Weddell Sea Depths Warming Five Times Faster than Elsewhere

Over the past three decades, the depths of the Antarctic Weddell Sea have warmed five times faster than the rest of the ocean at depths exceeding 2,000 metres. This was the main finding of an article just published by oceanographers from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI). In the article, they analyse an unprecedented oceanographic time series from the Weddell Sea and show that the warming of the polar depths is chiefly due to changed winds and currents above and in the Southern Ocean. In addition, the experts warn that the warming of the... (read more)
2020-10-27 08:57:39

Applying Side-scan Sonar and an AI-powered Platform for Environmental Protection

Over the past few years, the University of Delaware, USA, has participated in a state programme which supports rescuing abandoned crab pots from the seabed and researches technologies to make the search process more effective. It has developed advanced sonar surveys from a boat with further map storage and processing in SPH Engineering’s ATLAS AI-powered platform. The evaluations proved to be time-effective and more accurate in comparison to the detections of human annotators.  Blue crab fishing is a popular commercial and recreational activity throughout the United States. In order to catch these crabs, people use 'crab pots'. These devices are placed... (read more)
2020-10-19 08:42:35

Bathymetry from UAV Imagery and Machine Learning

Improving Results with Refraction Corrections
Accurate bathymetric mapping of shallow areas is essential for a plethora of offshore activities. Through Structure from Motion (SfM) and Multiview Stereo (MVS) techniques, images can provide a low-cost alternative compared to Lidar and sonar systems while also offering important visual information. This article presents a new framework for mapping the seabed in clear and calm shallow waters for small- and large-scale surveys using aerial imagery and machine learning to correct the geometric effects of refraction on the 3D point clouds and the imagery. SfM is a photogrammetric technique for estimating 3D structures from 2D image sequences. It involves acquiring... (read more)
2020-10-13 10:42:39

Venezuela Performs Bathymetric Surveys with Own Satellite

Ever since the launch of the VRSS-2 Antonio José de Sucre satellite in 2017, researchers have been looking into how best to use and apply the information that it provides for the benefit of environmental development and sustainability. For example, the bathymetry derived from satellite images is very beneficial for hydrographic services, since it allows information to be obtained that has not been explored with traditional acoustic methods. The Venezuela Hydrographic Office has started to use this method, also to improve its hydrographic coverage. The Antonio José de Sucre satellite is Venezuela's third artificial satellite. It was launched from the Jiuquan... (read more)
2020-10-07 11:06:14

IHO Releases New Standards for Hydrographic Surveys

Earlier this month, the IHO released a new edition of the Standards for Hydrographic Surveys (S-44). In addition to surveys to support the safety of navigation, these standards can be adapted for oil and gas, renewable energies, dredging, geophysics and geotechnics. By clarifying the required levels of accuracy, they will help define the requirements in terms of technology, time and human resources and will save valuable resources. One of the notable changes in this latest version is the introduction of a new, more stringent classification for surveys called 'Exclusive Order', which expands the standards' applicability. This is designed for specific... (read more)
2020-10-05 08:51:31

Automatic Calibration for MBES Offsets

A New Way to Monitor Your Data
Currently, calibration of MBES for hydrographic surveys is based on the traditional ‘patch test’ method. This subjective method, although rigorous, has major drawbacks, such as being time-consuming (both data acquisition and processing) and supposing that potential angle misalignments can be considered as uncoupled. A new algorithmic solution, providing an objective and repeatable first step to the automation of the calibration process, is offered through the MSPAC solution. Hydrography is essential in many marine activities: Ensuring navigational safety for nautical charts and dredging. Acquiring accurate knowledge of environmental background for offshore installations and dredging. Modelling the seabed for marine energy prospection.... (read more)
2020-09-29 10:45:33

Russian Survey Vessel Explores 14,000km Cable Route across Arctic Seabed

On 6 August 2020, the Professor Logachev survey ship set out from Kirkenes, Norway on course for Russian Arctic waters. Over the next three months, the ship and its crew will sail 6,500km along the north Russian coast. The Norwegian border town could become a hub for an almost 14,000km-long telecom cable between Asia and Europe. Researchers are this summer exploring the best route across the Arctic seabed. Their mission is to look into the deep to examine the sea bottom. Their findings will be crucial for the future of Arctic Connect, the project developed by the Finnish company Cinia... (read more)
2020-09-04 01:29:59

Finnish Diving Team Discovers Rare Wreck of 17th-century Dutch Merchant Ship

While undertaking documentation dives on some supposedly World War I or II wrecks at the mouth of the Gulf of Finland, Badewanne divers descended on one of the biggest surprises during their long careers of diving the wrecks of this eastern extension of the Baltic Sea. The Baltic Sea has been an important trade route since the Middle Ages, as the navies of Holland and England needed endless supplies of wood, tar and hemp, all of which were available around the Baltic. From the 13th century onwards, the Hanseatic League controlled the trade, but during the 17th century the very... (read more)
2020-08-28 02:00:30

ASL to Perform Hydroacoustic Studies of Eulachon Fish Distribution

ASL Environmental Sciences (ASL) was chosen by Hemmera Envirochem Inc. and the Vancouver Fraser Port Authority to perform a hydroacoustic study of eulachon fish (Thaleichthys pacificus) distribution in the vicinity of Deltaport Terminals off the mouth of the Fraser River, BC, Canada. To support the development of the Dredging and Sediment Discharge Plan that will form part of the Construction Environmental Management Plan of the Roberts Bank Terminal 2 Project, the port authority has committed to developing eulachon-specific mitigation that will be used during dredging activities. A pilot study was developed to examine the efficacy of hydroacoustic techniques in detecting... (read more)
2020-08-24 10:53:16

Bathymetry and the Power of Sound

How a Single Device Can Change Our Understanding of the Depths Below Us
The single-beam echosounder has come a long way. First developed in the early 20th century in response to the RMS Titanic disaster of 1912, early models used a Fessenden oscillator to generate a signal of around 1kHz. The resulting broad beam was suitable for depth measurements and the location of large targets – a huge technological step forward – but incapable of the fine resolutions required to gain information as to the nature of the seabed. Jump forward a little over a century and the picture is very different. Advanced systems, working across multiple frequencies, can operate with beam widths as... (read more)
2020-08-18 08:35:03
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