Section outline

  • Surfin' U.S.A.
    ::美利坚

    Jaws  Beach  in Maui, Hawaii has legendary waves. The largest waves come when  winds  are very strong, usually in the winter. The   and  reef  offshore magnify the size of the incoming wave  energy . Cowabunga!
    ::夏威夷毛伊岛的乔斯海滩有传奇的波浪。最大波浪是当风势很大时,通常在冬季。海滨和珊瑚礁放大了即将到来的波浪的能量。科瓦邦加!

    Waves
    ::波浪

    Most ocean waves are caused by winds. A  wave  is the transfer of energy through matter. A wave that travels across miles of ocean is traveling energy, not  water . Ocean waves transfer energy from wind to the water. The energy is transferred from one water  molecule  to the next. The energy of a wave may travel for thousands of miles. The water itself moves very little. The picture below shows how water molecules move when a wave goes by ( Figure   ). Once the wave starts, it doesn't need more wind to keep it going.
    ::大多数海洋波都是由风造成的。波浪是能量通过物质转移。波浪横跨海洋数英里的波浪是流动能量,而不是水。海浪将能量从风向水转移。能量从一个水分子转移到下一个水中。波的能量可能移动数千英里。水本身移动得很少。下面的图示显示当波浪经过时水分子是如何移动的(图 ) 。一旦波浪开始,就不需要更多的风来维持它。

    Wave properties and water molecule movement in ocean waves.

     

    A wave travels through the water. How would you describe the movement of water molecules as a wave passes through?
    ::一波穿过水面,你会如何描述水分子的移动?

    The Size of Waves
    ::波浪的大小

    The figure above also shows how the size of waves is measured ( Figure   ). The highest point of a wave is the  crest . The lowest point is the  trough . The vertical distance between a crest and a trough is the  wave height . Wave height is also called  amplitude . The horizontal distance between two crests is the  wavelength . Both amplitude and wavelength are measures of wave size.
    ::上图还显示了如何测量波的大小(图)。波的最高点是峰值。最低点是底线。顶点和底线之间的垂直距离是波高。波高也称为振幅。两个顶点之间的水平距离是波长。振幅和波长都是波大小的量度。

    The size of an ocean wave depends on how fast, over how great a distance, and how long the wind blows. The greater each of these factors is, the bigger a wave will be. Some of the biggest waves occur with  . A hurricane is a  storm  that forms over the ocean. Its winds may blow more than 150 miles per hour! The winds also travel over long distances and may last for many days.
    ::海洋波的大小取决于速度、距离和风吹的长度。 这些因素越大, 海浪就越大。 一些最大的海浪会随之而来 。 飓风是海洋上形成的风暴, 风每小时可能吹150英里以上 。 风也会长途飘移, 可能持续许多天 。

    Breaking Waves
    ::断波波

    The figure below shows what happens to waves near shore ( Figure   ). As waves move into shallow water, they start to touch the bottom. The base of the waves drag and slow. Soon the waves slow down and pile up. They get steeper and unstable as the top moves faster than the base. When they reach the shore, the waves topple over and break.
    ::下图显示了海岸附近的海浪(图 ) 。 当海浪向浅水移动时, 它们开始触摸海底。 海浪的底部会拖慢。 很快, 海浪会减慢并堆积起来。 当海浪的顶部移动比底部更快时, 海浪会更陡峭和不稳定。 当海浪到达岸边时, 海浪会翻转而破裂。

    Wave behavior as they approach shallow water and break onshore.

     

    Waves break when they reach the shore.
    ::海浪到达岸边时断裂

    Storm Surge
    ::风暴暴雨暴雨

    Some of the damage done by storms is from  storm surge . Low pressure in a storm pulls water upward. Water piles up at a shoreline as storm winds push waves into the coast. Storm surge may raise  sea level  as much as 7.5 m (25 ft). This can be devastating in a shallow land area when winds, waves, and  rain  are intense.
    ::风暴造成的一些破坏来自风暴潮。风暴中的低压将水引向上方。当风暴向海岸倾斜时,河水会堆积在海岸线上。 风暴潮可能会使海平面升高7.5米(25英尺 ) 。 当风、波浪和雨量密集时,这可能会对浅陆地地区造成毁灭性影响。

    Maverick waves are massive. Learning how they are generated can tell scientists a great deal about how the ocean creates waves and especially large waves.
    ::马华力海浪是巨大的。 学会如何产生这些海浪可以告诉科学家很多关于海洋是如何产生海浪,特别是大浪的。

    Summary
    ::摘要

    • The largest wind waves are built when a strong wind blows for a long time over a large area.
      ::最大的风浪是在大片地区长时间强风吹过时形成的。
    • It is not the water that travels in a wave; it is the energy that is transferred from where the wave formed.
      ::并不是水在波浪中流动;而是能量从波浪形成的地方转移而来。
    • A wave breaks when it is too tall to be supported by its base. This is common as a wave moves up the shore.
      ::当波浪太高而不能得到其基地的支持时,波浪会断裂。 当波浪向岸上移动时,波浪会很常见。

    Review
    ::回顾

    1. How does a wave break onshore? How does a wave break in the ocean?
      ::海浪如何冲上岸?海浪如何冲进海洋?
    1. How does a wave move across the ocean?
      ::海浪如何横跨海洋?
    1. How do hurricanes create large waves?
      ::飓风如何制造大浪?

    Explore More
    ::探索更多

    Use the resources below to answer the questions that follow.
    ::利用以下资源回答以下问题。

    1. What can cause waves?
      ::什么能引起波浪?
    1. Where does the energy in a wave come from and how does it get into the wave?
      ::海浪中的能量从何而来 如何进入海浪?
    1. What three factors affect the size and strength of waves?
      ::哪些三个因素影响海浪的大小和强度?
    1. How are large waves created?
      ::大浪是如何形成的?
    1. What causes a wave to break at the shore?
      ::是什么导致海浪在岸边破裂?