首页
登录
职称英语
Listening out for whale song is one way that ships can avoid colliding with
Listening out for whale song is one way that ships can avoid colliding with
游客
2025-04-25
43
管理
问题
Listening out for whale song is one way that ships can avoid colliding with whales. But what do you do if the whales aren’t singing? One answer, developed by researchers in the Canary Islands, is to focus on the way the giant creatures mask the clamour of ocean noise.
No one knows how many whales are killed by ships each year, but collisions are thought to ac- count for up to a third of unnatural deaths. For the northern right whale, this means one or two individuals every year, and with only 300 animals left, that’s an unacceptable loss. There are three global hot spots for whale collisions: northern right whales are at risk in the Atlantic off the east coast of the US and Canada, fin whales in the Mediterranean, and sperm whales off the Canary Islands.
Last year, the Massachusetts-based international Fund for Animal Welfare attached hydro- phones to buoys and successfully listened out for right whale song in the North Atlantic. But since right whales remain silent for hours at a time, and sperm whales are silent for around haft the time, a better tracking technology is needed.
The new Whale Anti-Collision System (WACS), developed by Michel Andre, is designed to help ships in these hot spots steer clear of the whales. It uses a sonar technique called ambient noise imaging to locate the animals even when they are silent.
To do this, Andre has been testing a long lines of buoys, each bristling with 32 sensitive under- water microphones, or hydrophones, that pick up sea sounds such as breaking waves, rain and ship- ping noise. Any approaching whale blocks this background noise and creates a detectable "sound shadow".
By comparing the reflections received from the hydrophones on different buoys, Andre’s system can gather enough information to work out the whale’ s position and how fast it is moving. Software displays the results, on a 3D colour map. Underwater objects stand out like hot spots on a thermal image. In trials planned for next year, Andre will place two lines of 12 spherical buoys along the 120-kilometre ferry route between the islands of Tenerife and Gran Canaria. The signals will be sent to a land station where they will be analysed to create a 3D picture of the sea in real time.
If the trials are successful, the WACS software could be installed aboard ferries so that ships’ masters can steer clear of whales. Failing that, the whales’ movements could be tracked from shore- based installation and radioed to ships in the area. [br] The loss of one or two northern fight whales every year is considered an unaeeeptable loss because they ______.
选项
A、are the only Whales that can sing songs
B、are the only whales capable of masking the clamour of ocean noise
C、provide clues to scientists to study sea currents and waves
D、are on the very verge of distinction
答案
D
解析
从文中第二段可知with only 300 animals (northern right whales) left,如果每年减少一两头,该鲸群不久就会灭绝,选项D正确。
转载请注明原文地址:https://tihaiku.com/zcyy/4052904.html
相关试题推荐
Withhumanfootprintsonthemoon,radiotelescopeslisteningformessagesf
Listeningoutforwhalesongisonewaythatshipscanavoidcollidingwith
Listeningoutforwhalesongisonewaythatshipscanavoidcollidingwith
Listeningoutforwhalesongisonewaythatshipscanavoidcollidingwith
Listeningoutforwhalesongisonewaythatshipscanavoidcollidingwith
It’srainingagain.AsIlieawakeinbed,listeningtothesoundofthoserazor
Iwas(ontheverge)of(incurring)Mr.Rochester’swrathbynotlisteningtohi
Withhumanfootprintsonthemoon,radiotelescopeslisteningformessagesfr
Withhumanfootprintsonthemoon,radiotelescopeslisteningformessagesfr
Withhumanfootprintsonthemoon,radiotelescopeslisteningformessagesfr
随机试题
Youshouldspendabout20minutesonthistask.Thebarchartbelowshowsthenu
Oneofthegoodthingsformeninwomen’sliberationisthatmennolongerh
Thewaythatpeoplespendtheirmoney,andtheobjectsonwhichtheyspend
Inthissection,youwillhearashortpassage.Thereare10missingwordsorph
WhohasalowerriskofdevelopingAlzheimer’sdisease?A、Peoplewhohavereceive
用户可以使用()向DHCP服务器重新请求IP地址配置。A、ipconfig/
环境污染产生的急性危害中不包括A.地方性氟中毒 B.印度博帕尔发生的异氰基甲酯
下列属于高耗能行业的是:() A.电子信息 B.电力、热力的生产和供应业
从房地产市场整体出发,分析开发和销售之间的数量结构关系,考察房地产供给和需求之间
一般来说线上影线越长,下影线越短,阴线实体越短,越表明多方占一定优势。()
最新回复
(
0
)