Exactly what are the ocean's tides?

August 14, 2015, 11:55 a.m.

When we talk about tides, most of us think it's just when the ocean is higher on the beach or lower on the beach. But there's more to the tide than this. High tide is actually the crest of a really long wave.

NOAA explains, "Tides are very long-period waves that move through the oceans in response to the forces exerted by the moon and sun. Tides originate in the oceans and progress toward the coastlines where they appear as the regular rise and fall of the sea surface. When the highest part, or crest, of the wave reaches a particular location, high tide occurs; low tide corresponds to the lowest part of the wave, or its trough. The difference in height between the high tide and the low tide is called the tidal range."

Everyone knows that the moon's gravitational pull causes the tides. But the sun's gravitational pull also plays a role. The sun's gravitational force is only about 46 percent of the moon's, which means its pull on Earth's oceans is smaller and so too is its effect on the tides. Thus, when the moon, the sun, and Earth are aligned, the pull of the sun adds to the pull of the moon and causes extreme tides. Or, extra long waves.

And one last little fun fact, the highest tides in the world are found at the Bay of Fundy in Nova Scotia, where they have a range of 44.6 feet!

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Jaymi Heimbuch is a writer and photographer at Mother Nature Network. Follow her on Twitter, Google+ and Facebook.