文章大意:本文是一篇说明文。人工云技术可能很快就会用于对抗环境破坏。澳大利亚的研究人员使用机器向空气中喷洒盐水,并指出这些人工云的反射特性有助于保护大堡礁免受太阳白化。文章介绍人工云技术带来的好处。
Artificial cloud technology could soon be used in the fight against environmental damage. Researchers in Australia have used machines to spray salt water into the air, and noted that the reflective qualities of these artificial clouds helped protect the Great Barrier Reef from sun bleaching (漂白).
The so-called cloud brightening project works by thickening existing clouds and reducing sunlight exposure to protect the reef. No artificial chemicals make it into the clouds in the sky. When water droplets steam, they leave only small salt crystals that float up into the atmosphere. This provides a larger surface area for water vapor to be liquids around them, forming thicker clouds.
The past two years have seen uncommon forest fires and droughts triggered by the climate change emergency, meaning that widespread use of this technique may become more commonplace if carbon emissions are not checked.
Drones, unmanned flying vehicles, have also entered the cloud controlling picture, used in the United Arab Emirates, a country desperately in need of more rainfall, to deliver electrical shocks to clouds in order to facilitate rainfall. Zapping (击打) clouds to produce a positive or negative charge within clouds can cause water droplets to form together. The greater the charge, the larger the droplets, which is vital for ensuring that as much rain as possible reaches the surface before steam gives off all the hard-won moisture (水分).
Even if one waves aside climate change, global waterfall shortages are still an increasing concern, given the planet’s booming population. More people means more mouths to feed, and the demand for water in agriculture for animals and crops further increases urgency for cloud controlling technology. An increase in rain also leads to positive economic growth in many countries, as large harvests stabilize financial systems and living standards in all climates.
Increasingly, scientists are looking to our skies in providing solutions to protect our environment. Cloud controlling technologies have promise. However, for this field of science to become practical economically, more research needs to be done in making this process a practicable option in protecting our environment.
12. How does the cloud brightening project work?
A.By creating more water vapor which later becomes liquids. |
B.By spraying chemicals and small salt crystals into the atmosphere. |
C.By expanding the water vapor arca and blocking more sunlight. |
D.By steaming water droplets to provide a larger surface area. |
13. What do we know about drones from paragraph 4?
A.They spread larger water droplets. |
B.They charge clouds to promote rain. |
C.They will be popularized in dry years. |
D.They control the movements of clouds. |
14. What is paragraph 5 mainly about?
A.Problems of overpopulation. |
B.Solutions to waterfall shortage. |
C.Urgency of economic development. |
D.Additional benefit of cloud technology. |
15. Which aspect does the author think should be improved?
A.High cost. |
B.Research method. |
C.Environmental impact. |
D.Complicated process. |