Low-budget Hydrography

Opinions from differing backgrounds
Low-budget Hydrography is the theme of this issue. Realising that different players in hydrography will have differing opinions on various aspects of low-budget hydrography and interested in exploring these divergent views on your behalf, HI asked representatives from various camps for their opinions on some leading questions. The representatives interviewed are: Jeffrey F. Marlow, Survey Technician, US Army Corps of Engineers CDR Guy Noll, Commanding Officer, NOAA Ship RAINIER LTCDR Richard Cullen, Staff Officer Quality Control AHS Questions: 1. Can you briefly explain your position in the hydrographic world: your experience and present position? Cullen: I have been employed by... (read more)
2008-01-01 01:00:00

'As it Was'

by the Old Hydrographer
Matthew Fontaine Maury is probably the best known of all hydrographers, and the most celebrated both in his homeland, the United States of America, and in Europe. He served for 18 years as Superintendent of the Depot of Charts and Instruments in Washington during which time he made his name with the publication of his Wind and Weather Charts and Sailing Directions, his bathymetric chart of the North Atlantic and his book 'The Physical Geography of the Sea'. Two Huguenot families, who had fled from France after the Revocation of the Edict of Nantes in 1685, had come together in... (read more)
2008-01-01 01:00:00

New Bathymetric Data Assessment at the UK Hydrographic Office

To support the production and maintenance of navigational charts, the United Kingdom Hydrographic Office (UKHO) receives large quantities of bathymetric data from a great number of sources. This data is all assessed for possible dangers to navigation and, where such dangers exist, promulgated by the Notices to Mariners system. Because of the safety implications, time is of the essence and UKHO uses an in-house developed system to reformat, store and assess the data. Although the system is now getting somewhat dated, has limited functionality and is due for replacement, it has stood the test of time and the principles of... (read more)
2008-01-01 01:00:00

Furthering Ocean Science Using Innovative Marine Robotics

First Results of Unmanned Surface Vehicle Trials Revealed
Robotics and autonomous systems are championed as one of the UK government’s ‘Eight Great Technologies’. The National Oceanography Centre is committed to maximising this technology to further ocean science and has purchased a fleet of innovative autonomous surface vehicles, each with different specifications and capabilities. The fleet – including custom-designed vessels — was put through its paces late last year in an ambitious project. The first results from this mission have been revealing, with each vehicle proving it has a part to play in the future of autonomous research. When it comes to ocean exploration and discovery, the potential of... (read more)
2015-08-06 02:51:24

ECDIS – Caveat Navigator

Is the Paperless Bridge a Hazard to Navigation?
Hydrographic data is at the core of ECDIS. The International Hydrographic Organization (IHO) is of the opinion that the quantity and coverage of good hydrographic data around the world is mostly unsatisfactory. Meanwhile, the overall hydrographic data acquisition capacity of its member States is declining. Is there a proper appreciation of the quality and reliability of the data behind the image displayed on the screen? Does the digital presentation of nautical charts give a false sense of security? The paper chart or Raster Navigational Chart (RNC) displays all safety critical navigational information at once. The Electronic Navigational Chart (ENC) is... (read more)
2012-07-26 02:51:48

General Description of XML File CUBE Parameters

To Process Data from a Survey with CARIS HIPS
Interferometric sonars acquire millions of soundings in a hydrographic survey. The processing of this data by a hydrographer without a reliable statistical algorithm like CUBE (Combined Uncertainty and Bathymetry Estimator), to obtain a bathymetric map, would be practically impossible. CARIS HIPS software allows the use of the CUBE algorithm, invented by Dr Brian Calder, with an editable XML file to process the millions of soundings acquired in a survey. A good adjustment in the values ​​of these parameters improves the outcome of the CUBE model, obtaining a seafloor as close to reality as possible. The values ​​of these parameters mainly... (read more)
2017-07-19 10:22:29

Coastal Mapping Around Shore Parallel Breakwaters

Using a Standard Marine X-band Radar
Surveying very shallow coastal areas can be a logistically difficult and time-consuming process. Mapping the embayments around a series of shore parallel breakwaters at Sea Palling on the south-east coast of England has proven an interesting challenge for a new radar-based remote mapping technique. This technique uses the wave behaviour visible as sea clutter on a marine radar to infer the underlying water depth that caused the observed wave behaviour, allowing large areas of the seabed to be mapped without having to deploy boats or people. View Larger Map   When new breakwaters at Sea Palling proved more effective than... (read more)
2009-02-12 04:08:28

Depth of Cable Cover Gets New Look

New Technology Reduces Cost
Burying utility cables under the seabed in shallow water environments to ensure cable safety is accelerating because of green power generation initiatives and the relative ease of securing permits to lay cable in rivers or estuaries compared to onshore right-of-ways. In locations with shifting sands and bottom profiles, verification that the utility line remains covered is often required. A new remote sensing method has been developed to accomplish depth-of-cover utility surveys at greatly reduced cost. Maintaining underwater utility infrastructure varies with water depth. ROVs are generally used in deep water. In less than 50 metres, such as nearshore, estuaries, bays,... (read more)
2011-07-15 04:13:41

3D Sonar Technology

The journey from oil and gas to homeland security and back again
Since its introduction many years ago, survey sonar has evolved steadily, but is still a difficult and non-intuitive survey tool, requiring large amounts of processing to arrive at the most basic end product. Initially, anyone wanting to survey or inspect the underwater environment was limited to single beam echo-sounders, in simple terms one-dimensional sonar, yielding very little quantifiable data. These in turn were developed into mechanically scanned sonars, and subsequently into today’s high performance multi-beam and forward looking sonars which are the back-bone of the survey industry. Even the very best commercially available multi-beam sonar delivers only 2 dimensional data... (read more)
2008-01-01 01:00:00

A Universal Hydrographic Database

In search of ‘The Holy Grail’
The idea of a Universal Hydrographic Database is well known within the hydrographic community. Years of discussion and technological development have made UHD an attractive goal for those striving to improve the quality of navigation products. As seekers of this ‘Holy Grail’, the authors dare to suggest requirements for such a database and even analyse approaches to implementation. The main task for a HO is, as stated in regulation 9 of SOLAS Chapter V, to provide for safe navigation within its zone of responsibility. All other tasks are just incremental steps toward fulfilling this main objective. They include survey, production... (read more)
2008-01-01 01:00:00
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