1 . 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.
1. 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. |
| 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. |
| A．Problems of overpopulation. |
| B．Solutions to waterfall shortage. |
| C．Urgency of economic development. |
| D．Additional benefit of cloud technology. |
| A．High cost. |
| B．Research method. |
| C．Environmental impact. |
| D．Complicated process. |
2 . Help Hermit Crabs
Hermit crabs are nature’s recyclers. They eat waste and help keep oceans and shores clean. Unlike other crabs, the hermit crab has a thin outer shell over its soft tail. This makes the hermit crab easy prey for hungry predators. Hermit crabs stay safe by living in old seashells. A hermit crab is picky; it tries on many shells until it finds one that fits just right. In recent years, however, many hermit crabs have had trouble finding their perfect homes. What is the problems There are not enough shells to go around!
One reason for the seashell shortage is that ocean water is not as clean as it once was. This has caused chemical changes to sea water. Some sea animals, like snails, are affected by these changes. Now there are fewer snails making shells. People visiting the beach often take shells home as souvenirs. This is another problem. Other people even take shells for their own pet hermit crabs! They do not realize that hermit crabs in the wild need those shells too.
Now people are working to solve this hermit crab housing shortage. They are teaching beach-Boers to leave seashells where they belong — at the seashore! Some people even make fake seashells that they hope the hermit crabs will like. For example, a group called Project Shelter invited people who visited their website to create different designs for hermit crab shells.
These designers had a lot to consider. What kind of material should be used to build a seashells. The material must be light enough for the hermit crab to carry, but strong enough to protect the crab from predators. The man-made shells could not contain glue or any other substance that might harm a hermit crab. Another challenge with building a hermit crab home was the opening to the shell. Too big would mean the crab would not feel safe. Too small would be uncomfortable, and the crab would not want to move in.
The Project Shelter shells are placed in the wild for hermit crabs to find. Lucky hermit crabs can move into these new dream homes.
1. Where can hermit crabs stay safe?| A．In different old seashells. | B．Behind the waste they’ll eat. |
| C．In their own thin outer shells. | D．Under the stones at the seashore. |
| A．The methods to recycle the wastes. | B．The ways to help the hermit crabs. |
| C．The materials of seashells. | D．The designs of websites. |
| A．man-made | B．perfect | C．hard | D．comfortable |
| A．The Project Shelter Group. | B．The shortage of the seashell. |
| C．New homes for hermit crabs. | D．The recyclers of the nature. |
