Help! Marine Biology....??

Question

i have a presentation tmw about seiches,tsunamis, seismic waves, storm surges.... Any information would help tremendoulsy.. thanks!!!!

Answer 1

A seiche is a standing wave in an enclosed or partially enclosed body of water. Seiches and seiche-related phenomena have been observed on lakes, reservoirs, bays and seas. The key requirement for formation of a seiche is that the body of water be at least partially bounded, allowing natural phenomena to form a standing wave.

The term was first promoted by the Swiss hydrologist François-Alphonse Forel in 1890, who had observed the effect in Lake Geneva, Switzerland. The word originates in a Swiss French dialect word that means "to sway back and forth", which had apparently long been used in the region to describe oscillations in alpine lakes.

A tsunami (pronounced tsoo-nah-mee; IPA: /tsʊˈnɑːmi/) is a series of waves created when a body of water, such as an ocean, is rapidly displaced on a massive scale. Earthquakes, mass movements above or below water, volcanic eruptions and other underwater explosions, landslides, large meteorite impacts and testing with nuclear weapons at sea all have the potential to generate a tsunami. The effects of a tsunami can range from unnoticeable to devastating. The term tsunami comes from the Japanese words(津波、つなみ) meaning harbor ("tsu", 津) and wave ("nami", 波). Although in Japanese tsunami is used for both the singular and plural, in English tsunamis is often used as the plural. The term was created by fishermen who returned to port to find the area surrounding their harbor devastated, although they had not been aware of any wave in the open water. Tsunami are common throughout Japanese history; approximately 195 events in Japan have been recorded.

A tsunami has a much smaller amplitude (wave height) offshore, and a very long wavelength (often hundreds of kilometers long), which is why they generally pass unnoticed at sea, forming only a passing "hump" in the ocean. Tsunami have been historically referred to as tidal waves because as they approach land, they take on the characteristics of a violent onrushing tide rather than the sort of cresting waves that are formed by wind action upon the ocean (with which people are more familiar). Since they are not actually related to tides the term is considered misleading and its usage is discouraged by oceanographers. [1] Since not all tsunami occur in harbors, however, that term is equally misleading, although it does have the benefit of being misleading in a different language.

A seismic wave is a wave that travels through the Earth, most often as the result of a tectonic earthquake, sometimes from an explosion. Seismic waves are also continually excited by the pounding of ocean waves and the wind. Seismic waves are studied by seismologists, and measured by a seismograph, which records the output of a seismometer, or geophone. For seismic studies of oil reservoirs, hydrophones may give additional information.

A storm surge is an onshore gush of water associated with a low pressure weather system, typically a tropical cyclone. Storm surge is caused primarily by high winds pushing on the ocean's surface. The wind causes the water to pile up higher than the ordinary sea level. Low pressure at the center of a weather system also has a small secondary effect, as can the bathymetry of the body of water. It is this combined effect of low pressure and persistent wind over a shallow water body which is the most common cause of storm surge flooding problems.

Storm surges are particularly damaging when they occur at the time of a high tide, combining the effects of the surge and the tide. This increases the difficulty of predicting the magnitude of a storm surge since it requires weather forecasts to be accurate to within a few hours.

The most extreme storm surge events occur as a result of extreme weather systems, such as tropical cyclones, but storm surges can also be produced by less powerful storms.

The highest storm surge ever recorded was produced by the 1899 Cyclone Mahina, which caused a 13 meters (43 feet) storm surge at Bathurst Bay, Australia[citation needed]. In the United States, the greatest recorded storm surge was generated by 2005's Hurricane Katrina, which produced a storm surge 9 meters (30 feet) high in the town of Bay St. Louis, Mississippi[citation needed], and in the surrounding coastal counties. The worst storm surge, in terms of loss of life, was the 1970 Bhola cyclone and in general the Bay of Bengal is particularly prone to tidal surges.

All this info is from www.wikipedia.com

It has a lot more info if this doesn't cover what you need.

Oh, and this would be considered marine geography.