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Home  Education  Tides and Water Levels  The Importance of Monitoring the Tides and Their Currents
  << Back Marine commerce is an  area in which tide and current predictions are critical. In June 2002,  these four marine cranes valued at $5 million cleared the Oakland  Bridge in San Francisco Bay by approximately 6 feet. If you look  carefully in the center of the image, you can see a shadowed figure  between the crane and the bridge. This is one of the mariners standing  on top of the crane and touching the bottom of the bridge as the barge  passes beneath it.


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