speed profiles (SSP for short). We proposes a SSP inversion method based on the travel time of vertically launched sound wave...
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Validation of the Total Suspended Matter (TSM) algorithm using in situ datasets over the Bay of Bengal Coastal Water Mar. Geod. (IF 1.6) Pub Date : 2023-08-25 Bimalkumar Patel, Apurva Prajapati, Ranjit Kumar Sarangi, Bhargav Devliya, Hitesh Patel
TSM (Total suspended matter) is important metric because it influences ocean biogeochemistry and seaweed habitat. Light penetration is influenced by the TSM range, which is linked to primary produc...
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Automatic Collision Avoidance Route Planning Method in Complex Navigation Environments Mar. Geod. (IF 1.6) Pub Date : 2023-08-08 Yinfei Zhou, Lihua Zhang, Shuai Dong Jia, Zeyuan Dai, Junnan Liu
Efficient collision avoidance (CA) route planning is one of the important technologies for ensuring the safety of autonomous ships. Many CA route planning studies have been developed for the open s...
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Calibration of the Instrumental Errors on Marine Gravity Recovery from SWOT Altimeter Mar. Geod. (IF 1.6) Pub Date : 2023-07-19 Gang Ma, Taoyong Jin, Pengyuan Jiang, Jiasheng Shi, Mao Zhou
The wide-swath altimetry mission, Surface Water and Ocean Topography (SWOT), makes it possible to further break through the accuracy and resolution of marine gravity field recovery. However, as its...
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Estimation of the Sea State Bias Using the Interpolation Method and Applications to Inter-Mission Calibration Mar. Geod. (IF 1.6) Pub Date : 2023-07-04 Alexa Putnam, Shailen D. Desai, R. Steven Nerem
An alternative approach to empirical, non-parametric sea state bias (SSB) modeling for satellite altimeter measurements was developed with the intention of providing a simple, transparent, and effi...
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Precise Navigation of USV Based on PPP-RTK/MEMS in the Offshore Environment Mar. Geod. (IF 1.6) Pub Date : 2023-06-19 Minzhi Xiang, Hongzhou Chai, Xiao Yin, Zhenqiang Du, Kaidi Jin
Abstract High-precision position, velocity and attitude information is the premise for the unmanned surface vehicle (USV) to perform various tasks. The traditional navigation technology of USV is to combine RTK (real-time kinematics) with MEMS (micro-electromechanical system). In order to avoid bi-directional communication of RTK/MEMS, a loosely coupled PPP (precise point positioning)-RTK/MEMS navigation
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Estimation of the sea state bias error budget for pulse-limited satellite altimetry Mar. Geod. (IF 1.6) Pub Date : 2023-06-19 Alexa Putnam, Shailen D. Desai, R. Steven Nerem
Abstract Using an empirical, non-parametric sea state bias (SSB) modeling method, which was developed as a tool for SSB error analysis (Putnam, Alexa Forthcoming), we provide an error budget for overall SSB error, as well as the contributing sources of this error budget. The error analysis compares methods used to derive SSB models from observed altimeter measurements, collinear differences of measurements
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Low-cost multi-GNSS, single-frequency RTK averaging for marine applications: accurate stationary positioning and vertical tide measurements Mar. Geod. (IF 1.6) Pub Date : 2023-05-29 Emily Tidey, Robert Odolinski
Abstract The use of Real Time Kinematic (RTK) Global Navigation Satellite System (GNSS) for accurate horizontal and vertical measurements in the marine environment has been considered since the late-1980’s and tested from the 1990’s when GPS and GLONASS were the only operational constellations available and high-cost multi-frequency receiver equipment was required. This paper modernizes the conversation
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A GNSS-aided DVL calibration method based on quaternion estimation for underwater vehicles Mar. Geod. (IF 1.6) Pub Date : 2023-05-27 Kaidi Jin, Hongzhou Chai, Chuhan Su, Minzhi Xiang, Mingchen Shi
Abstract Doppler velocity logger (DVL) error parameters can significantly influence the navigation accuracy of DVL/strapdown inertial navigation system (SINS) integration for unmanned underwater vehicles (UUV). To improve the navigation accuracy of UUV, this study proposes a two-stage DVL calibration method aided by global navigation satellite system (GNSS) measurements. First, utilizing the velocity
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Multispectral Satellite-Derived Bathymetry Based on Sparse Prior Measured Data Mar. Geod. (IF 1.6) Pub Date : 2023-05-23 Yanhong Wang, Yilan Chen, Yikai Feng, Zhipeng Dong, Xiaoyu Liu
Abstract Satellite-derived bathymetry is an economic and effective method of obtaining large-scale, high-resolution bathymetric information. At present, bathymetric inversion models require existing bathymetric data as a necessary condition, but these may be difficult to obtain around many small islands. Under the condition of sparse measurement data, many common methods have low levels of accuracy
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Distinguishing Ulva prolifera and Sargassum horneri by using multi-feature-based ResUnet algorithm Mar. Geod. (IF 1.6) Pub Date : 2023-05-03 Jinyu Li, Shengjia Zhang, Chao Zhang, Hongchun Zhu
Abstract In recent years, two types of macroalgae, namely, Ulva prolifera and Sargassum horneri, have appeared occasionally together in the Yellow Sea and the East China Sea. Remote sensing enables timely and cost-effective observation of macroalgae across large areas. In the available studies, the recognition and classification of the two macroalgae are primarily based on spectral difference analysis
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Assessment of beach morphological changes in the east coast of India during cyclone Phethai, through field data and numerical modeling Mar. Geod. (IF 1.6) Pub Date : 2023-04-27 V. Noujas, R. S. Kankara, B. Rajan
Abstract Episodic extreme waves caused by cyclones can have catastrophic consequences for coastal zones, including drastic beach morphology changes. The present study analyzed the beach morphological changes from Kakinada to Konapapapeta on the southeast coast of India before, during, and after the tropical cyclone Phethai using field survey and numerical modeling. Beach profiles were collected using
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Probabilities of acquiring cloud-free and low-tide Landsat observations for mapping saltmarsh over south-eastern Bangladesh from 1980 to 2019 Mar. Geod. (IF 1.6) Pub Date : 2023-04-17 Sheikh Mohammed Rabiul Alam, Mohammad Shawkat Hossain
As is well-documented, cloud cover (CC) obscures the target object and water depth and turbidity impede optical remote sensing (RS). Therefore, Landsat imagery acquired under cloud-free (CFI) and l...
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High-resolution seafloor survey and applications Mar. Geod. (IF 1.6) Pub Date : 2023-04-08 Rongxing (Ron) Li
Published in Marine Geodesy (Vol. 46, No. 3, 2023)
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Estimating the Wind Dependency of Aerosol Optical Depth at Remote Oceanic Regions Mar. Geod. (IF 1.6) Pub Date : 2023-03-08 Debojyoti Ganguly, Mini Raman
Abstract In this article, the applicability of India’s indigenously developed scatterometer, Scatsat-1 for marine aerosol characterization and wind dependency of aerosol optical depth (AOD) was investigated using 3 years of satellite data. Wind data from Scatsat-1 and AOD with its size fraction from SNPP VIIRS from 2017 to 2019 were used for the investigation. A technique has been demonstrated for
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Improving the accuracy of bathymetry using the combined neural network and gravity wavelet decomposition method with altimetry derived gravity data Mar. Geod. (IF 1.6) Pub Date : 2023-02-27 Yongjin Sun, Wei Zheng, Zhaowei Li, Zhiquan Zhou, Xiaocong Zhou, Zhongkai Wen
Abstract The wide range of bathymetry models can be estimated using the marine gravity information derived from satellite altimetry. However, due to nonlinear factors influences such as isostasy effects, the bathymetry estimated by gravity anomaly and vertical gravity gradient is not satisfactory. Therefore, to improve the accuracy of bathymetry estimation, a combined neural network and gravity information
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The impact of nonlinear tide–surge interaction on satellite radar altimeter-derived tides Mar. Geod. (IF 1.6) Pub Date : 2023-02-20 H. Guarneri, M. Verlaan, D. C. Slobbe, J. Veenstra, F. Zijl, J. Pietrzak, M. Snellen, L. Keyzer, Y. Afrasteh, R. Klees
Abstract Both empirical and assimilative global ocean tidal models are significantly more accurate in the deep ocean than in shelf and coastal waters. In this study, we answered whether this is due to the quality of the models used to reduce tide and surge or the general approach to treat tide and surge as two separate components of the water level obtained from stand-alone models, which ignores the
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Aggregation Methods Using Bathymetry Sources of Differing Subjective Reliabilities for Navigation Mapping Mar. Geod. (IF 1.6) Pub Date : 2023-02-06 Paul Elmore, Brian Calder, Fred Petry, Giuseppe Masetti, Ron Yager
Abstract When planning for ship navigation or compiling data for a bathymetry map, the navigator or mapper uses many different sources of bathymetry information and navigation hazards. The quality of these sources is inconsistent in general, however, making it challenging to provide a coherent picture for planning. Here, we describe an approach for consistent planning/mapping that uses a combination
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Augmented Underwater Acoustic Navigation with Systematic Error Modeling Based on Seafloor Datum Network Mar. Geod. (IF 1.6) Pub Date : 2023-01-02 Junting Wang, Tianhe Xu, Yangfan Liu, Mowen Li, Long Li
Abstract Underwater acoustic navigation technology is an important approach to achieving high precision ocean navigation. One of the critical issues of the technology is to correct systematic errors, which are related to time delays and time-varying sound speed errors. In this study, we propose an augmented underwater acoustic navigation with systematic error model based on seafloor datum network.
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Two-Stage Learning Model-Based Angle Diversity Method for Underwater Acoustic Array Mar. Geod. (IF 1.6) Pub Date : 2022-12-12 Yu Zhang, Dan Zhang, Zhen Han, Peng Jiang
Abstract The diversity combining technique performs well in the inhibition of multipath, it has been widely used in underwater acoustic (UWA) array signal processing. However, the underwater noise can seriously affect the processing results of the diversity. The conventional filtering algorithms cannot deal with the nonlinear components of underwater radiation noise and have a poor processing effect
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Foreword Mar. Geod. (IF 1.6) Pub Date : 2022-11-26 Yuanxi Yang, Tianhe Xu, Shuqiang Xue
Published in Marine Geodesy (Vol. 46, No. 1, 2023)
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The 2019 East Coast Slow Slip Event, New Zealand: Spatiotemporal Evolution and Associated Seismicity Mar. Geod. (IF 1.6) Pub Date : 2022-11-08 Lupeng Zhang, Dingfa Huang, C. K. Shum, Rumeng Guo
Abstract Slow slip events (SSEs) are interpreted as the transient quasi-static fault deformation in the deep transition zone from locked to freely slipping in many subduction zones. Using continuous Global Positioning System (cGPS) data collected in New Zealand, we estimate the spatiotemporal evolution model during the 2019 SSE and analyze the influence of subduction interface heterogeneity on seismicity
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A new mesoscale eddy tracking methodology based on fast normalized cross-correlation and its validation in the Northwest Pacific Mar. Geod. (IF 1.6) Pub Date : 2022-10-21 Gengming Zhang, Lei Zhang, Song Li, Bin Xue, Weishuai Xu
Abstract Most mesoscale eddy tracking methodologies used prior to this study evaluated eddy features using a distance-based proximity relationship, rather than considering similarities between eddies. This study applies a fast normalized cross-correlation methodology in the field of image registration to propose a novel mesoscale eddy tracking methodology that can rapidly and comprehensively calculate
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Comparison of Six Empirical Methods for Multispectral Satellite-derived Bathymetry Mar. Geod. (IF 1.6) Pub Date : 2022-10-21 Sensen Chu, Liang Cheng, Jian Cheng, Xuedong Zhang, Jinming Liu
Abstract Satellite-derived bathymetry (SDB), an important technology in marine geodesy, is advantageous because of its wide coverage, low cost, and short revisit cycle. At present, several different kinds of SDB methods exist, and their inversion accuracy is affected by algorithm performance, band selection, and sample distribution, among other factors. But these factors have not been adequately quantified
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Compilation of the new detailed geoid model HKGEOID-2022 for the Hong Kong territories Mar. Geod. (IF 1.6) Pub Date : 2022-09-25 Albertini Nsiah Ababio, Robert Tenzer
Abstract Number of detailed geoid models have been developed to convert geodetic heights measured by the Global Navigation Satellite Systems (GNSS) to heights in the Hong Kong Principal Datum (HKPD). Although gravity measurements were used to compile these geoid models, heights of leveling benchmarks in HKPD were determined from precise spirit leveling measurements but without involving gravity data
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Development of Total Suspended Matter (TSM) Algorithm and Validation over Gujarat Coastal Water, the Northeast Arabian Sea Using In Situ Datasets Mar. Geod. (IF 1.6) Pub Date : 2022-09-06 Bimalkumar Patel, Ranjit Kumar Sarangi, Apurva Prajapati, Bhargav Devliya, Hitesh Patel
Abstract TSM is an essential parameter as it affects the biogeochemistry of the ocean. The high TSM range affects light penetration that’s related to the photosynthesis of primary producers. The aim is to develop a TSM algorithm in Gujarat coastal water using remote sensing reflectance (Rrs), to monitor TSM concentration from the satellite. Seawater sampling and HyperOCR radiometer data collection
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Tidal Level Prediction Using Combined Methods of Harmonic Analysis and Deep Neural Networks in Southern Coastline of Iran Mar. Geod. (IF 1.6) Pub Date : 2022-08-28 Kourosh Shahryari Nia, Mohammad Ali Sharifi, Saeed Farzaneh
Abstract Predicting tides and water levels had always been such an important topic for researchers and professionals since the study of tidal level has pivotal role in supporting marine economy, port construction projects and maritime transportation. Tidal water levels are a combination of astronomical (deterministic part) and non-astronomical (stochastic part) water levels. In this study, we combined
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A Robust Method to Estimate the Coordinates of Seafloor Stations by Direct-Path Ranging Mar. Geod. (IF 1.6) Pub Date : 2022-08-24 Xianping Qin, Yuanxi Yang, Bijiao Sun
Abstract The ranges derived from acoustic measurements between seafloor stations are relatively more accurate compared with those derived from the sea surface vessel transducer to the seafloor transponders, because measurements through mixed water layers will be affected by complex acoustic range errors. Coordinates of seafloor stations can be improved by the direct-path acoustic ranging. Systematic
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Lead Detection in the Arctic Ocean from Sentinel-3 Satellite Data: A Comprehensive Assessment of Thresholding and Machine Learning Classification Methods Mar. Geod. (IF 1.6) Pub Date : 2022-07-08 Inger Bij de Vaate, Ericka Martin, D. Cornelis Slobbe, Marc Naeije, Martin Verlaan
Abstract In the Arctic Ocean, obtaining water levels from satellite altimetry is hampered by the presence of sea ice. Hence, water level retrieval requires accurate detection of fractures in the sea ice (leads). This paper describes a thorough assessment of various surface type classification methods, including a thresholding method, nine supervised-, and two unsupervised machine learning methods,
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Extracting Coastal Water Depths from Multi-Temporal Sentinel-2 Images Using Convolutional Neural Networks Mar. Geod. (IF 1.6) Pub Date : 2022-07-05 Yustisi Lumban-Gaol, Ken Arroyo Ohori, Ravi Peters
Abstract Satellite-Derived Bathymetry (SDB) can be calculated using analytical or empirical approaches. Analytical approaches require several water properties and assumptions, which might not be known. Empirical approaches rely on the linear relationship between reflectances and in-situ depths, but the relationship may not be entirely linear due to bottom type variation, water column effect, and noise
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Analytical Method for High-Precision Seabed Surface Modelling Combining B-Spline Functions and Fourier Series Mar. Geod. (IF 1.6) Pub Date : 2022-06-29 Ruichen Zhang, Guojun Zhai, Shaofeng Bian, Houpu Li, Bing Ji
Abstract High-accuracy seabed surface modelling provides multi-source high-precision fundamental geographic datasets for marine visual computing, seabed topography detection, marine biology, marine engineering and other fields. Proposed in this paper is a high-precision seabed surface model, which combines B-spline functions and Fourier-series, referred to as the Spline-Fourier-series (S-FS) method
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Hydrodynamic Modelling of Storm Surge with Modified Wind Fields along the East Coast of India Mar. Geod. (IF 1.6) Pub Date : 2022-06-02 Rohini Selvaraj, Sannasiraj S. A., Sundar Vallam
Abstract Propagation of tropical cyclones and their landfall along the coast affect the livelihood of the coastal community with loss of life, and Bay of Bengal is particularly vulnerable as past disasters have shown. The present study investigates the effects of tropical cyclones namely Phailin, Hudhud and Vardah during its landfall along the East Coast of India. Numerical modelling of storm surges
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A Self-Constraint Underwater Positioning Method without the Assistance of Measured Sound Velocity Profile Mar. Geod. (IF 1.6) Pub Date : 2022-05-27 Jianhu Zhao, Wenbiao Liang, Jinye Ma, Meiqin Liu, Yuqing Li
Abstract Aiming at the problem that lack of the measured sound velocity profile (SVP) leads to the unreliable underwater positioning solution, this paper proposed an efficient underwater positioning method by the self-constraint conditions of water depth and sound velocity gradient. To construct the depth constraint condition, the sound propagation distance error model is deduced by acoustic ray tracing
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An Empirical Study of the Influence of Seafloor Morphology on the Uncertainty of Bathymetric Data Mar. Geod. (IF 1.6) Pub Date : 2022-05-18 Willian Ney Cassol, Sylvie Daniel, Éric Guilbert, Nathalie Debese
Abstract The estimation of the uncertainty related to bathymetric data is essential in determining the quality of the data acquisition. This estimation is based on the covariance propagation considering the classical sounding georeferencing model. The estimation of the uncertainty using the Total Propagated Uncertainty (TPU) model is well described in the literature. Developing on this model, this
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Satellite Derived Bathymetry with Sentinel-2 Imagery: Comparing Traditional Techniques with Advanced Methods and Machine Learning Ensemble Models Mar. Geod. (IF 1.6) Pub Date : 2022-05-04 Tyler Susa
Abstract Accurate charting of nearshore bathymetry is critical to the safe and dependable use of coastal waterways frequented by the trading, fishing, tourism, and ocean energy industries. The accessibility of satellite imagery and the availability of various satellite-derived bathymetry (SDB) techniques have provided a cost-effective alternative to traditional in-situ bathymetric surveys. Furthermore
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Acoustic Ray-Trace Correction for UUVs Cooperative Localization in Deep Ocean Applications Mar. Geod. (IF 1.6) Pub Date : 2022-04-23 Zhenqiang Du, Hongzhou Chai, Zeyu Li, MinZhi Xiang, Fan Zhang, Jun Hui
Abstract Precise position of Unmanned Underwater Vehicles (UUVs) plays a decisive role in optimal formation control, reasonable path planning, and efficient cooperative operation. However, the traditional method has the deficiency of low ranging accuracy and contains systematic deviation in the deep ocean applications, which seriously affects the accuracy of UUVs position and makes the goal of UUVs
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Realization and Evaluation of Real-Time Uncombined GPS/Galileo/BDS PPP-RTK in the Offshore Area of China’s Bohai Sea Mar. Geod. (IF 1.6) Pub Date : 2022-04-04 Xiao Yin, Hongzhou Chai, Wenbing Xu, Liang Zhao, Huawei Zhu
Abstract The real-time kinematic (RTK) technology has been widely used as the high-precision positioning method in the offshore area. However, RTK requires a bi-directional communication and groups measurement errors together, thereby limiting its mass-market applications. Combining the advantages of precise point positioning (PPP) and RTK, PPP-RTK has become one of the hotspot technologies in the
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Framework for Automatic Coral Reef Extraction Using Sentinel-2 Image Time Series Mar. Geod. (IF 1.6) Pub Date : 2022-03-28 Qizhi Zhuang, Jian Zhang, Liang Cheng, Hui Chen, Yanruo Song, Song Chen, Sensen Chu, Shengkun Dongye, Manchun Li
Abstract Using supervised and unsupervised classification on a single image to extract coral reef extent results in missing data and wrong extraction results. To improve the accuracy of coral reef extraction, this study proposes a novel technical framework for automatic coral reef extraction based on an image filtering strategy and spatiotemporal similarity measurements of pixel-level Sentinel-2 image
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Improved Seafloor Geodetic Positioning via Sound Velocity Correction Based on the Precise Round-Trip Acoustic Positioning Model Mar. Geod. (IF 1.6) Pub Date : 2022-03-26 Dajun Sun, Miao Yu, Cuie Zheng, Yunfeng Han, Zongyan Li
Abstract Seafloor geodetic positioning is crucial for evaluating the marine geodetic network and monitoring various marine activities. We propose a sound velocity correction method based on the precise round-trip acoustic positioning model to improve the accuracy of seafloor geodetic positioning. The proposed method models the sound velocity error related to sound velocity profile (SVP) deviation and
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A Nonlinear Gauss-Helmert Model and Its Robust Solution for Seafloor Control Point Positioning Mar. Geod. (IF 1.6) Pub Date : 2022-03-26 Yingcai Kuang, Zhiping Lu, Fangchao Wang, Kaichun Yang, Linyang Li
Abstract Using GNSS-Acoustic (GNSS-A) technology to establish the seafloor geodetic datum is both feasible and flexible and thus has become an important way to obtain the absolute positions of seafloor control points. However, numerous errors are inevitable in marine surveying, including systematic errors and gross errors caused by GNSS dynamic positioning, inaccurate sound velocity profile measurements
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Effects of Offsets and Outliers on the Sea Level Trend at Antalya 2 Tide Gauge within the Eastern Mediterranean Sea Mar. Geod. (IF 1.6) Pub Date : 2022-03-11 Mehmet Emin Ayhan
Abstract Antalya 2 tide gauge (TG) station is located on the coast of Turkey within the Eastern Mediterranean Sea. Relative sea level trends 6.0 ± 1.5 and 6.44 ± 0.45 mm/year over 1985–2009 at Antalya 2 TG are different from the trend (1.6 ± 1.5 mm/year over 1935–1977) at Antalya TG within 10 km. In order to investigate this trend discrepancy, the monthly mean series at Antalya 2 TG is re-analyzed
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An Integrated Approach for Determining the Anthropogenic Stress Responsible for Degradation of a Ramsar Site – Wular Lake in Kashmir, India Mar. Geod. (IF 1.6) Pub Date : 2022-03-08 Saleha Jamal, Wani Suhail Ahmad, Uzma Ajmal, Md. Aaquib, Md. Ashif Ali, Md. Babor Ali, Shafiq Ahmed
Abstract During the last one and half decade, Kashmir valley's water bodies have been facing widespread water quality deterioration due to anthropogenic interferences' enhancement. In this context, the present study aims to monitor the water quality of Wular Lake by subjecting the acquired datasets to statistical approaches to infer status about distinctions and similarities among different sampling
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A Compensation Algorithm with Motion Constraint in DVL/SINS Tightly Coupled Positioning Mar. Geod. (IF 1.6) Pub Date : 2022-02-24 Kaidi Jin, Hongzhou Chai, Chuhan Su, Minzhi Xiang
Abstract Integration of strapdown inertial navigation system (SINS) and doppler velocity log (DVL) is usually applied in underwater applications, wherein DVL provides the three-dimensional velocity, and hence the accumulated error of SINS can be compensated. However, the DVL/SINS loosely coupled approach fails in the complex environments on the condition of fewer than three available beams. And the
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An Investigation of the Hydrography of Chabahar Bay Using FVCOM Model and EOF Analysis Mar. Geod. (IF 1.6) Pub Date : 2022-02-22 Alireza Bahmanzadegan Jahromi, Mojtaba Ezam, Kamran Lari, Abbas Ali Ali Akbari Bidokhti
Abstract Chabahar Bay is a semi-enclosed and shallow omega-shaped bay, located on the south-eastern coasts of Iran. The 3D unstructured-grid Finite-Volume Coastal Ocean Model was employed to study the physical characteristics of water in Chabahar Bay. The correlation coefficients between the model and available measurements were 0.99 and 0.84 for water level and current velocity, respectively. The
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A Multi-Source Convolutional Neural Network for Lidar Bathymetry Data Classification Mar. Geod. (IF 1.6) Pub Date : 2022-02-04 Yiqiang Zhao, Xuemin Yu, Bin Hu, Rui Chen
Abstract Airborne Lidar bathymetry (ALB) has been widely applied in coastal hydrological research due to outstanding advantages in integrated sea-land mapping. This study aims to investigate the classification capability of convolutional neural networks (CNN) for land echoes, shallow water echoes and deep water echoes in multichannel ALB systems. First, the raw data and the response function after
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Assessment of PRISMA Level-2 Hyperspectral Imagery for Large Scale Satellite-Derived Bathymetry Retrieval Mar. Geod. (IF 1.6) Pub Date : 2022-02-04 Evangelos Alevizos, Tim Le Bas, Dimitrios D. Alexakis
Abstract Currently, several satellite-derived bathymetry (SDB) workflows are based on a variety of satellite imagery which are analyzed by empirical or analytical methods. The latest availability of PRISMA hyperspectral data provides a new opportunity for testing their application in shallow water bathymetry mapping. Here we utilize two Level-2 PRISMA scenes from the Caribbean Sea capturing seafloor
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Precise Point Positioning with GNSS Raw Measurements from an Android Smartphone in Marine Environment Monitoring Mar. Geod. (IF 1.6) Pub Date : 2022-01-25 Nursu Tunalioglu, Taylan Ocalan, Ali Hasan Dogan
Abstract In the next generation, the use of dual-frequency Embedded GNSS Chipset in the smart devices, which will be widely used in engineering applications, has been used for the first time in Xiaomi Mi8. Considering this development dynamics, a kinematic test was carried out in the marine environment monitoring with a geodetic GNSS receiver and an android smartphone in Turkey Oyak Port. According
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Case Study: Rigorous Boresight Alignment of a Marine Mobile LiDAR System Addressing the Specific Demands of Port Infrastructure Monitoring Mar. Geod. (IF 1.6) Pub Date : 2022-01-11 Mohsen H. Shahraji, Christian Larouche
Abstract Accurate infrastructure monitoring of ports and harbors is a vital operation conducted by the port’s authority. To operate regularly in this highly dynamic environment, we explore the potential of the cutting-edge mobile LiDAR systems (MLS) mounted on a vessel. To generate a high-quality 3 D point cloud that would satisfy the expected accuracy required in the monitoring task, the LiDAR scanner