2002年6月英语四级 – 阅读理解C

It is hard to track the blue whale, the ocean’s largest creature, which has almost been killed off by commercial whaling and is now listed as an endangered species. Attaching radio devices to it is difficult, and visual sightings are too unreliable to give real insight into its behavior.
蓝鲸是海洋中最大的生物，商业捕鲸几乎将其灭绝，目前已被列为濒危物种。将无线电设备连接到它身上很困难，而且视觉观察太不可靠，无法真正了解它的行为。

So biologists were delighted early this year when, with the help of the Navy, they were able to track a particular blue whale for 43 days, monitoring its sounds. This was possible because of the Navy’s formerly top-secret system of underwater listening devices spanning the oceans.
因此，今年年初，生物学家们很兴奋，在海军的帮助下他们追踪了一头特定的蓝鲸43天，监测它的声音。这是可能的，因为海军以前的绝密系统是横跨海洋的水下监听设备。

Tracking whales is but one example of an exciting new world just opening to civilian scientists after the cold war as the Navy starts to share and partly uncover its global network of underwater listening system built over the decades to track the ships of potential enemies.
追踪鲸鱼只是一个令人兴奋的新世界的例子，这个新世界在冷战后刚刚向平民科学家开放，因为海军开始分享并部分揭开其几十年来为追踪潜在敌人的船只而建立的全球水下监听系统网络。

Earth scientists announced at a news conference recently that they had used the system for closely monitoring a deep-sea volcanic eruption for the first time and that they plan similar studies.
地球科学家在最近的新闻发布会上宣布，他们首次使用该系统密切监测深海火山喷发，并计划进行类似的研究。

Other scientists have proposed to use the network for tracking ocean currents and measuring changes in ocean and global temperatures.
其他科学家提议使用该网络来跟踪洋流，测量海洋和全球温度的变化。

The speed of sound in water is roughly one mile a second—slower than through land but faster than through air. What is most important, different layers of ocean water can act as channels for sounds, focusing them in the same way a stethoscope does when it carries faint noises from a patient’s chest to a doctor’s ear. This focusing is the main reason that even relatively weak sounds in the ocean, especially low-frequency ones, can often travel thousands of miles.
声音在水中的速度大约是每秒一英里——比陆地慢，但比空气快。最重要的是，不同的海水层可以充当声音的通道，就像听诊器将微弱的声音从患者的胸部传给医生的耳朵一样聚焦声音。海洋中即使是相对较弱的声音，尤其是低频声音，因为聚焦也能传播数千英里。