首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
A、It provides valuable evidence for climate research. B、It offers advice on crossing the Sahara Desert. C、It helps predict when
A、It provides valuable evidence for climate research. B、It offers advice on crossing the Sahara Desert. C、It helps predict when
admin
2022-08-21
52
问题
A new study suggests climate conditions in the Sahara Desert have changed from wet to dry about every 20000 years. The study was carried out by scientists at America’s Massachusetts Institute of Technology, or MIT. Findings were published in the journal Science Advances. The research was partly funded by the National Science Foundation.
The Sahara Desert is known as one of the hottest, driest and most desolate areas in the world. But previous evidence has suggested the Sahara did not always experience such extreme heat and dry conditions. The evidence included material collected from fossils and rock paintings from the area. The evidence showed that at times, the Sahara changed to a very wet climate. This permitted plants and animals to develop and grow and led to the creation of human settlements. Now, researchers have discovered more evidence of this changing climate. The scientists examined dust gathered from the coast of West Africa over the past 240000 years. The research showed that during that period, the Sahara’s climate kept changing between wet and dry about every 20000 years.
David McGee is an associate professor in MIT’s Department of Earth, Atmospheric and Planetary Sciences. He helped lead the study. McGee said the new evidence supports the idea that the area’s climate repeatedly kept changing over the years. " Our results suggest the story of North African climate is dominantly this 20000-year beat, going back and forth between a green and dry Sahara, " he said. McGee and other researchers reported these back and forth climate changes were mainly driven by changes in the Earth’s axis as the planet orbits the sun. This process affects the amount of sunlight between seasons. The research suggests that every 20000 years, the Earth receives more intense summer sunlight. When the Earth’s axis changes again, the amount of sunlight is reduced. This season change happened continuously every 20000 years, the study found. The other part of the season produced monsoon conditions, resulting in a wetter, greener, plant-rich environment. When the rainy activity weakens, the climate becomes hot and dry, like the Sahara remains today. The scientists based their research on dust samples collected from ocean sediment. McGee says he thinks the latest research can be valuable in studying the Sahara’s history as it relates to human settlement. "What times could have been good for humans to settle the Sahara Desert and cross it to disperse out of Africa, versus times that would be inhospitable like today, " he said.
Questions 19 to 22 are based on the recording you have just heard.
19. What does the new MIT research find about the Sahara Desert?
20. What was the previous evidence showing that the Sahara did not always experience extre conditions?
21. What caused the climate changes in the Sahara Desert?
22. Why does McGee believe that the latest research is valuable?
选项
A、It provides valuable evidence for climate research.
B、It offers advice on crossing the Sahara Desert.
C、It helps predict when the Sahara Desert will become wet.
D、It relates to human settlement in the Sahara Desert.
答案
D
解析
由原文可知,McGee认为最新的研究对于研究撒哈拉沙漠的历史很有价值,因为它与人类定居有关。因此答案为D。
转载请注明原文地址:https://kaotiyun.com/show/DOx7777K
0
大学英语六级
相关试题推荐
A、ItteachestheforeignchildrenEnglish.B、Itteachesthechildrenforeignlanguages.C、Ittrainstheteachersforforeignlan
A、Playingwithparents.B、Talkingwithothers.C、Playingcardswithothers.D、Drawingandmakingthings.D
A、Theyaredelightedbecausetheycanenjoythescenerywhiledriving.B、Theyarefrightenedbecausetrafficaccidentsarefrequ
A、Becauseitrequiresmoretimethanpassingalaw.B、Becauseitcannotreduceunemploymentrate.C、Becauseitoffendsthebenef
A、Childrencanlearnhowabusinessworksinsociallife.B、Childrenmayunderstandwhatanormalfamilylifeis.C、Childrenmay
A、Watermightbecomecleanandpure.B、Peoplewillliveinabetterenvironment.C、Therewillbenopolicetoprotectpeople.D、
A、Anestimateddateofdeliveryisgenerallyinaccurate.B、Anestimateddateofdeliveryisratheraccurate.C、Anestimateddate
A、Bitcoinsareusedanonymously,B、Bitcoinsarethebestregulated.C、Lesstaxesareimposedonbitcoins.D、Itismoreconvenien
A、Cooperationandconcession.B、Equalityandmutualbenefit.C、Exchangingdailynecessities.D、Introducingadvancedtechnology.
A、Toregulatetheirbodytemperature.B、Tocatchjellyfishatthewarmersurface.C、Tolayeggsatthewarmersurface.D、Totake
随机试题
患儿3岁4个月,一直没有接受过康复训练。反应一般,言语少,自主进食。能独坐、翻身,不能独站,四肢肌张力痉挛Ⅱ级,跟腱明显挛缩,尖足内翻,扶持行走时有剪刀步。患儿目前主要的治疗方法不宜选用
本质上说,语言的发展是一个自我筛选、自我调适、自我更新、角我净化的过程。一味地拒绝排斥并不是“保卫汉语、纯洁汉语”,自我封闭只会导致汉语逐渐失去生命力。语言最重要的功能是交流,不要赋予其太多的意识形态功能,更不能将“收录字母词”夸大为“从根本上破坏中国文化
根据全国人民代表大会组织法的规定,下列哪些机构或人员可以提出对于全国人民代表大会常务委员会的组成人员,中华人民共和国主席、副主席,国务院和中央军事委员会的组成人员,最高人民法院院长和最高人民检察院检察长的罢免案?()
质量保修书的主要内容包括( )。
企业对股票、短期债券和长期债券进行投资,共同的目的是()。
资本市场中的初级市场即______市场。
下列各句中,标点符号使用规范的一句是()。
在维果斯基的文化历史理论中涉及的概念有()。
使用VC++2010打开考生文件夹下prog1中的解决方案。此解决方案的项目中包含一个源程序文件prog1.c。在此程序中,请编写一个函数,用来删除字符串中的所有空格。例如,输入asdafaaz67,则输出为asdafaaz67。注意:部分源程序
WhenIwasyoung,Ispentmysummervacationsonmygrandparents’farm.ThesummerthatIgraduatedfromcollege,I【C1】______my
最新回复
(
0
)