Some countries have a large number of earthquakes. Japan is one of them, while others do not have many, for example, there are few earthquakes in Britain. There is often a great noise during an earthquake. The ground vibrates (颤动)．Houses fall down. Railways are broken, which causes trains to turn over. Sometimes thousands of people are killed in different ways. About 60，000 were killed in 1783 in the south of Italy.

Some people say that earthquakes often happen near volcanoes (火山), but it is not true. The centers of some earthquakes are under the sea. The bottom of the sea suddenly moves. The powerful forces inside the earth break the rocks. The coast is shaken and great waves appear. These waves travel long distances and rush over the land when they reach it, breaking down houses and other buildings. Sometimes they break more buildings than the earthquake itself.

A terrible earthquake happened in Assam, India, in 1986.The land near Shillong suddenly moved 1.5 feet to one side, and then back again. It continued to act like this 20 times a minute. Few buildings could stand what was happening and the great stones flew four feet up into the air. What kind of building stays up best in an earthquake? The Americans carefully studied the results of the earthquake at San Francisco (1906) and believed it best for buildings to be made with concrete (混凝土) walls together by steel frames. Such are the buildings that canˈt burn or fall easily.

El Nino, a Spanish term for “the Christ child”, was named by South American fisherman who noticed that the global weather pattern, which happens every two to seven years, reduced the amount of fishes caught around Christmas. El Nino sees warm water, collected over several years in the western Pacific, flows back eastwards when winds that normally blow westwards weaken, or sometimes the other way round.

The weather affects both good and bad, are felt in many places. Rich countries gain more from powerful Nino, on balance, than they lose. A study found that a strong Nino in 1997 helped American’s economy grow by 15 billion, partly because of better agricultural harvest, farmers in the Midwest gained from extra rain. The total rises in agricultural in rich countries in growth more than the fall in poor ones.

But in Indonesia extremely dry forests are in flames. A multi-year drought (干旱）in south-east Brazil is becoming worse. Though heavy rains brought about by El Nino may relieve the drought in California, they are likely to cause surface flooding and other disasters.

The most recent powerful Nino, in 1997-98, killed around 21,000 people and caused damage worth $36 billion around the globe. But such Nino come with months of warning, and so much is known about how they happen that governments can prepare. According to the Overseas Development Institute (ODI), however, just 12% of disaster-relief funding in the past two decades has gone on reducing risks in advance, less than recovery and rebuilding afterwards. This is despite evidence that a dollar spent on risk-reduction saves at least two on reconstruction.

Simple improvements to infrastructure (基础设施）can reduce the spread of disease. Better sewers (下水道）make it less likely that heavy rain is followed by an outbreak of the disease of bad stomach. Stronger bridges mean villages are less likely to be left without food and medicine after floods. According to a paper in 2011 by Mr. Hsiang and co-authors, civil conflict is related to El Nino’s harmful effects—and the poorer the country, the stronger the link. Though the relationship may not be causal, helping divided communities to prepare for disasters would at least reduce the risk that those disasters are followed by killing and wounding people. Since the poorest are least likely to make up for their losses from disasters linked to El Nino, reducing their losses needs to be the priority.

Amazing Facts About Elf Owls

    The elf owl is mostly found in the southwestern parts of the United States and Mexico. During the spring and summer seasons, it moves to Arizona and New Mexico. It returns to Mexico for the winter. The elf owl doesnˈt build its own nest. It lives in tree holes.

    The elf owl is a yellow bird with dark wings. Its eyes are bright yellow and its feet are large. It is the smallest owl of the species, only about 12.5-14.5 centimeters long. It is also the worldˈs lightest owl, weighing not more than forty grams. In general, female elf owls weigh more than male ones.

    The female usually lays three eggs at a time. After the young elf owls are born, their mother will feed them with worms for up to three to four weeks. After 10 weeks, the young ones are fully grown and ready to take flight.

    The elf owls do not behave in a threatening way. When danger comes, they will fly away in the other direction, rather than staying and facing the danger or their enemies. Besides flying, the elf owl can also walk and climb like a parrot. The elf owl is most active after dusk, during the night and just before dawn. It can produce many different kinds of sounds. It can live for three to six years in the wild. If they are kept in cages, they can live for ten to fourteen years. The elf owls are now in danger because of the loss of habitat. Cutting down trees will result in lack of places for them to live in.

El Nifio, a Spanish term for “the Christ child”, was named by South American fisherman who noticed that the global weather pattern, which happens every two to seven years, reduced the amount of fishes caught around Christmas. El Nifio sees warm water, collected over several years in the western Pacific, flow back eastwards when winds that normally blow westwards weaken, or sometimes the other way round.

The weather effects both good and bad, are felt in many places. Rich countries gain more from powerful Nifio, on balance, than they lose. A study found that a strong Nifio in 1997-98 helped American’s economy grow by 15 billion, partly because of better agricultural harvest, farmers in the Midwest gained from extra rain. The total rise in agricultural incomes in rich countries is greater than the fall in poor ones.

But in Indonesia extremely dry forests are in flames. A multi-year drought in south-east Brazil is becoming worse. Though heavy rains brought about by El Nino may relieve the drought in California, they are likely to cause surface flooding and other disasters.

The most recent powerful Nino, in 1997-98, killed around 21,000 people and caused damage worth $36 billion around the globe. But such Ninos come with months of warning, and so much is known about how they happen that governments can prepare. According to the Overseas Development Institute (ODI), however, just 12% of disaster-relief funding in the past two decades has gone on reducing risks in advance, rather than recovery and rebuilding afterwards. This is despite evidence that a dollar spent on risk-reduction saves at least two on reconstruction.

Simple improvements to infrastructure(基础设施）can reduce the spread of disease. Better sewers(下水道）make it less likely that heavy rain is followed by an outbreak of the disease of bad stomach. Stronger bridges mean villages are less likely to be left without food and medicine after floods. According to a paper in 2011 by Mr Hsiang and co-authors, civil conflict is related to El Nino’s harmful effects—and the poorer the country, the stronger the link. Though the relationship may not be causal, helping divided communities to prepare for disasters would at least reduce the risk that those disasters are followed by killing and wounding people. Since the poorest are least likely to make up for their losses from disasters linked to El Nino, reducing their losses needs to be the priority.

If you look at the night sky, you’ll often see stars moving very quickly. In fact, they move much more quickly than they should according to their size and the laws of physics.

Scientists do not completely understand why the speed of these stars is so high. But many believe the reason is that much of the universe is made of something called “dark matter”. Groups of stars called galaxies(银河系), such as the Milky Way, might even be made up of 90 percent dark matter.

How much something weighs depends on where it is. The same object weighs only half as much on Mars as it does on Earth and almost three times as much on Jupiter. So scientists prefer to talk about the mass of something rather than how much it weighs, because mass does not change. They can work out the mass of galaxies by measuring the distance between them and the speed they move at.

 Recently, Jorge Peñarrubia, a senior academic at Edinburgh University, UK, and his team discovered something interesting: The mass of the Milky Way is only half as much as the mass of another nearby galaxy, Andromeda. This seems strange, and dark matter may explain why.

 Finding out more about dark matter could help us understand how the universe began, but this is not easy. Lots of scientists with different types of expert knowledge are working on the problem. The Edinburgh team is working with the University of British Columbia, Carnegie Mellon University, the NRC Herzberg Institute of Astrophysics and the University of Cambridge.

We can’t see dark matter, it’s very difficult to measure and we can’t find out its mass. Unlike stars, dark matter doesn’t produce or reflect light. But we can make a good guess that it is there because of the way things move and the way light bends. Experts now think dark matter may be very different from the matter that we find on Earth. There may also be five times as much dark matter in the universe as ordinary matter.

 Swiss scientist Fritz Zwicky first gave dark matter its name in the 1930s, and researchers have been looking for it ever since. New ways of finding dark matter will still be needed. Today, technology such as the Large Hadron Collider is collecting more and more information but this technology cannot tell us everything. Investigating dark matter may even mean we will need to start asking questions about the way we look at the universe, including the ideas of Albert Einstein.

    A large powerful autumn snowstorm slowly moved out of Colorado on Thursday and moved toward Nebraska and Kansas，causing terrible conditions on the eastern plains．Hundreds of flights were cancelled (取消) because of the snowstorm．

    The snow dropped more than 3 feet in areas of the foothills west of Denver and closed schools and businesses．Roads across the region remained full of snow and icy．

    “Big storms like these seem to come to America around every 10 to 12 years，”said Kyle Fredin，a National Weather Service meteorologist (气象学家)．

    The storm also spread a blanket of white from northern Utah’s Wasatch Front to western Nebraska’s northern border with South Dakota．Denver based Frontier Airlines said it  cancelled 19 flights in and out of Denver, and some flights were delayed by up to four hours at Denver International Airport．United Airlines，a carrier at the Denver airport with about 400 flights per day，cancelled about half of its flights．The area around the airport received between 11 and 16 inches of snow，the weather service said．Airport spokesman Chuck Cannon said crews were using 174 pieces of snow removal equipment to keep runways and taxiways clear as they dealt with severe (猛烈的) wind gusts.

    “Our biggest problem area now is the eastern plains of Colorado,” said CDOT spokesman Bob Wilson．“One of the biggest conditions we are dealing with is the wind because it makes us unable to see．”He said snowplows (扫雪机) had been removing snow．But the wind is blowing so badly that it will basically just blow more snow onto the roadway,” he added．

    Wilson said no serious accidents had been reported，likely because shuttered businesses meant fewer cars on the road．

    Whiteout conditions were forecast on Thursday for the plains of Wyoming and western Nebraska，where 12 inches of snow were reported in Rushville and 11 inches nearby Clinton．Three-foot drifts were reported elsewhere in western Nebraska．

Australia--a huge island continent that lies to the south of Asia. Australia－more than two hundred years old, a nation that is still growing.

    Its big cities lie on the southeast coast, this is where most Australians live. Australians prefer to own their own houses, though some live in apartments. Australians are a suburban people. The suburbs surround the cities for many miles, and so efficient transport is of great importance. As the economy grows, so do its industries- a higher level of production, a wider range of products.

    The Australian works hard, but he likes his leisure. The climate makes outdoor activities the most popular.

    Canberra, the capital of Australia, is a planned modem city located inland. Australia is governed by a parliamentary democracy. The representatives of other countries have their embassies here. Australia wants to strengthen relations with her neighbors.

    Australia is a strange land, a land of vast expanses- fertile valleys, snow fields and deserts- also a land with unique animal, many that can not be found on any other continent in the world today.

    Much of the continent is dry, but man has utilized the land, made it productive, with its tools, with its technology. This is the driest continent of all, and water is a precious possession, more precious than all other natural resources. Large dams are built to collect the water, there to irrigate the fields of pastures and crops.

    But Australia is changing. The land of wool and wheat is now a land of large-scale industry and mining. The costs of developing the new mineral discoveries are enormous, but the rewards are great too.

    Australia--a young and developing nation. Australia--a nation that wants to communicate with its neighbors.

 Check out our tsunami facts and learn some interesting information related to these great walls of water that can cause so much destruction．Find out what causes tsunamis and read about some recent examples of tsunamis that have occurred around the globe．

    ■The Japanese word for tsunami means harbor wave．

    ■Tsunamis are sometimes referred to as tidal (受潮汐影响的) waves but this term has fallen out of favor because tsunamis are not related to tides．

    ■Tsunamis are huge waves of water that are usually caused by earthquakes or volcanic eruptions．

    ■As a tsunami approaches the shore (海岸)，water may move back from the coast．If it is

shallow (浅的) enough，the water may be pulled back hundreds of meters．If you are in the area，you can know that a tsunami is on the way when you see this phenomenon．

    ■Regions in tsunami danger zones often have warning systems in place to give people as much time as possible to move to a safe place．

    ■When tsunamis hit shallow water (often near the coast) they slow down but increase in height．

    ■An earthquake in the Indian Ocean off Indonesia in December 2004 caused a tsunami that killed over 200,000 people in 14 countries．

    ■In March 2011，the Tohoku earthquake off the eastern coast of Japan caused a tsunami that was a major factor in the death of over 15,000 people．

    ■The tsunami waves created by the Tohoku earthquake reached heights of over 40 meters in some areas，wiping out coastal towns and causing a number of nuclear accidents．