A-frame

Aaberg, Denny

Aaberg, Kemp

Abberton, Koby

Abbruzzi, Sid

Abellira, Reno

Abubo, Megan

academia and surfing

Adler, Tom

advertising and surfing

Aeder, Erik

aerial

Aguerre, Fernando

Aichner, Scott

Aikau, Clyde

Aikau, Eddie

Aipa, Ben

air-drop

airbrush

Airshow

Ala Moana

Alabama

alaia board

Alaska

alcohol and surfing

Alexander, Kala

Allen, Chuck

Alms, Paige

aloha shirt

Alter, Hobie

Alvarez, Pepe

Ancell, Kevin

Andaman Islands

Andersen, Lisa

Anderson, Craig

Anderson, Simon

Andino, Kolohe

Angel, Jose

angle

Angola

Angourie

Antarctica

Apocalypse Now

Arabian Sea

Aragon, Janice

Arakawa, Eric

Archbold, Matt

Arena, Eduardo

Ashton, Juan

Association of Surfing Professionals (ASP)

Atlantic Ocean

August, Robert

Aurness, Rolf

Auster, Ken

Australia

Avalon, Frankie

Azores

backdoor

backside

backside attack, Pipeline

backwash

bail out

Bain, Rob

Baja California

Baker, Bernie

Baker, Grant “Twiggy”

Baker, Tim

Bali

Ball, John “Doc”

Ballard, Bill

Ballard, Rochelle

balsa

Baltic Sea

Banks, Jim

Barbados

Barilotti, Steve

Barland, Michel

Barreda, Sergio “Gordo”

Barry, Michael

Bartholomew, Wayne

Baxter, Jackie

Bay of Bengal

Beach Boys, The

Beacham, Debbie

beachboys

beachbreak

Beachcomber Bills Grand Prix

Beachley, Layne

beavertail

Becker, Phil

Bedford-Brown, Stuart

Belgium

Bells Beach

Bendall, Ma and Pa

Bennett, Barry

Benson, Becky

Benson, Blanche

Benson, Linda

Bermuda

Bertlemann, Larry

Tidal bore waves are formed in a small number of ocean-connected rivers worldwide, and take shape when a higher-than-average tide funnels through a rivermouth into a narrowing inland passage. The best-known surfing tidal bores are found in Britain's Severn River, the Amazon in Brazil, and the Dordogne River in France. Equinox tides generally produce the biggest bore surges, and a breaking bore wave will travel at two or three times the speed of the incoming tide. (The Severn wave moves at six to eight miles per hour; a 10-foot ocean wave generally travels at about 12 miles per hour when it breaks.) Bore waves are almost always larger near the riverbanks than at midstream, and the outer bank in a curve tends to produce an even bigger wave— occasionally up to eight foot or more. English surfer Rodney Sumpter introduced tidal bore surfing to the public with his 1968 Surfer magazine article "The World's Most Unusual Wave." Rides on the French Dordogne, through the scenic heart of Bordeaux wine country, last up to 10 minutes—short surfboards are occasionally used, but local river surfers prefer longboards, canoes, or surf-skis—and finish 60 miles from the nearest beach. The Pororoca, an Amazon River bore in northern Brazil was first surfed in 1997, has been featured in Surfer and the Surfer's Journal, and was the subject of a National Public Radio feature story. Bore waves are also found on the Shubenacadie River in Nova Scotia, the Turnagain in Alaska, the Hugli in India's West Bengal, and the Batang Lupar in Malaysia's Sarawak state. The largest recorded tidal bore wave swept up China's Qiangtaing River in 1993; it rose up to 20 feet in places, traveled 200 miles, and killed more than 100 people. See also Pororoca, Severn Bore.

tidal bore waves

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Encyclopedia of Surfing

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Encyclopedia of Surfing

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