Tsunamis  海啸

1 A tsunami is a very large ocean wave, which is caused by an underground earthquake. The word tsunami means ‘harbour wave’ in Japanese. A tidal wave is different. It is caused by the force of the moon, sun or planets or by the wind along with it. The water flows straight during a tsunami. This is different from the way ordinary waves flow. They flow in a circular pattern. This straight movement of the tsunami causes a great deal of damage to the land.
1 海啸是由地下地震引起的非常大的海浪。海啸这个词在日语中的意思是“海港波”。潮汐是不同的。它是由月亮、太阳或行星的力量或随之而来的风引起的。海啸期间水笔直流动。这与普通波浪的流动方式不同。它们以圆形模式流动。海啸的这种直线运动对土地造成了很大的破坏。

2 Tsunamis begin due to a movement of the seafloor. They can be caused by an earthquake, a volcano, a meteorite or a big landslide into the ocean or under it. They can occur along a fault line in the earth’s crust where there is a movement of the plates below the sea. These plates can crash together producing large forces of water. Usually, two tsunamis a year occur around the world near the source of the earthquake or another movement. About every fifteen years, a huge tsunami happens which can affect the waters worldwide.
2 海啸是由于海底运动而开始的。它们可能是由地震、火山、陨石或进入海洋或海洋下的大型山体滑坡引起的。它们可能发生在地壳的断层线上，那里的板块在海底有运动。这些板可以碰撞在一起，产生很大的水力。通常，世界各地每年发生两次海啸，靠近地震或其他运动的源头。大约每 15 年就会发生一次巨大的海啸，这可能会影响世界各地的水域。

3 About ten to fifteen percent of earthquakes, which cause damage near their source, are called strike-slip earthquakes. They occur when two blocks of land move horizontally along a fault plane. A fault is a place in the earth’s crust where the plates of the crust have slid past or over one another. The strike-slip earthquake does not cause a tsunami as often as those with a vertical motion.
3 大约有 10% 到 15% 的地震在其源附近造成破坏，称为走滑地震。当两个陆地块沿断层平面水平移动时，就会出现它们。断层是地壳中地壳板块相互滑动的地方。走滑地震不会像垂直运动的地震那样频繁地引起海啸。

4 The speed of the tsunami depends on how deep the water is. Tsunamis travel approximately 475 mph in 15,000 feet of water. In a much less deep amount of water, the speed drops way down. A tsunami wave can travel from Portugal to North Carolina in eight and one-half hours!
4 海啸的速度取决于水的深度。海啸在 15,000 英尺深的水中以大约 475 英里/小时的速度移动。在深度较小的水中，速度会下降很多。海啸波可以在八个半小时内从葡萄牙传播到北卡罗来纳州！

5 The size or height of a tsunami wave can range from an inch to several feet high. It usually cannot even be seen by a ship at sea. When a tsunami comes near land, however, the height can multiply by even ten times. How far inland a tsunami goes can depend upon the features of the shoreline. A tsunami can go inland as much as one mile if the coast is a very flat piece of land at or below sea level.
5 海啸波的大小或高度可以从一英寸到几英尺高不等。通常甚至在海上的船只都看不到它。然而，当海啸靠近陆地时，高度甚至可以增加十倍。海啸向内陆移动多远取决于海岸线的特征。如果海岸是一块非常平坦的土地，位于海平面或海平面以下，则海啸可以向内陆移动长达 1 英里。

6 The tsunami will look like a quickly moving tide coming in or going out from the shore. A wall of water may be seen or large breaking waves. Waves
6 海啸看起来像从岸边进来或流出的快速移动的潮汐。可以看到一堵水墙或巨大的破浪。波
caused by the wind usually have periods between five and fifteen seconds. Waves produced by a tsunami occur between five to sixty minutes. Waves caused by winds also break on the shore. The tsunami wave rolls right in over the land in a flood. The height of a tsunami wave is a rise in the sea level by that much.
由风引起的时间通常在 5 到 15 秒之间。海啸产生的海啸波发生在 5 到 60 分钟之间。风引起的海浪也会在岸边破裂。海啸波像洪水一样卷入大地。海啸波的高度是海平面上升那么多。

7 Signs of an incoming tsunami occur a very little amount of time in advance. A sudden drop in sea level may occur. The ground may shake for twenty seconds or more. Loud, booming noises may be heard.
7 海啸来袭的征兆要提前很短的时间出现。海平面可能会突然下降。地面可能会晃动 20 秒或更长时间。可能会听到响亮的轰鸣声。

8 After an earthquake, scientists can determine the exact time of arrival of a tsunami. These predictions may not be accurate right near the source. Tsunamis farther away may be predicted more accurately using mathematical models from past tsunamis.
8 地震发生后，科学家可以确定海啸到达的确切时间。这些预测可能在源附近不准确。使用过去海啸的数学模型可以更准确地预测距离较远的海啸。

9 A major tsunami occurred in 2011 in Japan. It began in the Pacific Ocean. In 2004, a major tsunami began in the Indian Ocean and affected Asia. Major tsunamis begin along the coast of Alaska every few years. They have had many smaller local tsunamis also. The west coast of the United States and Canada had local tsunamis in 1812, 1873, 1878, 1927, 1930, 1946 and 1949. A great number of tsunamis hit the west coast, which had been generated in other regions. The latest was in 2010. The United States and Canada Atlantic coast has felt the effect of tsunamis also, along with Puerto Rico and the Virgin Islands.
9 2011 年日本发生了一次大海啸。它始于太平洋。2004 年，一场大海啸从印度洋开始，影响了亚洲。阿拉斯加海岸每隔几年就会发生一次大海啸。他们也经历了许多较小的局部海啸。美国和加拿大西海岸在 1812 年、1873 年、1878 年、1927 年、1930 年、1946 年和 1949 年发生了局部海啸。大量海啸袭击了西海岸，这些海啸是在其他地区产生的。最近一次是在 2010 年。美国和加拿大大西洋沿岸以及波多黎各和维尔京群岛也受到了海啸的影响。