Everything Totally Explained


Ask & we'll explain, totally!
Tidal bore
Totally Explained


  NEW! All the latest news in the worlds of computer gaming, entertainment, the environment,  
finance, health, politics, science, stocks & shares, technology and much, much, more.  


View this entry using RSS

Everything about Tidal Bore totally explained

A tidal bore (or just bore, or eagre) is a tidal phenomenon in which the leading edge of the incoming tide forms a wave (or waves) of water that travel up a river or narrow bay against the direction of the current. As such, it's a true tidal wave (not to be confused with a tsunami). Bores occur in relatively few locations worldwide, usually in areas with a large tidal range (typically more than 20 feet (6 m) between high and low water), and where incoming tides are funneled into a shallow, narrowing river via a broad bay. The funnel-like shape not only increases the height of the tide, but it can also decrease the duration of the flood tide down to a point where the flood appears as a sudden increase in the water level.
   Bores take on various forms, ranging from a single breaking wavefront — effectively a shock wave — to ‘undular bores’ comprising a smooth wavefront followed by a train of solitary waves (solitons). Larger bores can be particularly dangerous for shipping, but also present opportunities for river surfing.
   The word bore derives through Old English from the Old Norse word bára, meaning a wave or swell.
   Rivers that have been known to exhibit bores include those listed below.

Asia

South America

  • Amazon River in Brazil and Orinoco River in Venezuela, up to 4m (12 ft) high, running at up to 25 km/h (15 miles per hour). It is known locally as the pororoca.
  • Mearim River in Brazil.
  • Araguari River in Brazil.

    North America

  • Petitcodiac River in the Bay of Fundy, New Brunswick, Canada, formerly the highest bore in North America, over 2 metres (6 ft) high. It was reduced to little more than a ripple due to causeway construction and extensive siltation.
  • Shubenacadie River, also off the Bay of Fundy, Nova Scotia. When the tidal bore approaches, completely drained riverbeds are filled. The bore is fastest and tallest in some of the smaller rivers that connect to the Bay. It has claimed the lives of several tourists that were in the riverbeds when the bore came in.
  • Turnagain arm of Cook Inlet, Alaska. Up to 2 meters (6 ft) and 20 km per hour. Most rivers off the upper Bay of Fundy between Nova Scotia and New Brunswick have tidal bores. These include the River Hebert, Kennetcook River and Maccan River, the St. Croix River in the Minas Basin, and the Salmon River in Truro.

    Europe

    United Kingdom

  • River Dee, Wales / England
  • River Mersey
  • River Severn, Wales / England up to 2 meters (7 ft) high
  • River Trent, (the Aegir) up to 1.5 meters (5 ft) high, England and other tributaries of the Humber Estuary
  • River Parrett
  • River Welland
  • River Kent
  • River Great Ouse
  • River Ouse, Yorkshire
  • River Eden
  • River Esk
  • River Nith

    France

    The phenomenom is generally named un mascaret in French but some other local names are preferred.
  • Seine, locally named la barre, had a significant bore until the 1960s. Since then it has been practically eliminated by dredging.
  • Couesnon
  • Sélune
  • Vilaine, locally named le mascarin
  • Dordogne River
  • Garonne River

    Norway

  • Saltstraumen near Bodø, claimed to be the strongest tidal current in the world.

    Australia

  • Styx River, Queensland, Australia
  • Daly River, Northern Territory, AustraliaFurther Information

    Get more info on 'Tidal Bore'.


    External Link Exchanges

    Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:

      <a href="http://tidal_bore.totallyexplained.com">Tidal bore Totally Explained</a>

    Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
       As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned.



  • Copyright © 2007-8 totallyexplained.com | Licensed under the GNU Free Documentation License | Site Map
    This article contains text from the Wikipedia article Tidal bore (History) and is released under the GFDL | RSS Version