海洋风暴和大自然力量的科学
CHRISTOPHER CRUISE: This isSCIENCE IN THE NEWSinVOA Special English. I'm Christopher Cruise.
SHIRLEY GRIFFITH: And I'mShirley Griffith.
Today we tell about the science of severeocean storms.
今天我们谈论有关严重海洋风暴的科学。
Severeocean stormsthat develop over the Indian Ocean are called cyclones. (旋风)
源自印度洋的严重海洋风暴称为旋风。
Storms that form over the northwestern Pacific Ocean are typhoons. (台风)
在西北太平洋形成的风暴是台风。
And storms that form over the eastern Pacific Ocean and the Atlantic Ocean are hurricanes(飓风).
在东太平洋和大西洋上形成的风暴是飓风。
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CHRISTOPHER CRUISE:
A storm with a misleadingly pleasant name recently brought death and destruction to parts of North America.
一个有误导性的好听名字的风暴最近对北美部分地区造成了破坏,并造成了人员死亡。
Wide, slow-movingHurricaneIrene began to organize over the Lesser Antilles Islands in the Caribbean Sea.
范围广阔、缓慢移动的飓风艾琳在加勒比海的xxx群岛上空形成。
Later Irene gained strength.
然后艾琳积聚了力量。
The storm stretched about one thousand seven hundred seventy kilometers along the eastern United States.
风暴沿美国东部伸展达到了1770公里。
Its destructive winds and heavy rain reached farinland.
具有破坏性的风和暴雨深入到内陆。
Even after it weakened, Irene carried disaster as far north as Quebec and Nova Scotia in Canada.
甚至在其变弱以后,艾琳还给北部的加拿大的Quebec和Nova Scotia带来了破坏。
A storm survivor in New England made a prediction as he repaired storm damage to his property.
在新英格兰的暴风幸存者在他修复受到暴风雨破坏的财产时做了预测。
He said he believes fewer people will name their children "Irene" after this storm.
他说他认为在这次暴风雨后很少会有人给孩子取名叫艾琳。
Something similar happened afterHurricaneKatrina struck the south central United States in .
类似事情发生在飓风Katrina袭击美国中南部后。
America's Social Security Administration says far fewer parents named their newborn daughters Katrina in the years immediately after the storm.
美国社会安全局称很少的父母在暴风雨后的几年里为新出生的女儿起Katrina的名字。
SHIRLEY GRIFFITH: People have called some natural events by human names for centuries.
人们几个世纪以来已经用人名来称呼一些自然事件了。
For example, the name "Thor" was given to the mythical Norse god of thunder, the loud sound that follows lightning in the sky.
An Australian scientist began calling storms by women's names before the end of the nineteenth century.
During World War Two, scientists called storms by the names of their wives or girlfriends.
American weather experts started to use women's names for storms in nineteen fifty-three.
In nineteen seventy-nine, they began to use men's names, too.
CHRISTOPHER CRUISE: Scientists decide on lists of names years in advance.
They decide on them at meetings of the World Meteorological Organization.
他们在世界气象学组织大会上确定暴风的名字列表。
The NationalHurricaneCenter in Miami, Florida has one list for each of six years for AtlanticOcean storms.
The experts there name storms when they reach wind speeds of sixty-two kilometers an hour.
当风速达到每小时62公里时,专家就为暴风雨命名。
That is true even if they never grow stronger.
The first name used in a storm season begins with the letter A.
The second begins with B and so on.
The letters Q, V, X, Y and Z are never used.
And the same list of names is not used again for at least six years.
And different lists are used for different parts of the world.
A name is retired when the storm with this name has been very destructive.
In two thousand five, Greek letters had to be used for the first time to name storms in the Atlantic.
That was the plan -- to call storms Alpha, Beta and so on -- if there were ever morethan twenty-onenamed storms in a season.
As it happened, there were twenty-eight.
SHIRLEY GRIFFITH: The two thousand five Atlantichurricaneseason was the first on record to have fifteen hurricanes.
大西洋飓风季是第一个有15次飓风的记录。
Four reached Category Five strength, also a first.
其中四个达到了五类强度,也是第一次。
And the National Oceanic and Atmospheric Administration says it was the first season
when four major hurricanes hit the United States.
The most destructive was Katrina.
It was blamed for more than one thousand eight hundred deaths along the Gulf of Mexico.
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CHRISTOPHER CRUISE:
Ocean stormsdevelop when the air temperature in one area is different from the temperature nearby.
Warmer air rises, while cooler air falls. These movements create a difference in atmospheric pressure.
If the pressure changes over a large area, winds start to blow in a huge circle.
High-pressure air is pulled toward a low-pressure center.
Thick clouds form and heavy rains fall as the storm gains speed and moves over the ocean.
Storms can get stronger as they move over warm ocean waters.
The strongest, fastest winds of ahurricaneblow in the area known as the eyewall.
It surrounds the center, or eye, of the storm. The eye itself is calm by comparison.
SHIRLEY GRIFFITH:
Wind speeds in the most severeocean stormscan reach more than two hundred fifty kilometers an hour.
Up to fifty centimeters of rain can fall.
Some storms have produced more than one hundred fifty centimeters of rain.
These storms also cause high waves and ocean surges.
A surge is a continuous movement of water that may reach as high as six meters or more.
The water strikes low coastal areas.
Surges are commonly responsible for about ninety percent of all deaths fromocean storms.
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CHRISTOPHER CRUISE: The NationalHurricaneCenter in Miami keeps close watch on severe storms.
It works with government officials and with radio and television stations to keep people informed.
Experts believe this early warning system has helped reduce deaths fromocean stormsin recent years.
But sometimes people cannot or will not flee the path of a storm.
That is what happened in many places in Louisiana whenHurricaneKatrina struck.
Studies have shown that some people do not leave a storm-threatened area
because they have no transportation or money for transportation.
Another reason is that they fear that their property will be damaged by other people, if not by the storm.
Still another is that people do not want to leave their pets or farm animals.
Today, more plans exist for animal care during severe storms than in years before.
SHIRLEY GRIFFITH: Weather experts use computer programs to create models that show where a storm might go.
The programs combine information such as temperatures, wind speed,
atmospheric pressure and the amount of water in the atmosphere.
Scientists collect the information with satellites, weather balloons and devices floating in the oceans.
They also receive information from ships and passenger airplanes and other flights.
Government scientists use specially-equipped planes to fly into and around storms.
The crews drop instruments tied to parachutes.
The instruments collect information about temperature, pressure and wind speed.
CHRISTOPHER CRUISE:
Scientists use the Saffir-SimpsonHurricaneScale to measure the intensity of storms based on wind speed.
科学家使用飓风量度来测量风暴基于风速的强度。
The scale provides an idea of the amount of coastal flooding and property damage that might be expected.
The scale is divided into five groups or categories.
The mildesthurricaneis a category one.
It has winds of about one hundred twenty to one hundred fifty kilometers an hour.
This storm can damage trees and lightweight structures. It can also cause flooding.
Wind speeds in a category twohurricanecan reach close to one hundred eighty kilometers an hour.
These storms are often powerful enough to break windows or blow the tops off houses.
SHIRLEY GRIFFITH:
Winds between about one hundred eighty and two hundred fifty kilometers an hour represent categories three and four.
A more powerful storm is a category fivehurricane.
Researchers say forces other than wind speed help cause extensive destruction.
And the lower the air pressure, the stronger the storm.
HurricaneIrene's most damaging power, however, came from water.
In some areas of Vermont, for example, storm surges caused record flooding.
In all, Irene was blamed for more than forty deaths in the United States.
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CHRISTOPHER CRUISE: Some scientists believe climate change affects major storms.
一些科学家认为气象变化影响了主要的风暴。
They say the warming of Earth's atmosphere is alreadymaking the storms worse.
Other scientists have published studies that disagree.
Last year, a special committee of the World Meteorological Organization reported on severe storms.
The committee's work appeared in the journal "Nature Geoscience."
Ten scientists wrote the report.
They represented both sides of the debate about global warming.
The scientists reached no clear answer about whether rising temperatures on Earth had already intensified storms.
Still, they made some predictions.
SHIRLEY GRIFFITH: The committee said global warming might cause more powerfulocean stormsin the future.
It said the overall strength of storms measured by wind speed might increase two to eleven percent by the year twenty-one hundred.
And there might be an increase in the number of the most severe storms.
最严重风暴的数目可能会有所增加。
But there might be fewer weak and moderate storms.
然而,可能会有较弱或温和的风暴。
The current Atlantic Oceanhurricaneseason began in June.
此次大西洋飓风季开始于6月。
A tropical storm killed eleven people in Mexico.
在墨西哥,一个热带风暴杀死了11个人。
But experts say none of the first eight named storms of the season gainedhurricanestrength.
但专家称本季最初的八个命名风暴都没有达到飓风的强度。
That set a record. Then, in late August, cameHurricaneIrene.
那创造了记录。然后在8月下旬,飓风艾琳来临了。
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CHRISTOPHER CRUISE: ThisSCIENCE IN THE NEWSwas written byJerilyn Watson.
June Simms was our producer. I'm Christopher Cruise.
SHIRLEY GRIFFITH: And I'mShirley Griffith.
Listen again next week for more news about science inSpecial Englishon the Voice of America.