As it Was

by a not so old Hydrographer
"Land in sight", a cry soon to be followed by "Clew up the main", to reduce speed. It is 1606 as the Dutch ship Duyfken makes first recorded landfall in Australia. But this is not simply landfall: Duyfken, under the command of Willem Janszoon, charts the first 200NM of the Great Southland: Australia. During this exploration of the East Coast of the Cape York Peninsula contact was also made with local Aboriginal people. The Dutch, as sixteenth-century European traders and carriers of goods such as grain and herring from the Baltic and salt and spices from the Iberian peninsular, fought... (read more)
2008-01-01 01:00:00

Unravelling the Ridge and Rift

Missed Opportunities and Triumph
Following Maurice Ewing’s first cruise to the Mid-Atlantic Ridge, two more were made by the end of the 1940s. The first of these was led by Ewing while the second was led by Bruce Heezen. Although Gunter Dietrich’s paper was referred to in the 1949 paper by Ivan Tolstoy and Ewing (see part I in last issue), neither seems to have comprehended its significance as he reported in the November 1949 National Geographic magazine: “Crossing the ridge, we drew a detailed profile of its peaks with our fathometer. Flanking the central highlands, we found deep trenches separating the main Ridge... (read more)
2014-10-15 02:53:21

Underwater Noise Monitoring in the North Sea

Jomopans Project to Monitor Continuous Sound
Sound is of vital importance for marine animals. Eleven institutes from the countries bordering the North Sea have joined forces in the Jomopans project to implement a novel monitoring strategy for underwater sound. Due to the growth of human activities in the sea, sound pollution is a growing concern for marine environmental managers. High levels of anthropogenic noise disturb animals, but the integrated impact of noise on the marine ecosystem is largely unknown. In the Joint Monitoring Programme of Ambient Noise in the North Sea (Jomopans) project, measurements at sea are combined with noise maps from numerical modeling to assess the quantitative levels of sound at sea. Sound is of vital importance for marine animals. Eleven institutes from the countries bordering the North Sea have joined forces in the Jomopans project to implement a novel monitoring strategy for underwater sound. Due to the growth of human activities in the sea, sound pollution is a growing concern for marine environmental managers. High levels of anthropogenic noise disturb animals, but the integrated impact of noise on the marine ecosystem is largely unknown. In the Joint Monitoring Programme of Ambient Noise in the North Sea (Jomopans) project, measurements at sea are combined with noise maps from numerical modeling to assess... (read more)
2019-06-18 04:01:43

Gold, Glory, and — HYDRO!

This month marks the 555th anniversary of the death of Prince Henry of Portugal, known as the Navigator, on 13 November 1460. Henry had set in motion a series of events that led to a new understanding of the earth, the discovery of the Americas, and on a darker note, the African slave trade. One month short of thirty-two years after his death, Christopher Columbus landed on a small island of the Bahamas. Henry was driven ‘To discover what lay beyond the Canaries and Cape Bojador; ...to fulfil the predictions of his horoscope, which bound him to engage in great... (read more)
2015-12-01 09:08:42

Hydro Dam Inspection by ROVs

The inspection and maintenance of vital resource facilities is an integral part of any regional health and stability management programme. Providing consistent quality output whilst reducing inspection and maintenance costs is key for those involved in the provision of such services, and requires the monitoring and assessment of relevant new technologies and techniques. By Rob Berlijn, HydroConsult, The Netherlands Over the past forty years Remote Operated Vehicles have become a well-proven component of basic toolkits for getting work done under-water in a wide variety of industrial, scientific, military and law-enforcement activities. In many cases the impetus behind adopting and evolving... (read more)
2008-01-01 01:00:00

Bio-inspired Underwater Robotics

Swimming, Swarming and Sensing
For operations in complex underwater environments, bio-inspired robots offer manoeuvrability, stealth and autonomy. They integrate propulsion and control systems into one multi-purpose undulatory propeller. By generating large counteracting forces, undulating fins generate a wide range of net torques and accelerations. Bio-inspired designs can provide stealth by imitating the motion patterns of organisms. Bio-inspiration provides strategies to integrate multimodal sensory information, and algorithms on how to form robot swarms. Multimodal sensing and swarming facilitate navigation during indeterminate tasks, such as surveying or maintenance, provide robot redundancy, and increase the temporal and spatial resolution of a mission. People have been inspired by... (read more)
2014-04-07 01:29:12

When Bathymetry Determines Who Might Live and Who Might Die

Bathymetry can Focus the Energy of Tsunamis, Storm Surges and Wind Waves
The importance of bathymetry may be obvious to mariners, ocean modellers and marine geologists, but among the general public only the boating community seems to understand the importance of knowing water depths and the shape of the sea bottom. Most uses of bathymetry are not compelling enough to attract the attention of the general public, yet there are many instances where knowing the shape of the bottom can save lives. Most dramatic are those times when the coast is struck by huge tsunamis, storm surges or wind waves. The direction and size of these long waves are affected by bathymetry... (read more)
2013-12-04 04:32:53

Global Navigation Satellite Systems

A Status Update
In this feature the current status and future development of four Global Navigation Satellite Systems (GNSS) are briefly presented. These four systems are the American Global Positioning System (GPS), the Russian Glonass, the European Galileo and the Chinese BeiDou Compass. All four systems offer, or will offer, civil navigation services (publicly open), as well as restricted access navigation services, which means for GPS, Glonass and most likely for Compass as well, military services. The European Galileo system will offer so-called Publicly Regulated Services (PRS) for use by the government. The basic principle of satellite navigation – referred to as standalone... (read more)
2011-03-16 12:04:30

‘Killer’ AUV Sonar System

In January 2001, C&C Technologies (C&C), a company based in Lafayette (Louisiana, USA), introduced the first commercially successful autonomous underwater vehicle (AUV) to the offshore industry. The AUV’s survey sensor suite, which included an EdgeTech side-scan sonar and sub-bottom profiler, performed well in the Gulf of Mexico and Brazilian offshore environments. However, West Africa proved more challenging – particularly for the sub-bottom profiler. C&C soon began searching for alternative technologies to provide better sub-bottom profiler penetration and higher resolution side-scan sonar imaging.Jim Chance, C&C Technologies (USA) Art Kleiner, EdgeTech (USA)<P> Narrator: Fast forward to the early autumn of 2004… C&C... (read more)
2008-04-02 12:00:00

Global Navigation Satellite Systems

Infrastructure Status and Developments
The concept of GNSS was first introduced by the European Space Agency (ESA), the European Commission (EC) and Eurocontrol in the early nineties. They defined requirements for a European GPS augmentation system, GNSS-1, and a full European satellite navigation system, GNSS-2, later together renamed EGNOS (European Geostationary Navigation Overlay System) and Galileo. Satellite navigation infrastructure status and developments are described here. Nowadays the term GNSS is used for the system of systems comprising GPS and GLONASS, with the later addition of Galileo. Satellite-based and ground-based augmentation systems (SBAS and GBAS) were introduced to augment GPS and GLONASS. Hydrographers were early... (read more)
2008-01-01 01:00:00
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