Sea Levels and the Coast

The oceans are a central part of the global climate system. As Roger Revelle, one of the early directors of the Scripps Institute of Oceanography, said, “The oceans exert a profound influence on mankind and indeed upon all forms of life on Earth. The oceans are inexhaustible sources of water and heat, and control the climate of many parts of the world.” He also recognised that “human beings are now carrying out a large-scale geophysical experiment of a kind that could have not have happened in the past nor be reproduced in the future”. Roger Revelle’s thoughts have even more... (read more)
2007-10-27 12:00:00

1997-2007: A Decade of Developments in Hydrography

We all know what is the oldest profession in the world. The second oldest is probably that of land surveyor: Adam undoubtedly wanted to stake out the boundaries of paradise in order to know what was and was not his. Paradise, or the Garden of Eden, was to be found in the land of the Euphrates and Tigris, where these two rivers converge at the town of Qurna in the present Shatt al Arab. And apart from his topographical activities Adam must also have made some hydrographic observations, probably just using a stick cut from a local fruit tree! After... (read more)
2007-02-02 12:00:00

Seabed Characterisation Using Wind Noise

The acoustic reflection coefficient of the seabed can be measured from the wind-generated noise of the ocean using a vertical line array of hydrophones suspended in mid-water. Results of experiments at several sites have previously been published and an example is presented here. The effect of the seabed on acoustic propagation from a source to receptor is illustrated by means of a simple formula.<P> The formula predicts thatfor a highly reflective seabed the received acoustic power at moderate ranges could be at least four times that received from a single direct path, and higher still at long ranges. Such effects... (read more)
2008-03-12 12:00:00

Following a Legacy

Hydro international Interviews Albert II, Prince of Monaco
At the invitation of Prince Albert I, the Principality of Monaco has been the headquarters of the International Hydrographic Organization since 1921. Looking at the annual reports of the International Hydrographic Bureau, the Government of the Principality has always been generous with the Organisation, providing it with beautiful premises and constant diplomatic support. Prince Albert II, Sovereign Prince of Monaco since April 2005, continues the tradition of his predecessors. Since 2001, Prince Albert is also president of the International Commission for the Scientific Exploration of the Mediterranean. He kindly accepted to be interviewed by Hydro international. You were named after... (read more)
2009-05-12 12:00:00

Acquiring and Integrating Bathymetric Lidar

Developing a Seamless Coastal DEM from Topographic and Bathymetric LiDAR Data
We investigated the most significant issues affecting the creation of a littoral zone digital elevation model from overlapping bathymetric and topographic Lidar (light detection and ranging) data. The main challenge was found to be the use of different methodologies used to establish vertical datums, as well as the narrow overlap between the two data sets, lack of ground control points and data gaps. We identified the main causes of gaps in bathymetric Lidar data and outline a new procedure for quantifying their occurrence. The Cooperative Research Centre for Spatial Information in Australia has been collaborating with the Victorian Department of... (read more)
2009-02-12 03:04:48

The Arctic Field Party

It seems ironic that in the early stages of the Cold War, the United States Government sent surveyors and hydrographic engineers to the coldest reaches of the North American continent. For these men, it was truly a Cold War. From 1945 through 1953, field parties of the United States Coast and Geodetic Survey were sent to survey sea routes through the Bering, Chukchi and Beaufort Seas as well as to conduct geodetic surveys to help position Distant Early Warning system radars and help delineate the vast resources of the Alaskan Arctic. These men toiled in obscurity beneath the midnight sun... (read more)
2017-07-04 11:00:42

Mariners Need More Current Hydrographic Data

Hydro International Interviews Rear Admiral Christian Andreasen, NOAA (Ret.)
Almost 50 years in hydrography gives you insight and authority to talk about the field and the changes it has gone through in half a century. Rear Admiral Christian Andreasen talks about his career. He is certainly not somebody who only looks back, but is still looking into the future, sharing strong ideas about where hydrography will need to go: ‘Mariners do not understand why hydrographic offices are not more supportive. Finding ways of providing mariners with more current data is an issue.’ Since the 1960s, when you became a hydrographer up to the present, the means and techniques for... (read more)
2012-06-06 03:35:09

Hydrography Will Be Big Contributor Filling the Digital Aquarium

Hydro International Interviews Mathias Jonas, Secretary-General of the International Hydrographic Organisation
The new secretary-general of the International Hydrographic Organisation (IHO), Mathias Jonas, has had a long career, now culminating in the highest rank within the world’s leading organisation for hydrography. He took office this autumn, succeeding Robert Ward, after he was elected in spring this year by the Member States. 'Hydro International' of course wants to know what Dr Jonas envisions for hydrography and the wider world it influences. Mathias Jonas starts off by sharing how he was already in touch with IMO and IHO in the nineties. ‘Arriving at the German maritime administration as a young professional mariner and as one... (read more)
2017-12-05 01:50:23

Waterside Mapping

Laser scanning and bathymetric side-scan sonar represent the cutting edge of environmental survey technology. Over the last few years, we have tested the integration of these two methodologies, carrying out a number of high-resolution surveys on the Po River, the Venice canals and various Italian harbours. Bathymetric surveys were conducted using a SEA SWATHplus-H wide-swath sonar. An Optech ILRIS-3D terrestrial laser scanner was used to scan the areas above water level. Information from these scans was used to create 3D black and white images (intensity images) of the surveyed area. In the case of the laser scanner, these images are... (read more)
2008-03-12 12:00:00

Surveying in the Ross Sea

The deepwater research vessel Tangaroa of the National Institute of Water & Atmospheric Research (NIWA) of New Zealand undertakes regular research expeditions to the Antarctic waters. In the last eight years, this 70m ice-strengthened vessel has successfully completed seven voyages to Antarctica: three of which were to the Ross Sea. This article describes her 48-day voyage in 2006. During this latest voyage, she once again collected data to extend our knowledge of the geophysical and biological make-up of the Ross Sea region Looking Back Tangaroa ’s first voyage to the Ross Sea was in February–March 2001, when it undertook a... (read more)
2007-05-09 12:00:00
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