Ocean waves are also described in terms of wave period. On the ocean, it may be easier and more accurate to record how long it takes ten waves to pass and then divide by ten to obtain the average period. An ocean wave is also characterized by wave speed, or the distance it travels divided by the time it takes to travel that distance. Record the wave speed and circle the generating factor in the table. Tides can be thought of as global-scale ocean waves generated by gravitational attraction of the Moon and Sun.
High tide is the crest of the wave and low tide the trough.
Where two high tides occur each day, the wave period is about 12.5 hours. Tsunamis, sometimes erroneously called tidal waves, are ocean waves generated by earthquakes and submarine landslides. They have a period of about 0.5 hour and a wavelength of about 200 km. Again, determine the wave speed as above and record all three characteristics and circle the generating factor in the table.