Hobbies And Interests
Wind
Wind is the most common cause of waves. Breezes and strong wind gusts blow across the ocean and create friction on the ocean's surface. The friction forces the water to ripple, and the the ripples can grow into large waves if the wind is strong enough and blows for a long distance and time. Storms can generate winds that cause waves that last several days. These storms cause waves that can be damaging to coastlines. Some geographic areas get consistently high wind levels, making them destinations for surfers.
Earthquakes
Earthquakes can cause devastating waves called tsunamis by generating a large amount of energy that moves a large volume of water toward a coast. Out in the ocean, the tsunami may appear to be just a few inches tall, but as it hits shallower water the tsunami can crash upward onto land violently and destructively. In 2011, a tsunami in the Pacific Ocean killed more than 15,000 people and destroyed or damaged more than 125,000 buildings in Japan. Tsunamis can also be caused by volcanic activity and landslides.
Man-made Causes
Small waves can be caused by ship wakes, construction near a coast or any other human activity in the water. These waves are often minuscule compared to ocean waves caused by natural forces. Man-made waves rarely last long because of the small amount of energy over a short period of time that caused them. Humans can cause larger disturbances in the ocean, though. Larger waves and even destructive tsunamis can be caused by man-made underwater explosions.
Surf
Nondestructive waves become a surf once they approach the coast. In the deep ocean, a wave caused by wind or a passing ship does not touch the ocean floor and appears to be a small ripple. Once the waves can touch the ocean floor, they become taller and taller until they break or curve on top of themselves. This is known as a surf, and experienced surfers can identify safe surfing waves by watching the surf roll in toward the shore.