1 . American researchers say they have developed a method to remove carbon dioxide (CO₂) from the sea. The researchers say the process can be an additional way to help reduce CO₂ from the environment to fight the effects of climate change.

Plants and currents in the ocean absorb large amounts of CO₂ from the atmosphere. The sea is estimated to have drawn in about 30 percent of carbon emissions since the Industrial Revolution. But carbon emissions also make oceans more acidic (酸性的). It can hurt coral reefs, which are sensitive to ocean acidity. Reef damage then do damage to the growth of many kinds of sea life.

Gaurav Sant, director of UCLA’s Institute for Carbon Management, said the technology is meant to use the ocean’s natural abilities to reduce carbon levels in the sea. The process sends an electrical charge through seawater flowing through tanks on a large boat. That sets off a series of chemical reactions that turn the carbon emissions into a solid mineral that includes calcium carbonate (碳酸钙). The seawater then returned to the ocean and can pull more carbon dioxide out of the air. The calcium carbonate settles to the sea floor.

The process has already been demonstrated in California. Researchers are working on plans to launch another project in Singapore. The two projects are expected to be fully operational by 2025. Researchers say they are expected to remove thousands of tons of CO₂ per year. If successful, the plan is to build additional centers to remove millions of tons of carbon each year.

But experts say even if that amount of carbon can be removed, that is still thousands of times less than what will be needed to effectively reduce climate change. Margaret Leinen, director of an ocean research center, said, “While the process will likely be effective, I question how much effect it will have on climate change over a long period.” Sant said the success of such technology will greatly rely on “how fast you can build the centers”.

3 . Jeannette Frescas was not concerned about the Thomas Fire until the fire reached her neighborhood in Ventura, California. “At midnight, I woke up with a flashlight in my face,“ Frescas told CNN.“I looked out of my window and there were flames, a hundred feet, all around us.”

Like many residents, Frescas was caught off guard by the fire that had roared across Southern California for 13 days. She’s one of tens of thousands of residents who got into cars and fled as winds drove the third-largest fire in modern state history through Ventura and Santa Barbara counties.

“What was once a paradise (天堂) was like a war zone (地带),” Frescas said of her apartment, which was destroyed by the fire. “It’s the scariest thing I’ve been through in my entire life.” Ventura resident Patricia Rye woke up to her son-in-law pounding on her door. She didn’t get a chance to pack any valuables. “I didn’t have time to take anything,” Rye said. “My wallet, or any of my personal things.”

The fire was so terrible that more than 8,400 firefighters were working around the clock to save lives and contain (控制) it. Twelve thousand people were evacuated (撤离) in Santa Barbara County, with animals at the local zoo threatened as well. Santa Barbara Zoo closed and many animals were placed into cages in case of possible evacuations. The zoo had kept most animals indoors, away from smoke.

Meanwhile, residents who had evacuated their homes in Ventura County-where the fire began-were allowed to return on Saturday. Jim Holden considered himself lucky that firefighters saved his home and items. “They put a water screen between my house and the house next door that was burning in an attempt to save it,“ he said. “They broke in and they saved my family photos and my computer, and things that they thought would be important to me.”

4 . Urban agriculture, the practice of farming within the restrictions of a city, is becoming increasingly popular and is viewed as a sustainable alternative to big industrial farms. By some estimates, between 20% and 30% of the global urban population engages in some form of urban agriculture. But until recently, its carbon footprint remains understudied.

Using data from 73 low-tech city farms, community gardens and personal plots of land, Newell and his team compared the average carbon emissions of food produced at low-tech urban agriculture sites to those of conventionally grown crops. The team found that because of urban gardens’ relatively low yields, along with the energy used in constructing the planting beds, big-city spuds (马铃薯) were significantly more carbon-intensive than commercially grown ones. This held true even when the researchers factored in emissions from transporting commercially grown produce to often distant grocery stores. That doesn’t mean that growing vegetables in big cities is totally bad, however. “Urban farming is great, ” if imperfect, says Carola Grebitus, a food choice expert. It can be a powerful tool for job creation and education, she says, and a good way to introduce fresh produce to urban “food deserts” where healthy fruits and vegetables are hard to come by. Community gardens can also provide a place to connect with nature, and the added green space can reduce the risks of heat and flooding.

Conscious of these benefits, Newell’s team highlighted several ways to make urban agriculture more sustainable. One option is to be selective about what crops are grown. For instance, tomatoes grown in the soil of open-air urban plots had a lower carbon intensity than tomatoes grown in conventional greenhouses. Another strategy is to rely on existing constructions. Include old structures into a new garden’s design instead of taking down old buildings. Finally, take the local climate, water quality and soil into account. Growing plants that are ill-suited to an area requires more water, energy and pesticides (杀虫剂), all of which affect the environment.

5 . Common water plant could provide a green energy source. Scientists have figured out how to get large amounts of oil from duckweed, one of nature’s fastest-growing water plants. Transferring such plant oil into biodiesel (生物柴油) for transportation and heating could be a big part of a more sustainable future.

For a new study, researchers genetically engineered duckweed plants to produce seven times more oil per acre than soybeans. John Shanklin, a biochemist says further research could double the engineered duckweed’s oil output in the next few years.

Unlike fossil fuels, which form underground, biofuels can be refreshed faster than they are used. Fuels made from new and used vegetable oils, animal fat and seaweed can have a lower carbon footprint than fossil fuels do, but there has been a recent negative view against them. This is partly because so many crops now go into energy production rather than food; biofuels take up more than 100 million acres of the world’s agricultural land.

Duckweed, common on every continent but Antarctica, is among the world’s most productive plants, and the researchers suggest it could be a game-changing renewable energy source for three key reasons. First, it grows readily in water, so it wouldn’t compete with food crops for agricultural land. Second, duckweed can grow fast in agricultural pollution released into the water. Third, Shanklin and his team found a way to avoid a major biotechnological barrier: For the new study, Shanklin says, the researchers added an oil-producing gene, “turning it on like a light switch”by introducing a particular molecule (分子) only when the plant had finished growing. Shanklin says, “If it replicates (复制) in other species-and there’s no reason to think that it would not — this can solve one of our biggest issues, which is how we can make more oil in more plants without negatively affecting growth.”

To expand production to industrial levels, scientists will need to design and produce large-scale bases for growing engineered plants and obtaining oil — a challenge, Shanklin says, because duckweed is a non-mainstream crop without much existing infrastructure (基础设施).

6 . Students at the Calhoun School in New York City have much more than a roof over their heads. They have a rooftop garden, with lush grass, colorful flowers and fragrant herbs. “Green roofs” are sprouting up all over, from schools to city skyscrapers. And roofs aren’t the only things going green. Architects are finding all sorts of new ways to build buildings that are easier on the environment. These schools, homes, and offices are called “green buildings”.

Normally it takes a lot of energy to run appliances. Too often, that energy comes from burning fossil fuels. So green buildings are designed to do all these things with much less energy. An energy-smart building starts with thick walls. A layer of insulation (隔热材料) traps air to stop heat from passing through. That keeps heat inside in the winter, and keeps heat outside in the summer. This saves energy for heating and cooling.

Heat pumps are another power-saving way to stay comfortable. A ground heat pump moves heat through pipes that run through the ground next to the building. A few feet under the ground, the temperature stays around 10℃ all year round. Water flowing around the pipes helps heat the building in winter and cool it in summer.

Another way to build green is to use recycled materials. That saves the cost and pollution of manufacturing something new. In the Chicago Center for Green Technology, the ceiling tiles (瓷砖) are made of pressed newspaper. The bathroom floors are tiled with recycled glass, and the stall walls are recycled plastic. Builders have found many creative ways to re-use old materials.

As more people become concerned about climate change, more buildings are going green. Green buildings produce less of the gases that warm the planet. City planners like green buildings because they save money. And they are healthier for the people who work and live inside. But you don’t need to build a whole new building. Simple changes like shading windows and planting trees can make any home greener—and a better Earth home for us all.

9 . Rebecca, a wildlife camerawoman, was filming a documentary for the BBC in the Pacific Ocean when she saw something that made her cry: hundreds of  _______   had died because they had  _______  eaten some of the tons of plastic thrown into the sea. Beaches in Honolulu and other Pacific islands were _______ plastic toys, bottles, keyboards, pens, cigarette lighters . Seabirds as well as  other  animals like whales, dolphins, seals, turtles were suffering  _______  thrown-away plastic. The sea and the environment become more and more polluted.

At this point most of us would have felt sad and _______ but Rebecca did differently. In her hometown of Modbury she showed her _______ from the island to local shopkeepers and asked them to do one thing to help—stop using plastic _______ in their shops. To Rebecca's surprise, the shopkeepers_______ and Modbury became the first plastic-bag-free town in Britain. Shops offered  _______ cotton bags or biodegradable(可降解) bags. People in the town got used to taking a shopping bag with them to the supermarket—just like their grandparents had done before plastic bags were  invented . Later, other towns in Britain followed Modbury's  ________ . The small town of Hebden Bridge became the second plastic-bag-free town when four women there saw Rebecca's film and  ________  to act and the people there are happy to change things.

More and more towns around are becoming plastic-bag-free. Now "the bag for life" is part of the national________, and the task of reducing the use of plastic bags has become law. Since October 2015, all shops in the UK must________ five pence for each plastic bag used by each shopper. It's not enough, of course, ________  it's a good start. It also shows us that there is something we can do and that one person ________ a strong enough belief can make a big change to protect the oceans and save the seabirds and sea animals.