Rabinovich, A B; Stephenson, F E

Natural Hazards. Vol. 32, no. 3, pp. 313-343. July 2004

A few years ago the Canadian Hydrographic Service initiated a major upgrade to all tide gauges and tsunami stations on the coast of British Columbia (B.C.). This program was undertaken to address shortcomings of the earlier digital systems and was driven by concerns about emergency response continuity in the year 2000. By 1999, thirteen tide gauge stations had been installed and were operational. Three of these stations (Tofino, Winter Harbour, and Langara) were selected for use as tsunami warning stations. Several years of continuous, high quality data have now been collected at these stations and used for analysis of long waves in the tsunami frequency band. Careful examination of these data revealed two weak tsunamis recorded by several B.C. stations: a distant tsunami of June 23, 2001 generated by the Peru Earthquake (Mw = 8.4), and a local tsunami of October 12, 2001 induced by the Queen Charlotte Earthquake (Mw = 6.3). Spectral characteristics of these two tsunamis are compared with the spectral characteristics of long waves generated by a strong storm (October, 2000) and of ordinary background oscillations. The topographic admittance functions (frequency responses) constructed for all stations showed that most of them (in particular, Winter Harbour, Tofino, Bamfield, Port Hardy, and Victoria) have strong resonance at periods from 2.5 to 20 min, indicating that these locations are vulnerable to relatively high-frequency tsunamis. The Winter Harbour station also has two strong resonant peaks with periods of 30 and 47 min and with amplification factors of about 7. The estimated source functions show very clear differences between long waves associated with the seismic source (typical periods 10-30 min) and those generated by a storm, which typically have shorter periods and strong energy pumping from high-frequencies due to non-linear interaction of wind waves.

van Genderen, J L; van Zuidam, R A; Fager, S G

the 1st Thematic Conference on Remote Sensing for Marine and Coastal Environments; New Orleans, LA; USA; 15-17 June 1992. pp. 647-656. 1992

A major objective of the study is to define an operational environmental information system (EIS) for integrated coastal zone management (ICZM) in developing countries. The approach includes the development of an implementable method (in terms of data requirements, parameters involved in ICZM which are able to be recognized and measured by remote sensing and an analysis of the platforms, sensors, spatial, spectral and temporal resolution requirements) that will allow policy makers, planners and decision makers to focus on major ICZM issues in developing countries, and to permit the definition of an effective programme including investment, policy and institutional measures. The study has identified a major need in terms of training and education in the role of remote sensing and GIS for integrated CZM in developing countries. The coastal ecosystems which can be studied by remote sensing and entered into an EIS include amongst others deltas, estuaries, marshes, mangroves, seagrass beds, coral reefs and lagoons, beaches, small islands, sandy and muddy bottoms and rocky coasts. Man-made features which also can be monitored include ports, commercial fisheries and aquacultural operations, industries, recreational and tourist developments, archaeological sites and, especially in the developing countries, some of the largest and most densely populated urban areas in the world. Many developing nations face different problems in ICZM to those in developed Western nations, many of which can only be solved by using remote sensing and GIS tools. Coastal hazards such as earthquakes, tsunamis, tropical storms, floods and volcanic eruptions are but one example of the unique problems facing many developing countries. The paper concludes with some recommendations for establishing EIS for ICZM in developing countries and provides guidelines for further research needs.

Nowak, R

New Scientist. Vol. 185, no. 2482, pp. 16-17. 15 Jan. 2005

Researchers such as those at the Pacific Marine Environmental Laboratory, Seattle, are among the small community of tsunami experts who, three weeks after the tsunami which struck the coasts surrounding the Indian Ocean on 26th December 2004 are just beginning to understand the nature of waves that wreaked such destruction over a wide area. It used to take years to model a tsunami but now it can be done in almost real time, but not without crucial data missing from the Indian Ocean tsunami. So far the best evidence suggests that a large are of the sea floor lifted by up to 5 metres, while other parts dropped by 2.5 metres. The body of water above, five kilometres high, instantly moved with it, and this caused the tsunami to form. (Quotes from original text)

Trabant, P; Watts, P; Lettieri, F; Jamieson, G

Offshore. Vol. 61, no. 5, pp. 118, 120. May 2001

Rivers responding to global warming at the end of the last ice age carried sediments across the present shelf, when the sea level was 100 metres lower than at present. Rapid accumulations of sediments at the shelf edge can lead to mass slope failure, assisted by gravity. Submarine slumps occurring in this manner can produce a tsunami. Recent modelling of the East Breaks slump in the Gulf of Mexico, which occurred between 10,000-20,000 years ago, has concluded that the resulting tsunami would have had a wave height in the order of 7.6 metres, would have travelled across the continental shelf and flooded the Texas coastline. Today, the occurrence of a slope failure at the present shelf edge could present a hazard to deepwater hydrocarbon production facilities, and the resulting tsunami could devastate coastal communities. This article argues there are sufficient details to warrant an in-depth study of shelf edge mass movements to assess their occurrence and potential impact. (Abstract quotes from original text)

Walker, G

New Scientist. Vol. 168, no. 2269, pp. 40-3. 16 Dec. 2000

For the past four years, American geologist Richard Schweickert has been painstakingly mapping the many geological faults in and around Lake Tahoe, on the border between California and Nevada, and his findings have led him to a startling conclusion. The combination of seismic activity and lake water means only one thing. It doesn't matter that we're more than 400 kilometres from the open ocean: Schweickert and his colleagues are convinced this is a prime spot for tsunamis. (Quotes from original text)

Marshall, T

New Scientist. Vol. 167, no. 2259, pp. 26-30. 7 Oct. 2000

Simon Day of University College London has discovered that a huge chunk of La Palma, the most volcanically active island in the Canaries, is now unstable. If the volcano slides into the ocean, it could create a tsunami wave far larger than anything seen in history. With a height of 40 or 50 metres, the tsunami would be heading straight for the US, engulfing everything in its path for up to 20 kilometres inland.

Dorminey, B

Financial Times , pp. 11. 16 Dec. 1997

Describes progress being made in setting up deep-sea observatories. Permanent sea-floor observatories only exist at the moment in shallow coastal waters, but various projects are under way to study ocean dynamics at far greater depths. One project awaiting funding is the deep-sea observation system planned for two sites at a depth of 1.5km, covering an area of 20km per site, along the Juan de Fuca Ridge off the US west coast. Evolving technology would be expected to enable the observatory to function for up to 30 years. Another project, the Hawaii-2 observatory, lies at a depth of 5.5km, halfway between California and Hawaii. It begins operation in September 1998 to maximize coverage for the Iris Global Seismographic Network and provide information for studies on tsunamis. An adjacent article describes the work of Jason, an undersea robot: this remotely operated vehicle (ROV) has been used to retrieve items from several shipwreck sites, using an extremely accurate navigation system.

Kanamori, H; Heaton, T H

Nature. Vol. 379, no. 6562, pp. 203-4. 18 Jan. 1996

Although quiet this century, the `Cascadia subduction zone', a region on and offshore western North America from northern California to southern British Columbia, has produced big earthquakes in the past. A new study involving Japanese documents written 300 years ago shows that a tsunami (seismic sea wave) which reached Japan on the night of 27/28 January 1700 probably originated as a result of an earthquake in Cascadia of giant magnitude (M>9). These findings reinforce the need to be prepared for future giant earthquakes and resultant tsunamis originating in this area.

Hyndman, R D

Scientific American. Vol. 273, no. 6, pp. 50-7. Dec. 1995

New studies of geological records indicate the possibility of an earthquake in the so-called `Cascadia subduction zone', a region on and offshore from northern California to southern British Columbia. The last large earthquake about 300 years ago created tsunamis (seismic sea waves) which reached Japan. Before that, similar events occurred at irregular intervals of about 500 years.

Swinbanks, D

Nature. Vol. 371, no. 6498, pp. 549. 13 Oct. 1994

A major earthquake (7.9 on the Richter scale) offshore from the northern tip of Japan on 4 October 1994 exposed both the strengths and weaknesses of Japan's disaster prevention measures in the aftermath of such events. Tsunami warnings were broadcast on television very quickly, and some accurate predictions were made, but information on the earthquake itself was slower and some of it inaccurate and misleading. The Japan Meteorological Agency (JMA) has added 150 unmannned meteorological stations to measure earthquake effects, and will issue the highest readings within 2 minutes of an earthquake occurrence.

Okal, E A

Nature. Vol. 361, no. 6414, pp. 686-7. 25 Feb. 1993

Smith, D; Dawson, A

New Scientist. Vol. 127, pp. 46-9. 4 Aug. 1990

Thatcher, W

Nature. Vol. 340, pp. 674-5. 31 Aug. 1989

Carrier, G F; Noiseux, C F

Journal of Fluid Mechanics. Vol. 133, pp. 147-60. Aug. 1983

King, D R; LeBlond, P H

Journal of Fluid Mechanics. Vol. 117, pp. 269-82. Apr. 1982

Miles, J W

Journal of Fluid Mechanics. Vol. 109, pp. 115-123. 1981

The gravity-wave scattering matrix for a barrier reef that separates two different depths of water is calculated by an extension of a variational analysis of diffraction by a discontinuity in depth. The results are applied to the calculation of resonant amplification of incoming swell or tsunamis by a shallow lagoon that is bounded by the reef and a vertical inner boundary.

Hogan, J; Young, E

New Scientist. Vol. 185, no. 2482, pp. 12-13. 15 Jan. 2005

In the aftermath of the tsunami which struck the coasts surrounding the Indian Ocean on 26th December 2004, considerable attention is being paid to how the communities are going to rebuild their towns and villages and how they may prepare for future tsunamis, using the massive amounts of aid cash to put in place the sort of warning system that might otherwise be prohibitively expensive. Attention is also being focused on ways of making buildings more tsunami-resistant, including ground floor walls which can break way from supports.

Coco, D

Computer Graphics World. Vol. 21, no. 8, pp. 72, 74. Aug. 1998

Describes the tough challenges faced by Industrial Light and Magic when creating the 1000-foot tidal wave sequences, caused by a comet hitting the Earth, in a film called 'Deep Impact'. Realistic creation of the ensuring surf that washed over land, buildings, and people, was equally challenging as ILM didn't have any clips to work from.

Johnstone, B

New Scientist. Vol. 154, no. 2087, pp. 36-9. 21 June 1997

The Bronze Age Minoan civilization of Crete was destroyed some 3500 years ago. Volcanologists believe that the volcano Santorini was responsible, not so much because of its hot ash but because it caused a giant tidal wave (tsunami). Joe Monaghan, an applied mathematician, has developed a modelling technique called smoothed particle hydrodynamics (SPH) which can test this theory by creating tsunamis in the laboratory.

Walker, G

New Scientist. Vol. 148, no. 2005, pp. 32-5. 25 Nov. 1995

A tsunami is a series of mountainous waves generated when a section of the sea bed lurches upwards during an earthquake lifting a vast body of water with it, and is particularly prone to occur in the Pacific.