首页
登录
职称英语
One fine day about 74,000 years ago, a giant volcano on Sumatra blew its top
One fine day about 74,000 years ago, a giant volcano on Sumatra blew its top
游客
2024-01-20
27
管理
问题
One fine day about 74,000 years ago, a giant volcano on Sumatra blew its top. The volcano, named Toba, may have ejected (喷射) 1,000 times more rock and other material than Mount St. Helens in Washington state did in 1980. In the process, it cooled the climate by at least 10°C, causing a global famine.
Paleoclimate (古气候) evidence suggests that the Toba eruption, which occurred during the last ice age, emitted lots of sulfur dioxide—vastly more than Mount St. Helens did. The eruption also coincided with the start of a 1,000-year period of even colder temperatures. Some scientists have suggested that Toba caused the deep freeze and that perhaps such an event happening today could bring on a new ice age. But models developed by National Aeronautics and Space Administration and the National Center for Atmospheric Research in Boulder, Colorado, argue otherwise.
Researchers led by climatologist Alan Robock of Rutgers University in New Brunswick, New Jersey, ran scenarios that featured eruptions producing up to several times more sulfur dioxide than
Toba. The result, published 27 May in the Journal of Geophysical Research: Atmospheres, was a cooler climate that lasted only a few decades. So the 1,000-year cold spell was probably part of the natural cycle that has produced more than a dozen ice ages over the past couple of million years.
"The results virtually eliminate mega (非常大的) volcanic eruptions as one of the key drivers of global-scale glaciation," says climatologist Ellen Mosley-Thompson of Ohio State University in Columbus, who was not involved in the study. So, paleoclimatologists should focus on more likely climate coolers, she says, such as changes in ocean circulation or cyclical variations in Earth’s orbit around the sun.
Still, if Toba erupted today like it did in the past, the results would be catastrophic. Although the volcano isn’t expected to blow its top for thousands of years, Robock and colleagues estimate a mega eruption could lower global temperatures by as much as 17°C for several years, followed by a recovery to normal conditions that could take decades. That would hit the human population with the double whammy of dramatically reduced agricultural production and widespread loss of vegetation, leading to widespread food shortages and starvation. [br] What can be learned about the time of the Toba eruption?
选项
A、The eruption coincided with the end of the last ice age.
B、A new ice age triggered off the Toba eruption.
C、The eruption occurred when the Earth was at its coldest time.
D、The eruption happened when a 1,000-year period of colder temperatures began.
答案
D
解析
由题干中的the time of the Toba eruption定位到第二段第二句。细节辨认题。由定位句可知,多巴火山的爆发时间也恰巧是千年寒冷期的开端,因此D)为正确答案。
转载请注明原文地址:https://tihaiku.com/zcyy/3380184.html
相关试题推荐
[originaltext]MountEtnaisoneofthemostactivevolcanoesonEarth.Themoun
[originaltext]MountEtnaisoneofthemostactivevolcanoesonEarth.Themoun
[originaltext]MountEtnaisoneofthemostactivevolcanoesonEarth.Themoun
[originaltext]Thousandsofpeoplelivinginvillagesclosesttothevolcano
[originaltext]Thousandsofpeoplelivinginvillagesclosesttothevolcano
Onefinedayabout74,000yearsago,agiantvolcanoonSumatrablewitstop
Onefinedayabout74,000yearsago,agiantvolcanoonSumatrablewitstop
Onefinedayabout74,000yearsago,agiantvolcanoonSumatrablewitstop
Onefinedayabout74,000yearsago,agiantvolcanoonSumatrablewitstop
Onefinedayabout74,000yearsago,agiantvolcanoonSumatrablewitstop
随机试题
Thetroublewithtelevisionisthatitdiscouragesconcentration.Television
AtthefirstsighttheplanetMars(火星)doesnotappearverywelcometoanyki
______canmakeanimmensecontributiontothecreationofpeaceandplentyint
PartTimeTransporterHertzLocalEditionisseekin
Youshouldspendabout20minutesonQuestions27-40,whicharebasedonReading
Moreartificialreefs(礁石)arebeingloweredintotheoceannowthaneverbefo
按照随机模型,确定现金存量的下限时,应考虑的因素有()。A.企业每日最低现金需要
鉴定曲霉常用的培养基是A:察氏琼脂B:尿素琼脂C:脑心葡萄糖血琼脂D:酵母
以下不属于银团参加行的主要职责的是()。A.参加银团会议 B.按照约定及时足额
先天性心脏病室间隔缺损A.心尖部抬举性搏动 B.心前区收缩期搏动 C.心底部
最新回复
(
0
)