|MadSci Network: Earth Sciences|
The short answer is that there are tides in Hawaii, but they're smaller than in most other places. There are a couple reasons for this. The first is that there are points, usually near the centers of oceans, where the tides are much smaller. These points are called amphidromes. Hawaii is near the center of the Pacific Ocean, and is only a few hundred miles from one of these amphidromes.
Try this experiment to understand amphidromes: hold one end of a piece of rope, and have a friend hold the other end. Now start shaking your end up and down at a fairly slow rate. You should see waves moving along the rope, but there's a place in the middle of the rope that doesn't seem to move up and down. This is like an amphidrome.
The other reason tides are smaller in Hawaii is that there aren't large bays. On continents, large bays can sort of funnel the water so that tides are much larger than normal. Hawaii doesn't have any bays that are the right size and shape to do this.
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