手机APP下载

您现在的位置: 首页 > 在线广播 > 科学美国人 > 科学美国人地球系列 > 正文

科学美国人60秒:飞奔的冰川

来源:可可英语 编辑:aimee   可可英语APP下载 |  可可官方微信:ikekenet
 下载MP3到电脑  批量下载MP3和LRC到手机
加载中..
bq7zEyFM&I,~9ZhXUdMu

yOf%YIcp=0~W&fqXQye

Hi, I'm Scientific American podcast editor Steve Mirsky. And here's a short piece from the April issue of the magazine, in the section we call Advances: Dispatches from the Frontiers of Science, Technology and Medicine:
Glacial Sprint by Katherine Kornei
Most glaciers creep along at a pace that is, well, glacial. But one in northern Pakistan breaks into a gallop with astounding speed and regularity: Khurdopin glacier "surges" every two decades, moving roughly 1,500 times its normal pace. This sends ice tumbling into a nearby river, damming it to create a temporary lake that can suddenly inundate nearby villages. Now scientists in Europe have used new high-resolution satellite data to study Khurdopin before and during its most recent surge in 2017, revealing how the event developed on a near daily basis, in unprecedented detail. The observations are critical to monitoring the glacier's hazards and could help to predict when flooding might occur next.
About 1 percent of the world's glaciers exhibit such sudden and large bursts of speed. Jakob Steiner, a geoscientist at Utrecht University in the Netherlands, who led the study said, "It's not 100 percent clear why some glaciers surge and others don't." Some scientists think water permeates a glacier's base and acts as a lubricant to promote sliding. Sediments between a glacier and the ground may also facilitate slippage.

4.~Mh1jt8vf)F3djw+

冰川.jpg
Steiner and his team analyzed new satellite images of Khurdopin that revealed features as small as three meters across. As snow accumulated on the high-elevation end of the 41-kilometer river of ice, the crushing pressure changed the structure of the water molecules, causing the ice to melt at lower temperatures and allowing the mass to suddenly shift. Khurdopin surged up to 20 meters a day in May 2017, creating a lake that grew to 30 times its size before draining and washing away roads, bridges and farmland, the scientists reported in January in The Cryosphere.
Steiner and his colleagues plan to return to Pakistan this year to continue installing temperature and rain sensors around Khurdopin and training area residents to monitor the glacier and its transient lake.
That was Glacial Sprint by Katherine Kornei.

2ObBZUuWG2&U8Zu

e,zGpu#f_.~!.pRzj

vIl03KFS0X20F3Nv0s0tZNCT[zWuGnaFGvqkK#TM^VbR

重点单词   查看全部解释    
regularity [.regju'læriti]

想一想再看

n. 规律性,规则性,匀整,定期

 
temperature ['tempritʃə(r)]

想一想再看

n. 温度,气温,体温,发烧

 
transient ['trænʃənt,'trænziənt]

想一想再看

adj. 短暂的
n. 短期居留者,瞬间的变化

联想记忆
slippage ['slipidʒ]

想一想再看

n. 滑移;滑动;下降

联想记忆
promote [prə'məut]

想一想再看

vt. 促进,提升,升迁; 发起; 促销

联想记忆
unprecedented [ʌn'presidəntid]

想一想再看

adj. 空前的,前所未有的

联想记忆
glacial ['gleisiəl]

想一想再看

adj. 冰的,冰川(期)的,非常冷的,缓慢的

联想记忆
exhibit [ig'zibit]

想一想再看

v. 陈列,展览,展示
n. 展品,展览

联想记忆
pressure ['preʃə]

想一想再看

n. 压力,压强,压迫
v. 施压

联想记忆
critical ['kritikəl]

想一想再看

adj. 批评的,决定性的,危险的,挑剔的
a

 

发布评论我来说2句

    最新文章

    可可英语官方微信(微信号:ikekenet)

    每天向大家推送短小精悍的英语学习资料.

    添加方式1.扫描上方可可官方微信二维码。
    添加方式2.搜索微信号ikekenet添加即可。