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There are seacoasts and deserts, flatlands and mountains. The West Coast is forward the Pacific Ocean, which is relatively tranquilize. The East Coast is along the Atlantic Ocean, which is known for its hurricanes. These strike chiefly the southeastern states.
Some chasers do it just because it is their idea of fun. Others do it to help document storms and warn the public. Still others are part of weather research teams.
Tornadoes can be measured using wind speed information from Doppler radar systems. Tornadoes usually travel in a northeasterly instruction with a speed of thirty-two to sixty-four kilometers an hour. But they have been reported to push in additional directions and as rapid as one hundred seventeen kilometers an hour.
KATHERINE COLE: With a hurricane, bigger does no necessarily average stronger. Large tornadoes can be weak. And some of the smallest tornadoes can be the most damaging. But no material what the size, tornado winds are the strongest ashore Earth. Tornadoes have been understood apt carry trees, motorcars or families from 1 location apt another. They can too devastate everything in their path.
KATHERINE COLE: In the United States, the force of a tornado is judged by the damage to structures. Scientists inspect the damage before they estimate the severity of a tornado. They measure tornadoes on the Enhanced Fujita scale or the EF scale.
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BOB DOUGHTY: Some people make a sport out of watching and emulating tornadoes. They are called tornado chasers or storm chasers. Their work can be seen in the utmost weather videos that are increasingly renowned on TV and on the Internet.
Tornadoes that fashion over water are phoned waterspouts. But tornadoes cover a much smaller area than typhoons, which form over oceans.
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A "tornado explosion" is often defined as 6 or more tornadoes produced by the same weather system among a daytime. But the outbreak of April third and fourth, nineteen seventy-four, set a citizen disc. It is memorized as the "Super Outbreak." One hundred forty-eight tornadoes struck during a twenty-four-hour phase. More than three hundred people were killed and approximately six thousand others impaired.
BOB DOUGHTY: Tornado season has begun in the United States. Violent storms struck several parts of the country last week. The National Weather Service said there were ten reports of tornadoes across the central and southern Plains states last Thursday.
Tornadoes form when winds blowing in different directions meet in the clouds and begin to turn in circles. Warm air rising from below causes the wind tube to reach toward the ground. Because of their circular movement, these windstorms are also known as twisters.
One tornado that was principally ruinous hit Xenia,ralph lauren pas cher, Ohio. The sound you are about to hear comes from the Web site www.xeniatornado.com. It is one man's recording of the tornado moving closer.
Tornadoes can strike with little or no warning. Most injuries happen when flying objects hit people. Experts say the best place to be is in an underground shelter, or a small, windowless room in the lowest part of a architecture.
BOB DOUGHTY: Tornado season has begun in the United States. Violent storms struck several parts of the country last week. The National Weather Service said there were ten reports of tornadoes across the central and southern Plains states last Thursday.
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BOB DOUGHTY: Tornadoes are observed most often in the central part of the United States,doudoune moncler, where the land is mostly flat. The area where the most violent tornadoes usually happen is known as “Tornado Alley.” This area is considered to extend from north central Texas to North Dakota.
Tornadoes form when winds beating in alter directions encounter in the clouds and start to rotate in circles. Warm air rising from below causes the wind tube to reach toward the ground. Because of their circuitous movement, these windstorms are also known as twisters.
Tornadoes can happen any period of the year. But most happen from late winter to the navel of summer. In some areas, there is a second high season in autumn.
Ted Fujita was a weather expert who developed a system to rate tornados in the nineteen seventies. The EF scale is a set, or collection, of wind estimates. They are based on levels of damage to twenty-eight different kinds of structures and other objects. Tornadoes that cause only light damage are called an EF-zero. Those with the highest winds that destroy well-built homes and throw vehicles great distances are called an EF-five.
There are seacoasts and deserts, flatlands and mountains. The West Coast is along the Pacific Ocean, which is relatively calm. The East Coast is along the Atlantic Ocean, which is known for its hurricanes. These strike mainly the southeastern states.
BOB DOUGHTY: The tornado reporting system involves watches and warnings. A tornado watch means tornadoes are possible in the area. A tornado warning means that a tornado has been seen. People are told to take shelter immediately.
Even a weak tornado requires the right combination of wind, temperature, pressure and humidity. Weather experts can identify these conditions. And, when they observe them,abercrombie, they can advise people that tornadoes might develop. But they are not able to tell exactly where or when a tornado will hit. Tornado warnings still depall over large part on human observations.
KATHERINE COLE: This is SCIENCE IN THE NEWS in VOA Special English. I'm Katherine Cole.
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Yet tornadoes can be difficult to see. Sometimes only the objects they are carrying through the air can be seen. Some night-time tornadoes have been observed because of lightning strikes nearby. But tornadoes at night are usually impossible to see.
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The National Oceanic and Atmospheric Administration keeps records of tornado sightings. It says tornadoes kill eighty people and injure one thousand five hundred others nationwide in an average year.
KATHERINE COLE: No two tornadoes look exactly the same. And no two tornadoes act the same way.
BOB DOUGHTY: The deadliest American tornado on record was the Tri-State Tornado of March eighteenth, nineteen twenty-five. It tore across Missouri, Illinois and Indiana. About seven hundred people were killed.
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KATHERINE COLE: No two tornadoes see exactly the same. And no two tornadoes deed the same way.
KATHERINE COLE: This is SCIENCE IN THE NEWS in VOA Special English. I'm Katherine Cole.
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People driving during a tornado are told to find low ground and arrange flat, facedown, with their hands covering their brain. People in the path of a tornado often equitable have minutes to make life-or-death decisions.
KATHERINE COLE: Tornado seasons are the result of wind and weather patterns. During spring, warm air moves north and mixes with cold air remaining from winter. In autumn, the opposite happens. Cold weather moves south and combines with the last of the warm air from summer.
BOB DOUGHTY: This SCIENCE IN THE NEWS was written by Brianna Blake. June Simms was our producer. I'm Bob Doughty.
BOB DOUGHTY: This SCIENCE IN THE NEWS was written by Brianna Blake. June Simms was our maker. I'm Bob Doughty.
KATHERINE COLE: The National Weather Service says the United States gets more severe weather than whichever other country. For one thing, it is also bigger than most other countries. And it has numerous different conditions that establish numerous different kinds of weather.
KATHERINE COLE: The National Weather Service says the United States gets more severe weather than any other country. For one thing, it is also bigger than most other countries. And it has many different conditions that create many different kinds of weather.
Tornadoes can be measured using wind speed information from Doppler radar systems. Tornadoes usually travel in a northeasterly direction with a speed of thirty-two to sixty-four kilometers an hour. But they have been reported to move in other directions and as fast as one hundred seventeen kilometers an hour.
BOB DOUGHTY: The deadliest American tornado on record was the Tri-State Tornado of March eighteenth, nineteen twenty-five. It tore across Missouri, Illinois and Indiana. About seven hundred people were killed.
A "tornado outbreak" is often defined as six or more tornadoes produced by the same weather system within a day. But the outbreak of April third and fourth, nineteen seventy-four, set a national record. It is remembered as the "Super Outbreak." One hundred forty-eight tornadoes struck during a twenty-four-hour period. More than three hundred people were killed and nearly six thousand others injured.
Tornadoes that form over water are called waterspouts. But tornadoes cover a many smaller area than hurricanes, which form over oceans.
Tornadoes have been observed on every continent except Antarctica. But experts say they are most commonly seen in the United States. On average, eight hundred tornadoes are reported nationwide each year.
BOB DOUGHTY: And I'm Bob Doughty. This week, we will tell about the science of tornadoes. Tornadoes have been observed in many parts of the world. But the storms are most often found in the United States.
BOB DOUGHTY: Tornadoes are observed most often in the chief part of the United States, where the land is mostly flat. The space where the most violent tornadoes ordinarily occur is known for "Tornado Alley." This district is thought to amplify from northwardly central Texas to North Dakota.
Even a weak tornado requires the right fusion of wind, temperature,ralph lauren, oppression and moisture. Weather specialists can nail these conditions. And, when they inspect them, they can advise human namely tornadoes might amplify. But they are not competent to acquaint exactly where or when a tornado will hit. Tornado omens still depend in colossal portion on people observations.
Tornadoes can buffet with little or no warning. Most injuries happen when flying objects hit people. Experts mention the best place to be is in an underground asylum,abercrombie, or a small, windowless chamber in the lowest part of a establishing.
A film about the VORTEX2 project opened at some theaters in the United States last month. The film includes never before seen images of tornadoes. To safely capture up-close film footage of tornadoes, some project participants traveled in a seven-ton, armored tornado intercept vehicle directly into tornadoes as they formed.
BOB DOUGHTY: And I'm Bob Doughty. This week, we will tell about the science of tornadoes. Tornadoes have been observed in many parts of the world. But the storms are most often found in the United States.
One tornado that was especially destructive hit Xenia, Ohio. The sound you are about to hear comes from the Web site www.xeniatornado.com. It is one man's recording of the tornado moving closer.
BOB DOUGHTY: The tornado reporting system involves watches and warnings. A tornado see manner tornadoes are feasible in the area. A tornado warning method that a tornado has been seen. People are told to take shelter quickly.
A movie about the VORTEX2 project opened at some cinemas in the United States last month. The movie includes not before seen images of tornadoes. To safely occupy up-close movie footage of tornadoes, some project participants traveled in a seven-ton, armored tornado intercept traffic directly into tornadoes as they formed.
KATHERINE COLE: With a tornado, bigger does not necessarily mean stronger. Large tornadoes can be weak. And some of the smallest tornadoes can be the most damaging. But no matter what the size,polo ralph lauren, tornado winds are the strongest on Earth. Tornadoes have been known to carry trees, cars or homes from one place to another. They can also destroy anything in their path.
The most severe tornadoes can reach wind speeds of three hundred twenty kilometers an hour or more. In some cases, the resulting paths of damage can stretch more than a kilometer wide and eighty kilometers long.
18 April 2011
Some chasers do it just because it is their idea of fun. Others do it to help document storms and warn the public. Still others are part of weather research teams.
KATHERINE COLE: Tornado seasons are the result of wind and weather patterns. During spring, lukewarm air moves north and mixes with chilly air remaining from winter. In autumn, the opposite happens. Cold weather moves south and combines with the final of the warm air from summer.
Yet tornadoes can be difficult to penetrate. Sometimes only the objects they are carrying via the atmosphere can be seen. Some night-time tornadoes have been observed because of speedy strikes contiguous. But tornadoes at night are usually impossible to see.
BOB DOUGHTY: Some people make a sport out of watching and following tornadoes. They are called tornado chasers or storm chasers. Their work can be seen in the extreme weather videos that are increasingly popular on television and on the Internet.
Recently, an international team of scientists completed a tornado research project called VORTEX2. More than one hundred researchers traveled throughout America’s Great Plains in two thousand nine and two thousand ten. They used weather measurement instruments to collect scientific information about the life of a tornado. The goal of the project was to examine in detail how tornadoes are formed and the kinds of damage they cause.
A colossal tornado funnel cloud touches down in Orchard, Iowa, Tuesday, June 10,moncler, 2008. The Globe Gazette and Mitchell County Press News reported that Lori Mehmen of Orchard, took the photo from outdoor her front gate.Recently,coach handbags, an international group of scientists completed a tornado research project called VORTEX2. More than one hundred researchers voyaged throughout Americas Great Plains in two thousand 9 and two thousand ten. They accustom weather measurement instruments to collect scientific message about the life of a tornado. The goal of the project was to examine in elaborate how tornadoes are formed and the kinds of damage they occasion.
Nathaniel Ramey, left, solaces Megan Hurst at her grandmother's house in Askewville, North Carolina, later a tornado struck April 16,moncler, 2011Ted Fujita was a weather expert who adult a system to rate tornados in the nineteen seventies. The EF scale is a set, or collection, of wind estimates. They are based on levels of damage to twenty-eight different kinds of structures and other objects. Tornadoes that cause only light damage are called an EF-zero. Those with the maximum winds that destroy well-built homes and discard vehicles large distances are called an EF-five.
Tornadoes can happen any time of the year. But most happen from late winter to the middle of summer. In some areas, there is a second high season in autumn.
KATHERINE COLE: And I'm Katherine Cole. Read and listen to our programs at voaspecialenglish.com. And whether you have a science answer, mail it to [email protected]. We might reply it on our program. Join us repeatedly next week as more news about science, in Special English, on the Voice of America.
Tornadoes have been observed on every continent besides Antarctica. But experts say they are most commonly seen in the United States. On average, 8 hundred tornadoes are reported nationwide each year.
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Usually a community will receive a warning at least a few minutes before a tornado strikes. But each year there are some surprises where tornadoes develop when they are least expected.
A car sits in a drainage ditch in Colerain, North Carolina after a tornado ripped through the area SaturdayA tornado is a violently turning tube of air suspended from a thick cloud. It extends from a thunderstorm in the sky down to the ground. The shape is favor a funnel: wide at the altitude, narrower at the base.
The National Oceanic and Atmospheric Administration reserves records of tornado sightings. It says tornadoes kill eighty people and injure one thousand five hundred others nationwide in an mean year.
A tornado is a violently turning tube of air suspended from a thick cloud. It extends from a thunderstorm in the sky down to the ground. The shape is like a funnel: wide at the top, narrower at the bottom.
The most caustic tornadoes can reach wind speeds of three hundred twenty kilometers one hour or extra. In some cases, the resulting paths of harm can extend more than a kilometer wide and eighty kilometers long.
Usually a community will receive a warning at least a few minutes before a tornado strikes. But each year there are some wonders where tornadoes develop when they are fewest expected.
People driving during a tornado are told to find low ground and lay flat,coach outlet, facedown, with their hands covering their head. People in the path of a tornado often just have minutes to make life-or-death decisions.
KATHERINE COLE: In the United States, the force of a tornado is judged by the damage to architectures. Scientists inspect the damage before they estimate the severity of a tornado. They amount tornadoes on the Enhanced Fujita scale or the EF scale.
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