Question

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 43 to 50.

Many of the most damaging and life-threating types of weather-torrential rains, severe thunderstorms, and tornadoes-begin quickly, strike suddenly, and dissipate rapidly, devastating small regions while leaving neighboring areas untouched. One such event, a tornado, struck the northeastern section of Edmonton, Alberta, in July 1987. Total damages from the tornado exceeded $250 million, the highest ever for any Canadian storm. Conventional computer models of the atmosphere have limited value in predicting short-live local storms like the Edmonton tornado, because the available weather data are generally not detailed enough to allow computers to discern the subtle atmospheric changes that precede these storms. In most nations, for example, weather balloon observations are taken just once every twelve hours at locations typically separated by hundreds of miles. With such limited data, conventional forecasting models do a much better job predicting general weather conditions over large regions than they do forecasting specific local events.

Until recently, the observation-intensive approach needed for accurate, very short range forecasts, or “Nowcasts”, was not feasible. The cost of equipping and operating many thousands of conventional weather stations was prohibitively high, and the difficulties involved in rapidly collecting and processing the raw weather data from such a network were insurmountable. Fortunately, scientific and technological advances have overcome most of these problems. Radar systems, automated weather instruments, and satellites are all capable of making detailed, nearly continuous observation over large regions at a relatively low cost. Communications satellites can transmit data around the world cheaply and instantaneously, and modern computers can quickly compile and analyzing this large volume of weather information. Meteorologists and computer scientists now work together to design computer programs and video equipment capable of transforming raw weather data into words, symbols, and vivid graphic displays that forecasters can interpret easily and quickly. As meteorologists have begun using these new technologies in weather forecasting offices, Nowcasting is becoming a reality.

Question 46: Why does the author state that observations are taken “just once every twelve hours”?

A. To indicate that the observations are timely

B. To show Why the observations are of limited value

C. To compare data from balloons and computers

D. To give an example of international cooperation

Answer 1

Đáp án B

Dịch nghĩa: Tại sao tác giả lại khẳng định rằng những quan sát được thực hiện “chi một lần vào mỗi 12 giờ”?

A. Để chỉ ra rằng sự quan sát rất đúng giờ.

B. Để giải thích tại sao sự quan sát có giá trị giới hạn.

C. Để so sánh số liệu từ khinh khí cầu và máy tính.

D. Đế cho ví dụ về sự hợp tác quốc tế.

Giải thích: Trong đoạn 1 có nói rằng: “the available weather data are generally not detailed enough to allow computers to discern the subtle atmospheric changes... In most nations, for example, weather balloon observations are taken just once every twelve hours at locations typically separated by hundreds of miles” - “số liệu thời tiết sẵn có thường không đủ chi tiết để cho phép máy tính phân biệt những thay đổi thời tiết phức tạp... Ở hầu hết các quốc gia, ví dụ, quan sát từ khinh khí cầu chỉ được thực hiện một lần mỗi 12 giờ đồng hồ ớ những địa điểm bị chia cách bởi hàng trăm dặm”

=> Như vậy có thể hiểu dữ liệu mang lại từ quan sát truyền thống không đủ giá trị để dự báo chính xác.