Towards Automation of Volunteered and Authoritative Bathymetric Data Comparisons for Reputation Analysis
LT Patrick J. Debroisse

Seafloor mapping data are used all over the world for many purposes. Large volumes of high-quality hydrographic data are required to create high-accuracy charts and bathymetric models required by national defense, resource management, shipping, and scientific interest groups, among others. However, across the world, the amount of high-quality data available is limited. Volunteered Bathymetric Information (VBI), otherwise known as crowd sourced bathymetry (CSB), is a relatively untapped data source that could be used in many ways such as filling data gaps and informing future data collection expeditions. Determining the quality of VBI has been historically difficult and time consuming, leading to limited use by hydrographic offices. Despite this, the International Hydrographic Organization continues to collect and store VBI in its Data Centre for Digital Bathymetry (DCDB).

Recent developments in VBI quality assessment have made the regular use of VBI more viable, however data discovery and acquisition is still a time-consuming and error-prone process that must be improved upon before automation is possible. Currently, data discovery is a manual process involving the use of multiple web interfaces to identify and download files of interest for a given study area. In a world of limited staff resources, automating this process will help to increase the speed with which VBI could be incorporated into bathymetric models and decision-making tools.

Herein, the design of an open source, Python-based tool called VBI Compare is described. VBI Compare automates the data discovery and acquisition phase of VBI quality analysis workflows and allows for VBI data reputation calculations to be initiated. As part of the data discovery process, VBI Compare ensures colocation of VBI and authoritative chart data and displays the data collected and processing status to the user in a simple status window.

Further, the functionality of VBI Compare is demonstrated by a case study in the Gulf of Maine, United States using NOAA National Bathymetric Source (NBS) as the source of authoritative data. This case study shows the use of VBI Compare to locate and collect required data, and feed it into CSB reputation calculation tools from csb-python from start to finish. This case study demonstrates the real-world utility of VBI Compare to a hydrographic office for VBI evaluation.

GO-MARIE, Bathymetry for Science, Greenland - 2022
Daniel Leite

A 30-day multibeam bathymetric survey was carried out within the scope of the interdisciplinary, multi-year science program GO-MARIE launched and managed by Ocean Research Project. The bathymetric mapping targeted fjords previously uncharted or with very little known soundings on board SRV MarieTharp, a repurposed 22-meter steel-hulled schooner.

Robust Estimation of Multiple Simultaneous Integration Errors from Underway Multibeam Data
Brandon Maingot

While standard procedures ensuring accurate multi-sensor integration within a multibeam system already exist, operators are still plagued by small periodic systematic residuals in data. The source of these errors has long been recognized as the result of imperfect definitions of offsets, alignments, latencies and sound speed between the sonar and auxiliary sensors. In isolation, and shallow water geometry, any one of these sources is easy to recognize. In the presence of multiple sources, however, the resulting pattern of residuals can confound simple analysis. Gross errors are usually immediately apparent, but small errors such as a few milliseconds of latency or decimeters of lever arm, can be hard to identify. Commonly residuals are the result of a combination of several small errors rather than just one. This presentation will briefly discuss the challenges and methods used to achieve system identification under such heterogeneity.

Field Observations of Momentary Liquefaction
Melissa Marry

Melissa will discuss her research which aims to observe momentary liquefaction in the nearshore environment using a novel pressure profiling instrument.

Sentinel Indicators of the Acoustic Environment in Coastal Gulf of Maine Habitats
Grant Milne

Rapidly changing conditions in the Gulf of Maine could create variation in the underwater acoustic propagation environments of coastal habitats. Knowledge of the propagation environment is essential for quantifying uncertainty in the performance of active remote sensing technologies, as well as for maintaining effective communication for marine life that depend on acoustic communication signals. The use of passive acoustic monitoring (PAM) and genetic metabarcoding of seawater samples, separately and combined, provide an opportunity to identify soundscape attributes and genetic signals to serve as sentinel indicators of the propagation environment. A sentinel indicator is a variable that can be measured and monitored that represents a system, process, or key component of the ecosystem that is sensitive to environmental pressures. By identifying sound sources, detecting biota, and predicting substrate composition which contribute to the ambient sound level or attenuation of sound waves, it may be possible to predict the acoustic propagation environment associated with particular coastal habitats. Over the summers of 2021-2022, acoustic recordings and water samples used for metabarcoding were collected along the Maine and New Hampshire coastlines from four different locations each containing a sand, macroalgae, and eelgrass site. These data are currently being analyzed to determine whether a greater amount of variation can be accounted for by the type of habitat or geographic location in which sites are located. The results of this investigation will guide future analyses to identify sentinel indicators of acoustic environments present in coastal Gulf of Maine waters.

Air-Sea Interaction Experiment at SUSTAIN
Shantanu Soumya

Multi-UUV Optical Communication System Design
Igor Vladimirov

Igor’s research topic is focused on development of a multi-UUV subsurface wireless communication system, capable of supporting 3+ unpiloted vehicles. Throughout this presentation he will cover a brief introduction to underwater optical communication systems and what it takes to design and deploy one. Key components will include underwater light propagation, basic circuit design, digital signal processing and communication protocols. Igor will also share a few test results collected over the summer and will discuss major challenges he's faced throughout this project.