Scientists are seeking new and creative ways to deal with climate change. As well as reducing our carbon dioxide sent into the air, scientists say we must remove the gas from the air to keep Earths temperature down.

One expert has now suggested pouring carbon dioxide into deep trenches (海沟), forming vast liquid lakes, Steve Goldthorpe, an energy analyst based in New Zealand, says the lakes could forever hold vast quantities of carbon dioxide. This is because once the gas reaches a depth of 3,000 meters it is denser (密度大) than water, meaning it naturally sinks to the seafloor.

“If liquid CO₂ were to be placed in such a trench, it would be 7 per cent more dense than seawater and could remain forever as a lake of liquid CO₂ on the ocean floor,” Mr Goldthorpe wrote in his paper, “the stored carbon dioxide could become solid over time, which would stop it mixing with ocean currents.”

Previously, experts have suggested burying the extra carbon dioxide deep underground, possibly in abandoned (废弃的) oil and gas fields. While first tests have shown that this method has potential, scientists are still unsure whether people would accept the fix.

Carbon dioxide lakes do form naturally in the cold, high-pressure depths of the ocean, but they are rare.

Researchers have previously given up the idea of ocean CO₂ storage because it can make the water more acidic, which may affect ocean ecosystems. Mr Goldthorpe recognizes this in his paper, writing, “Any influence on deep ocean ecosystems would need to be examined.”

Landscaping (人造景观) refers to man-made features of a landscape such as driveways, walls, steps, and other human-made structures. It has many sustainability benefits.

Replace Lawns (草坪)

Fertilizers and pesticides (化肥和杀虫剂) help establish a beautiful lawn. 【小题1】 If you replace lawns with landscape, you’ll use fewer chemicals and do less harm to the environment.

Use Less Water

【小题2】 So it can save hundreds of gallons of water and reduce the carbon emissions (排放) used to provide that water cleanly.

Use Locally-Produced Materials

Materials for landscaping are almost all produced locally, due to the high shipping cost. 【小题3】

Lower Garden Maintenance (维护)

Usually, Americans spend two hours per day on lawn and garden care. 【小题4】 That often means less energy used to run some garden equipment.

Reduce Ice Build-up

Sustainable landscape allows stormwater to drain (流) into the soil. 【小题5】 This means safer walkways or driveways, and a reduced need for salt for de-icing (除去……上的冰).

It is the year 3000. I come to a place where I can’t see any water, plants or animals but black clouds in the sky and sand everywhere. It’s very dry so I drink some water that I carry with me. A native sees what I do and asks “What is it?” I pour some water and tell him it’s called water. “Oh, I’m so lucky that I can see water!” the man shouts in an excited voice. “You have never seen water? But how can you live without water?” I ask.

“Harry, get up, it is 7 o'clock, or you will be late!” a voice comes to my ears. “Oh! What a strange dream I dreamed just now!”

In class, I always think of that dream. And I also think of the fresh air, clean water, blue sky, green plants and animals in our world nowadays. How beautiful our life is!

But in order to make more money, people have built more and more factories. These factories send out waste smoke and water with chemicals which are harmful to the environment. The pollution is becoming worse and worse, and as a result, some animals and plants die out. With the development of agriculture, farmers spray aerosol (喷雾) and fertilizer, which also pollute the water and air. In the street the cars and buses are sending out heavy smoke which pollutes the air badly. Even tourism is harmful to the environment. When some tourists travel somewhere, they throw the plastic bags and rubbish onto the ground.

These behaviors are polluting the environment and the environment will become the greatest problem of the world. We shouldn’t pollute the environment any more. Otherwise more and more animals and plants will disappear. And maybe my dream will come true in the future.