Featured Research

from universities, journals, and other organizations

Predicting waves of large amplitude for tsunami warning systems

Date:
August 19, 2010
Source:
University of Vienna
Summary:
Navigators know that the shape of surface waves provides information about the strength of underlying water currents. This common seafarer’s knowledge is now the object of the scientific inquiry.

Navigators know that the shape of surface waves provides information about the strength of underlying water currents. This common seafarer's knowledge is the object of the scientific inquiry of Adrian Constantin Professor at the Faculty of Mathematics at the University of Vienna.

Funded by the Vienna Science and Technology Fund (WWTF), the project 'The flow beneath a surface water wave' aims to investigate the effect of currents on ocean waves. The results could be of importance for tsunami warning systems.

How can one distinguish mathematics from physics? While mathematics investigates properties of man-made abstract structures, physics seeks the general rules of nature by using mathematics. Adrian Constantin, who regards himself a 'pure mathematician', is entering unknown territory. The professor at the Faculty of Mathematics at the University of Vienna is investigating mathematical models for wave-current interaction. The aim of the four year project 'The flow beneath a surface water wave' is to study the effect of an underlying current on a surface water wave. 'Seaman claim that certain currents could double the amplitude of incoming waves. It is a big challenge to prove this assertion.'

When the sea retreats

The main reason for Constantin's study was the catastrophic tsunami in 2004 which resulted in more than 230,000 victims. Many aspects related to the disaster still remain vague. For example, prior to the arrival of the tsunami in Thailand the sea retreated, while in India there was no such warning. 'Satellite measurements show that in the direction of Thailand there was a first wave of depression, while in India the opposite direction was first confronted with a wave of elevation,' says Constantin.

Danger on beaches with a mild slope

The initial shape of the wave determines the behavior of tsunami waves as they approach the shore. A related question is the number of waves that hit a particular location. Mathematical considerations show that this number is related to the wave profile at its source. 'The number of tsunami waves close to the shore is never greater than the initial number of waves,' he explains. The amplitude of these waves can only be predicted roughly since this aspect is closely related to the often very complicated topography of the sea bed.

If we know the shape of the tsunami waves at an earlier point in time, we could predict some of its features as it approaches the shore. Constantin says, 'Tsunami waves are very dangerous at mildly sloped beaches, whereas in steep regions reflection occurs. The speed of the tsunami wave is proportional to the square root of the water depth.'

Pressure on the seabed

Constantin, an occasional diver, finds the pressure deep down in the sea to be of special interest. 'The pressure beneath provides information about incoming waves. As the wave crest approaches overhead one notices an increase of pressure, while a decrease in pressure signals the arrival of a wave trough'.

Data from the flume

In collaboration with the Franzius Institute of Hydraulics, Waterways and Coastal Engineering at the Leibniz University of Hannover Constantin is investigating whether the conclusions derived from mathematical models are in agreement with field data. 'The cooperation with the Ocean engineers is important to us. Because of their involvement in city planning for coastal regions in South East Asia threatened by tsunami events, they have access to a lot of tsunami specific data.' Moreover, the longest water wave tank in the world is located in Hannover and is being used by Constantin and his team for experiments.


Story Source:

The above story is based on materials provided by University of Vienna. Note: Materials may be edited for content and length.


Cite This Page:

University of Vienna. "Predicting waves of large amplitude for tsunami warning systems." ScienceDaily. ScienceDaily, 19 August 2010. <www.sciencedaily.com/releases/2010/08/100819083803.htm>.
University of Vienna. (2010, August 19). Predicting waves of large amplitude for tsunami warning systems. ScienceDaily. Retrieved April 18, 2014 from www.sciencedaily.com/releases/2010/08/100819083803.htm
University of Vienna. "Predicting waves of large amplitude for tsunami warning systems." ScienceDaily. www.sciencedaily.com/releases/2010/08/100819083803.htm (accessed April 18, 2014).

Share This



More Earth & Climate News

Friday, April 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Drought Concerns May Hurt Lake Tourism

Drought Concerns May Hurt Lake Tourism

AP (Apr. 18, 2014) Operators of recreational businesses on western reservoirs worry that ongoing drought concerns will keep boaters and other visitors from flocking to the popular summer attractions. (April 18) Video provided by AP
Powered by NewsLook.com
First Ever 'Female Penis' Discovered In Animal Kingdom

First Ever 'Female Penis' Discovered In Animal Kingdom

Newsy (Apr. 18, 2014) Not only are these newly discovered bugs' sex organs reversed, but they also mate for up to 70 hours. Video provided by Newsy
Powered by NewsLook.com
Ark. Man Finds 6-Carat Diamond At State Park

Ark. Man Finds 6-Carat Diamond At State Park

Newsy (Apr. 18, 2014) An Arkansas man has found a nearly 6.2-carat diamond, which he dubbed "The Limitless Diamond," at the Crater of Diamonds State Park. Video provided by Newsy
Powered by NewsLook.com
Deadly Avalanche Sweeps Slopes of Mount Everest

Deadly Avalanche Sweeps Slopes of Mount Everest

AP (Apr. 18, 2014) At least six Nepalese guides are dead after an avalanche swept the slopes of Mount Everest along a route used to climb the world's highest peak. (April 18) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins