单选题 El Nino (厄尔尼诺现象) While some forecasting methods had limited success predicting the 1997 El Nino a few months in advance, the Columbia University researchers say their method can predict large El Nino events up to two years in advance. That would be good news for governments, farmers and others seeking to plan for the droughts and heavy rainfall that El Nino can produce in various parts of the world. Using a computer, the researchers matched sea-surface temperatures to later El Nino occurrences between 1980 and 2000 and were then able to anticipate El Nino events dating back to 1857, using prior sea-surface temperatures. The results were reported in the latest issue of the journal Nature. The researchers say their method is not perfect, but Bryan C. Weare, a meteorologist at the University of California. Davis, who was not involved in the work, said it "suggests El Nino is indeed predictable". "This will probably convince others to search around more for even better methods," said Weare. He added that the new method "makes it possible to predict El Nino at long lead times". Other models also use sea-surface temperatures, but they have not looked as far back because they need other data, which is only available for recent decades, Weare said. The ability to predict the warming and cooling of the Pacific is of immense importance. The 1997 El Nino, for example, caused an estimated $9.0 billion in damage worldwide, offset by beneficial effects in other areas, said David Anderson, of the European Centre for Medium-Range Weather Forecasts in Reading England. "The 1877 El Nino, meanwhile, coincided with a failure of the Indian monsoon and a famine that killed perhaps 40 million in India and China, prompting the development of seasonal forecasting," Anderson said. When El Nino hit in 1991 and 1997, 200 million people were affected by flooding in China alone, according to a 2002 United Nations report. While predicting smaller El Nino events remains tricky, the ability to predict larger ones should be increased to at least a year if the new method is confirmed. El Nino tends to develop between April and June and reaches its peak between December and February. The warming tends to last between 9 and 12 months and occurs every two to seven years. The new forecasting method does not predict any major El Nino events in the next two years, although a weak warming toward the end of this year is possible.

单选题The city centre was Uwiped out /U by the bomb

单选题By far the most common snake in Britain is the adder. In Scotland, in fact, there are no other snakes at all. The adder is also the only Britain snake with a poisonous bite. It can be found almost anywhere, but prefers sunny hillsides and rough open country, including high ground. In Ireland there are no snakes at all. Most people regard snake bites as a fatal misfortune, but not all bites are serious, and very few are fatal: Sometimes attempts at emergency treatment turn out to be more dangerous than the bite itself, with amateurs heroically, but mistakenly, trying do-it-yourself surgery and other unnecessary measures. All snakes have small teeth, so it follows that all snakes can bite, but only the bite of the adder presents any danger. British snakes are shy animals and are far more frightened of you than you could possibly be of them. The adder will attack only if it feels threatened, as can happen if you take it by surprise and step on it accidentally, or if you try to catch it or pick it up, which it dislike intensely. If it hears you coming, it will normally get out of the way as quickly as it can, but adders cannot move very rapidly and may attack before moving if you are very close. The effect of a bite varies considerably. It depends upon several things, one of which is the body-weight of the person bitten. The bigger the person, the less harmful the bite is likely to be, which is why children suffer far more seriously from snake bites than adults. A healthy person will also have better resistance against the poison. Very few people actually die from snake bites in Britain, and though these bites can make some people very ill, there are probably just as many cases of bites having little or no effect, as there are of serious illness.

单选题Accompanied by {{U}}cheerful{{/U}} music, we began to dance.

单选题Regular visits from a social worker can be of immense value to old people living alone.A. equalB. immediateC. moderateD. great

单选题It has been said that the Acts provided a new course of action and did not merely {{U}}regulate{{/U}} or enlarge an old one.

单选题He was not admitted to the club because he wasn"t a member.

单选题The astronomer was not interested in the way dolphins communicate with each other.

单选题The five classic foot positions in ballet are the basis for the {{U}}ethereal{{/U}} grace of the ballet dancer’s art.

单选题Airbus plans to build a mini-restaurant in the lower hold of A3XX.

单选题The two banks have announced plans to merge next year.A. closeB. sellC. breakD. combine

单选题The Spanish, French, Dutch, and English all vied for North American territory.

单选题Tim Lyons liked to play computer games in his spare time.

单选题It is obvious that there is difference in the way they view the matter.A. naturalB. certainC. inevitableD. clear

单选题Man cannot exit without water.A. expandB. riseC. liveD. quit

单选题The international finance policies always affect the flow of money among countries.A. appraisalB. numerationC. availabilityD. circulation

单选题暂缺

单选题The trains on the DLR are controlled by

单选题The architecture is {{U}}harmonious{{/U}} and no building is over six-storey high.

单选题In order to improve our standard of living, we have to accelerate production.A. step upB. decreaseC. stopD. control