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  • General

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  • 潮汐

    A detailed sandcastle built on a beach near the water's edge.

     

    Did you ever build a sandcastle?
    ::你造过沙堡吗?

    A sandcastle only lasts until the next  tide  comes in. To build a sand castle the sand must be moist enough for the grains to stick together. So it has to be near the  water . But that puts the castle in position to be buried by the next  high tide . Oh well. You can build another one when the tide goes back out!
    ::沙堡只能持续到下一场潮期。 要建造一座沙城堡, 沙丘必须足够湿润, 以便能凝聚粮食。 因此, 它必须靠近水面 。 但这将使城堡在下一场高潮下可以被掩埋。 哦, 当潮退后, 你可以再建一座!

    Tides
    ::梯度

    Tides  are daily changes in the level of ocean water. They occur all around the globe.  High tides  occur when the water reaches its highest level in a  day .  Low tides  occur when the water reaches its lowest level in a day. Tides keep cycling from high to low and back again. In most places the water level rises and falls twice a day. So there are two high tides and two low tides approximately every 24 hours.
    ::潮汐是海洋水水平的日常变化,它们在全球各地发生。当水在一天中达到最高水平时,潮汐会高涨。当水在一天中达到最低水平时,潮汐会低涨。潮汐会不断从高到低和回循环。在大多数地方,水位一天上升两次。因此,每24小时大约会有两次高潮和两次低潮。

    Below, you can see the difference between high and low tides ( Figure   ). This is called the  tidal range .
    ::下面,您可以看到高潮和低潮之间的差别(图)。这叫做潮汐范围。

    Comparison of high and low tides near a harbor showing water level differences.

     

    Where is the intertidal zone in this picture?
    ::照片中的潮间地带在哪里?

    Why Tides Occur
    ::为何铁铁矿石

    The figure below shows why tides occur ( Figure   ). The main cause of tides is the pull of the Moon’s gravity on Earth. The pull is greatest on whatever is closest to the Moon. Although the gravity pulls the land, only the water can move. As a result:
    ::下图显示了潮涨的原因(图 ) 。 潮涨的主要原因是月球在地球的引力拉动。 最接近月球的拉力最大。 尽管引力拉动了陆地,但只有水能移动。 结果:

    • Water on the side of Earth facing the Moon is pulled hardest by the Moon’s gravity. This causes a bulge of water on that side of Earth. That bulge is a high tide.
      ::面对月球的地球一侧的水受月球引力的拉力最大,这在地球的另一侧造成了水的暴涨。 暴涨是一个高涨的潮汐。
    • Earth itself is pulled harder by the Moon’s gravity than is the ocean on the side of Earth opposite the Moon. As a result, there is bulge of water on the opposite side of Earth. This creates another high tide.
      ::地球本身受到月球引力的拉力比月球对面地球边的海洋更强。 结果,地球对面的水会膨胀。 这又产生了另一个高潮。
    • With water bulging on two sides of Earth, there’s less water left in between. This creates low tides on the other two sides of the  planet .
      ::随着地球两侧水的涌现,中间的水少了。 这造成了地球另外两侧的低潮。

    Earth and Moon, depicting high and low tides caused by gravity.

     

    High and low tides are due mainly to the pull of the Moon’s gravity.
    ::高潮和低潮主要归因于月球引力的拉动。

    Spring Tides and Neap Tides
    ::春季硫化物和破粒硫化物

    The Sun’s gravity also pulls on Earth and its oceans. The   is much larger than the Moon, so is its gravitational pull on Earth greater than the Moon’s? The pull of the Sun’s gravity is much less because the Sun is much farther away. In  fact , the Sun’s gravitational pull on Earth is a little less than half of the Moon's pull. 
    ::太阳的引力还拉动着地球及其海洋。 太阳的引力比月球大得多,它的引力拉动着地球的引力拉动也比月球大得多吗?太阳的引力拉动要小得多,因为太阳离地球远得多。 事实上,太阳对地球的引力拉动还不到月球拉动的一半。

    The figure below shows where the Moon is relative to the Sun at different times during the month ( Figure   ). The positions of the Moon and Sun relative to each other affects the tides. This creates spring tides or neap tides.
    ::下图显示了月中月亮与太阳在不同时间相对的位置(图 ) 。 月亮和太阳相对的位置会影响潮汐, 从而产生春潮或破浪。

    • Spring tides  occur during the  new moon  and  full moon . The Sun and Moon must either be in a straight line on the same side of Earth, or they must be on opposite sides of Earth. Their gravitational pull combines to cause very high and very low tides. Spring tides have the greatest tidal range.
      ::春潮发生在新月和满月期间。 太阳和月亮必须位于地球同一侧的直线, 或者它们必须位于地球的对面。 它们的引力拉动合在一起导致极高和极低的潮汐。 春季潮汐的潮汐范围最大。
    • Neap tides  occur during the first and third quarters of the Moon. The Moon and Sun are at right angles to each other. Their gravity pulls on the oceans in different directions so the highs and lows are not as great. Neap tides have the smallest tidal range.
      ::月球第一季度和第三季度时会出现低潮,月球和太阳在正对方向,它们引力从不同方向拉向海洋,因此海平面和海平面没有那么大。低潮的潮汐范围最小。

    The relationship between the Moon and Sun affecting Earth's tides.

     

    The Sun and Moon both affect Earth’s tides.
    ::太阳和月亮都影响着地球的潮汐。

    Studying ocean tides' rhythmic movements helps scientists understand the ocean and the Sun/Moon/Earth system. This QUEST video explains how tides work, and visits the oldest continually operating tidal gauge in the  Western Hemisphere .
    ::研究海洋潮汐的节奏运动有助于科学家了解海洋和太阳/月球/地球系统。 QUEST视频解释了潮汐是如何运作的,并参观了西半球最古老的不断运行的潮汐测量仪。

    Summary
    ::摘要

    • The primary cause of tides is the gravitational attraction of the Moon. This causes two high and two low tides a day.
      ::潮汐的主要起因是月球的引力吸引力,这导致每天两次高潮和两次低潮。
    • When the Sun's and Moon's tides match, there are spring tides. When the two tides are opposed, there are neap tides.
      ::当太阳和月亮的潮水吻合时,就会有春季的潮水。当两种潮水相互对立时,就会有微小的潮水。
    • The difference between the daily high and the daily low is the tidal range.
      ::每天高与每天低之间的差别是潮汐范围。

    Review
    ::回顾

    1. How does the Moon make two high and two low tides a day?
      ::月球如何一天两次高两次低潮?
    1. How does the Sun make two high and two low tides a day?
      ::太阳如何一天两次高两次低潮?
    1. What causes spring tides? What causes neap tides?
      ::是什么导致春季潮流?什么导致暴涨?