雅思真题听力场景精练 第57期:科技类讲座 地质与考古(6)
日期:2013-07-21 16:00

(单词翻译:单击)

Okay, now for some practicalities. What do geographers actually do? Well, we collect data to begin with. You’ll be doing a lot of that on your first field trio! How do we do this? There are several means. We might, for example, conduct a census——court a population in a given area perhaps. We also need images of the earth’s surface which we can produce by means of computer-generation technology or with the help of satellite relays. We’ve come a very long way from the early exploration of the world by sailing ships when geographers only had pens and paper at their disposal.

After we’ve gathered information, we must analyze it! We need to look for patterns, most commonly those of causes and consequences. This kind of information helps us to predict and resolve problems that could affect the world we live in. But we don’t keep all these information confidential. We then need to publish our findings so that other people can access it and be informed by it. And one way in which this information can be published is in the form of maps. You’ll all have used one at some stage of your life already. Let’s consider the benefits of maps from a geographer’s perspective.

Maps can be folded and put in a pocket and can provide a great store of reference when they’re collected into an atlas. They can depict the physical features of the entire planet if necessary, or just a small part of it in much greater detail. But there is a drawback. You can’t exactly replicate something that is three-dimensional, like our planet, on a flat piece of paper, because paper has only two dimensions, and that means there’ll always be a certain degree of distortion on a map. It can’t be avoided.

We can also use aerial photographers...pictures taken by cameras at high altitude above the earth. These are great for showing all kinds of geographical features that are not easy to see from the ground. You can easily illustrate areas of diseased trees or how much traffic is on the roads at a given time or information about deep sea beds, for example.

Then there are Landsats. These are satellites that circle the earth and transmit visual information to computers at receiving stations. They circle the earth several times a day and can provide a mass of information——you’ll all be familiar with the information they give us about the weather, for example.

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重点单词
  • informedadj. 见多识广的 v. 通告,告发 vbl. 通告,
  • producen. 产品,农作物 vt. 生产,提出,引起,分娩,制片
  • affectvt. 影响,作用,感动
  • collectv. 收集,聚集 v. 推论 adv. 接收者付款
  • resolven. 决定之事,决心,坚决 vt. 决定,解决,分离,表
  • depictvt. 描述,描绘
  • certainadj. 确定的,必然的,特定的 pron. 某几个,某
  • perspectiven. 远景,看法,透视 adj. 透视的
  • distortionn. 扭曲,变形,曲解
  • predictv. 预知,预言,预报,预测