未分类题

Weather Map
A weather map is an important tool for geographers. A succession of three of four maps presents a continuous picture of weather changes. Weather forecasts are able to determine the speed of air masses and fronts; to determine whether an individual pressure area is deepening or becoming shallow and whether a front is increasing or decreasing in intensity. They are also able to determine whether an air mass is retaining its original characteristics or taking on those of the surface over which it is moving. Thus, a most significant function of the map is to reveal a synoptic picture of conditions in the atmosphere at a given timE.
All students of geography should be able to interpret a weather map accurately. Weather maps contain an enormous amount of information about weather conditions existing at the time of observation over a large geographical areA.They reveal in a few minutes what otherwise would take hours to describE.The United States weather Bureau issues information about approaching storms, floods, frosts, droughts, and all climatic conditions in general. Twice a month it issues a 30-day 'outlook' which is a rough guide to weather conditions likely to occur over broad areas of the United States. These 30-day outlo6ks are based upon an analysis of the upper air levels with often Set the stage for the development of air masses, fronts, and storms.
Considerable effort is being exerted today to achieve more accurate weather predictions. With the use of electronic instruments and earth satellites, enormous gains have taken place recently in identifying and tracking storms over regions which have but few meteorological stations. Extensive experiments are also in progress for weather modification studies. But the limitations of weather modification have prevented meteorological results except in the seeding of super-cooled, upslope mountainous winds which have produced additional orographical precipitation on the windward side of mountain ranges. Nevertheless, they have provided a clearer understanding of the fundamentals of weather elements.
One characteristic of weather maps not mentioned by the author in this passage is______.
A.wind speed
B.thermal changes
C.fronts
D.barometric pressure

A.B.
C.
One
D.
A.wind
E.thermal
F.fronts
D.barometric

【参考答案】

B
解析：本文在第一段第二句中列举了从气象图上可以确定的信息，其中“the speed of air masse......

(↓↓↓ 点击下方‘点击查看答案’看完整答案 ↓↓↓)

<上一题目录下一题>

热门试题

未分类题

Differences of PolicemenReal policemen hardly recognize any resemblance between their lives and what they see on TV.The first difference is that a policeman's real life revolves round criminal law. He has to know exactly what actions are crimes and what evidence can be used to prove them in court. He has to know nearly as much law as a professional lawyer, and what is more, he has to apply it on his feet, in the dark and rain, running down a street after someone he wants to talk to.Little of his time is spent in chatting, he will spend most of his working life typing mil- lions of words on thousands of forms about hundreds of sad, unimportant people who are guilty of stupid, petty crimes.Most television crime drama is about finding the criminal: as soon as he's arrested, the story is over. In real life, finding criminals is seldom much of a problem. Except in very serious cases like murders and terrorist attacks little effort is spent on searching.Having made an arrest, a detective really starts to work. He has to prove his case in court and to do that he often has to gather a lot of difference evidencE.At third big difference between the drama detective and the real one is the unpleasant pressures: first, as members of a police force they always have to behave absolutely in accordance with the law; secondly, as expensive public servants they have to get results. They can hardly ever do both. Most of the time some of them have to break the rules in small ways.If the detective has to deceive the world, the world often deceives him. Hardly anyone he meets tells him the truth. And this separation the detective feels between himself and the rest of the world is deepened by the simple-mindedness—as he sees it—of citizens, social workers, doctors, law-makers, and judges, who, instead of eliminating crime punish the criminals less severely in the hope that this will make them reform. The result, detectives feel, is that nine tenths of their work is recatching people who should have stayed behind bars. This makes them rather cynical.A policeman has to be trained in criminal law because______.A.he must be able to tell when and where a crime is committedB.he must justify the arrests he makes of criminalsC.he must behave as professional lawyers doD.he must work hard to help reform. criminals

A.B.
C.
D.
E.
F.
G.
A
H.
A.he
I.he
J.he
K.he

未分类题

In the eighteenth century, Japan's feudal overlords, from the shogun to the humblest samurai, found themselves under financial stress. In part, this stress can be attributed to the overlords' failure to adjust to a rapidly expanding economy, but the stress was also due to factors beyond the overlords' control. Concentration of the samurai in castle towns had acted as a stimulus to nudE.Commercial efficiency, in turn, had put temptations in the way of buyers. Since most samurai had been reduced to idleness by years of peace, encouraged to engage in scholarship and martial exercises or to perform. administrative tasks that took little time, it is not surprising that their tastes and habits grew expensivE.Overlords' income, despite the increase in rice production among their tenant farmers, failed to keep pace with their expenses. Although shortfalls in overloads' income resulted almost as much from laxity among their tax collectors (the nearly inevitable outcome of hereditary office-holding) as from their higher standards of living, a misfortune like a fire or flood, bringing an in crease in expenses or a drop in revenue, could put a domain in debt to the city rice-brokers who handled its finances. Once in debt, neither the individual samurai nor the shogun himself found it easy to recover.It was difficult for individual samurai overlords to increase their income because the amount of rice that farmers could be made to pay in taxes was not unlimited, and since the income of Japan's central government consisted in part of taxes collected by the shogun from his huge domain, the government too was constraineD.Therefore, the Tokugawa shoguns began to look to other sources for revenuE.Cash profits from government-owned mines were already on the decline because the most easily worked deposits of silver and gold had been exhausted, although debasement of the coinage had compensated for the loss. Opening up new farmland was a possibility, but most of what was suitable had already been exploited and further reclamation was technically unfeasiblE.Direct taxation of the samurai themselves would be politically dangerous. This left the shoguns only commerce as a potential source of government incomE.Most of the country's wealth, or so it seemed, was finding its way into the hands of city merchants. It appeared reasonable that they should contribute part of that revenue to ease the shogun's burden of financing the statE.A means of obtaining such revenue was soon found by levying forced loans, known as goyo-kin; although these were not taxes in the strict sense, since they were irregular in timing and arbitrary in amount, they were high in yielD.Unfortunately, they pushed up prices. Thus, regrettably, the Tokugawa shoguns' search for solvency for the government made it increasingly difficult for individual Japanese who lived on fixed stipends to make ends meet.Which is the author's attitude toward the samurai discussed in the first paragraph?A.Warmly approving.B.Mildly sympathetiC.C.Bitterly disappointeD.D.Harshly disdainful.

A.B.
C.
Which
D.Warmly
E.
B.Mildly
F.
C.Bitterly
G.
D.Harshly