Rogue or Freak Waves
Rogue or Freak (anomale) waves get their name
from their height, which is abnormally high compared to the sea heights observed
prior to the occurrence of this type of wave. The
USS Shreveport’s bow and crashed into the superstructure at bridge
level. It knocked out every window in the bridge,
and men and equipment were battered. Prior to meeting this freak wave, the seas
were normal, based on the wind conditions at the
time. Such abnormal waves are highly infrequent and totally unpredictable.
Oceanographers are not sure what causes these waves,
but based on studies of encounters such as that of the USS Shreveport,
oceanographers have found that these waves occur most
frequently in areas of strong sea-surface temperature gradients. Such gradients
exist where cold and warm sea currents meet. One such area
is the "North Wall" of the Gulf Stream, off
Cape Hatteras. Another area exists along the coast
of South Africa, where the cold Benguela
Current meets the warm Alguhas Stream.
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