首页
登录
职称英语
If pollution continues to increase at the present rate, formation of aerosol
If pollution continues to increase at the present rate, formation of aerosol
游客
2023-09-11
53
管理
问题
If pollution continues to increase at the present rate, formation of aerosols (悬浮微粒) in the atmosphere will cause the onset (开始) of an ice age in about fifty years’ time. This conclusion, reached by Dr. S. Rasool and Dr. H. Schneider of the United States Goddard Space Flight Centre, answers the apparently conflicting questions of whether an increase in the carbon dioxide content of the atmosphere will cause the Earth to warm up or increasing the aerosol content will cause it to cool down. The Americans have shown conclusively that the aerosol question is dominant.
Two specters haunting conservationists have been the prospect that environmental pollution might lead to the planet’s becoming unbearably hot or cold. One of these ghosts has now been laid, because it seems that even an increase in the amount of carbon dioxide in the atmosphere to eight times its present value will produce an increase in temperature of only 2℃. which would take place over several thousand years. But the other problem now looms larger than ever.
Aerosols are collections of small liquid or solid particles dispersed in air or some other medium. The particles are all so tiny that each is composed of only a few hundred atoms. Because of this they can float in the air for a very long time. Perhaps the most commonly experienced aerosol is industrial smog of the kind that plagued London in the 1950s and is an even greater problem in Los Angeles today. These collections of aerosols reflect the Sun’s heat and thereby cause the Earth to cool.
Dr. Rasool and Dr. Schneider have calculated the exact effect of a dust aerosol layer just above the Earth’s surface in the temperature of the planet. As the layer builds up, the present delicate balance between the amount of heat absorbed from the Sun and the amount radiated from the Earth is disturbed. The aerosol layer not only reflects much of the Sun’s light but also transmits the infrared radiation from below. So, while the heat input to the surface drops, the loss of heat remains high until the planet cools to a new balanced state.
Within fifty years, if no steps are taken to stop the spread of aerosols in the atmosphere, a cooling of the Earth by as much as 3.5℃ seems inevitable. If that lasts for only a few years it would start another ice age, and because the growing ice caps at each pole would themselves reflect much of the Sun’s radiation it would probably continue to develop even if the aerosol layer were destroyed.
The only bright spot in this gloomy forecast lies in the hope expressed by Dr. Rasool and Dr. Schneider that nuclear power may replace fossil fuels in time to prevent the aerosol content of the atmosphere from becoming critical. [br] The author’s main purpose in writing the article is to warn of ______.
选项
A、warm weather
B、hot weather
C、a new ice age
D、a new iceberg
答案
C
解析
主旨题。根据第一段第一句,如果污染继续按目前的速度持续增加,大气中的悬浮颗粒将在大约50年内导致冰川时代的到来。
转载请注明原文地址:https://tihaiku.com/zcyy/3003860.html
相关试题推荐
Theresultofautomationmaywellbeanincreaseinemployment,sinceitis
Theresultofautomationmaywellbeanincreaseinemployment,sinceitis
Theresultofautomationmaywellbeanincreaseinemployment,sinceitis
Theresultofautomationmaywellbeanincreaseinemployment,sinceitis
Theresultofautomationmaywellbeanincreaseinemployment,sinceitis
Theresultofautomationmaywellbeanincreaseinemployment,sinceitis
[originaltext]W:Hi,Bob.Haveyougivenyouroralpresentationperformancein
[originaltext]W:Hi,Bob.Haveyougivenyouroralpresentationperformancein
Aftermorethan40yearsofparalleldevelopment,theinformationandlife
Aftermorethan40yearsofparalleldevelopment,theinformationandlife
随机试题
Manyayoungpersontellsmehewantstobeawriter.Ialwaysencouragesu
Thispartistotestyourabilitytodopracticalwriting.Youarerequir
Thereisno【B1】______thatstudentsshouldlearnsomethingabouthowcomputer
下列有关移动平均法的说法中,正确的是()。A.应用移动平均法的关键在于步长的选
关于个人所得税的股票转让的纳税问题,描述不正确的有( )。 Ⅰ.王某转让持有
每一个生产者或消费者都只是被动地接受市场价格,他们对市场价格没有任何控制力量的市
使红细胞沉降率加快的因素有A.血浆中白蛋白增多 B.血浆中球蛋白增多 C.血
关于拐卖妇女、儿童罪的认定,下列哪些选项是正确的?()A.以出卖为目的,对婴幼
与债券的信用等级有关的利率因素是( )。A.纯利率 B.违约风险溢价 C.
在双代号网络图中,虚箭线的作用有( )。(2015真题)A.指向 B.
最新回复
(
0
)