We already know the fastest, least expensive way to slow climate change: Use less energy. With a little effort, and not much money, most of us could reduce our energy diets by 25 percent or more—doing the Earth a favor while also helping our wallets.

    Not long ago, my wife, PJ, and I tried a new diet—not to lose a little weight but to answer an annoying question about climate change. Scientists have reported recently that the world is bending up even faster than predicted only a few years ago, and that the consequences could be severe if we don't keep reducing emissions(排放) of carbon dioxide (CO₂ ) and other greenhouse gases that are trapping heat in our atmosphere.

    We decided to try an experiment. For one month we recorded our personal emissions of CO₂. We wanted to see how much we could cut back, so we went on a strict diet. The average US household(家庭) produces about 150 pounds of CO₂  a day by doing common-place things like turning on air-conditioning or driving cars. That's more than twice the European average and almost five times the global average, mostly because Americans drive more and have bigger houses. But how much should we try to reduce?

    For an answer, I checked with Tim Flannery, author of The Weather Makers: How Man is Changing the Climate and What it Means for Life on Earth. In his book, he had challenged readers to make deep cuts in personal emissions to keep the world from reaching extremely important tipping points, such as the melting(融化) of the ice sheets in Greenland or West Antarctica. "To stay below that point, we need to reduce CO₂  emissions by 80 percent," he said.

    Good advice, I thought. I'd opened our bedroom windows to let in the wind. We'd gotten so used to keeping our air-conditioning going around the clock. I'd almost forgotten the windows even opened. We should not let this happen again. It's time for us to change our habits if necessary.

Five years ago, David Smith wore an expensive suit to work every day. "I was a clothes addict(有瘾的人)," he jokes. "I used to carry a fresh suit to work with me, so I could change if my clothes got wrinkled(有褶皱的)." Today David wears casual clothes (便装) to the office. He hardly ever wears a necktie. "I am working harder than ever." David says, "and I need to feel comfortable."

More and more companies are allowing their office workers to wear casual clothes to work. In the United States, the change from formal to casual office wear has been gradual. In the early 1990s, many companies allowed their employees to wear casual clothes on Friday. This became known as "casual Friday". "What started out as an extra one-day-a-week benefit for employees has really become an everyday thing." said business consultant Maisly Jones.

Why have so many companies started allowing their employees to wear casual clothes? "One reason is that it's easier for a company to attract new employees if it has a casual dress code." "A lot of young people don't want to dress up for work," says Owen Black, the owner of a software company, "so it's hard to hire people if you have a conservative (保守的) dress code." Another reason is that people seem happier and more productive when they are wearing comfortable clothes. In a study conducted by Levi Company, 85 percent of employers said that they believe that casual dress improves employee morale (心境, 士气). Only 4 percent of employers said that casual dress has a negative influence on productivity. Supporters of casual office wear also argue that a casual dress code helps them save money. "Suits are expensive, if you have to wear one every day," one person said. "For the same amount of money, you can buy a lot more casual clothes."

How Women Were Freed From Their Homes

    As late as 1800, a woman's only place was in her home. Women in business were unheard of. No respectable woman would dream of entering what was strictly a “man's world”. Even if she would, what could she do? Men were sure that no woman could do a job well outside her home.  This was a widely-accepted idea. When the famous Bronte sisters began writing books in 1846, they had to resort to using men's names as aliases.

    Teaching was the first profession opened to women, soon after 1800. But even that was not easy for women to take because most high schools and colleges were open only to men. Oberlin College in Ohio was the first college in America to take in women.

    Nursing was regarded as a respectable profession for women only after Florence Nightingale won high credit for her nursing career and became famous. Miss Nightingale opened the first training school for nursing in 1860 in England.

    The invention of typewriters in 1867 helped to bring women out of their homes to join the business world. Because women are careful and have nimble fingers, businessmen found that they were well suited to this kind of work.

    By 1890, tens of thousands of women were working in schools, hospitals, shops, offices, and factories both in England and the States. Some even managed to become doctors or lawyers. The idea of women working in business and other circles was accepted. 

    Recent summer temperatures in parts of Australia were high enough to melt asphalt. As global warming speeds up the heat and climatic events increase, many plants may be unable to cope. But at least one species of eucalyptus tree can resist extreme heat by continuing to “sweat” when other essential processes stop, a new study finds.

    As plants change sunlight into food, or photosynthesize (光合作用), they absorb carbon dioxide through pores on their leaves. These pores also release water via transpiration(蒸腾), which circulates nutrients through the plant and helps cool it by evaporation(蒸发). But exceptionally high temperatures are known to greatly reduce photosynthesis—and most existing plant models suggest this should also decrease transpiration, leaving trees in danger of fatally overheating. Because it is difficult for scientists to control and vary trees' conditions in their natural environment, little is known about how individual species handle this situation.

    Ecologist John Drake of the S.U.N.Y. College of Environmental Science and Forestry and his colleagues grew a dozen Parramatta red gum (Eucalyptus parramattensis) trees in large, climate-controlled plastic pods that separated the trees from the surrounding forest for a year in Richmond, Australia. Six of the trees were grown at surrounding air temperatures and six at temperatures three degrees Celsius higher. The researchers withheld (扣留) water from the surface soil of all 12 trees for a month to imitate a mild dry spell, then induced a four-day “extreme” heat wave: They raised the maximum temperatures in half of the pods（three with surrounding temperatures and three of the warmer ones）— to 44 degrees ℃.

    Photosynthesis ground to a near halt in the trees facing the artificial heat wave. But to the researchers' surprise, these trees continued to transpire at close-to-normal levels, effectively cooling themselves and their surroundings. The trees grown in warmer conditions coped just as well as the others, and photosynthesis rates bounced back to normal after the heat wave passed, Drake and his colleagues reported online in Global Change Biology.

    The researchers think the Parramatta red gums were able to effectively sweat — even without photosynthesis — because they are particularly good at tapping into water deep in the soil. But if a heat wave and a severe drought (干旱) were to hit at the same time and the groundwater was exhausted, the trees may not be so lucky, Drake says.

    Other scientists call the finding encouraging. “It's definitely good news,” says Trevor Keenan, an ecologist at Lawrence Berkeley National Laboratory, who was not part of the study. “It would be very interesting to know how this translates to other species,” he adds. Drake hopes to conduct similar experiments with trees common in North America.

    The annual World Economic Forum took place in Davos, Switzerland, in Jan. 23-26, 2018. What did Chinese entrepreneurs （企业家）speak in the forum? Are there some quotable quotes for you?

    Jack Ma, founder and executive chairman of Alibaba Group

    "I think globalization cannot be stopped — no one can stop globalization, no one can stop trade. If trade stops, the world stops. Trade is the way to dissolve (结束) the war not cause the war," said Ma in Davos, "Google, Facebook, Amazon and Alibaba — we are the luckiest companies of this century. But we have the responsibility to have a good heart, and do something good."

    Richard Liu, founder and chief executive officer of JD

    "Business is not only a way to make money but also a way to contribute yourself, to help people," Liu said in a speech in Davos. "How can we face the fractured (分化的) world? That's the topics of the Davos this year. I think a very important thing in business is cooperation. If we can unite, work together, if we work very closely, I think we can bring more hope to the people and we can build more trust between the people, countries and companies and partners," he said.

    Jane Sun, CEO of Ctrip

    "Tourism is a sunrise industry. Since I entered Ctrip, every year there are new comers, which, first of all, shows that tourism is booming." Sun told Sina.com in Davos. "We invested heavily in ABC. A refers to AI, B is big data, and C is cloud computing. As we continue to expand overseas, these three will be very good weapons for us. So we think those mean opportunity," she said.

    Hu Xiaoming, president of Aliyun

    "In 2018, people will see the development in various countries more closely connected with cloud computing. More manufacturing enterprises and financial institutions will start to use ‘cloud', and cloud computing will increase the efficiency of technology and finance," Hu told Xinhua in Davos.

    When the weather is good, most children would like to play outside. So we asked some kids and their parents whether the following toys kept them happy.

    All Surface Swingball, $35.99

    Played by Martin, nine, and five-year-old Alex in Crewe, Cheshire.

    Mother Jennifer says, "The boys thought the toy was excellent and really wanted to play with it. It can be played with alone or with another child. It's for the right age range but I believe the toy can be played with by all ages and is suitable for the whole family."

    Rubberwood Quoits Set, $13.99

    Played by Jessica, four.

    Mother Lucy Hayburst, 37, in Chichester, West Sussex, says, "Jessica played with this toy for a few minutes but quickly stopped playing with it. Since we bought this toy for her, she only played several times. The quality is very good. It can be played with by one child or more. Besides, I believe it's more suitable for older kids."

    Wooden Animal Skittles, $14.99

    Played by Matthew, two.

    Father Richard Lee, 36, from Dartford, Kent, says, "Matthew was very interested in the toys and liked to play with them, but that only lasted for around five minutes. The skittles were fun at first but that feeling soon disappeared. Two or more children can play with the toy together. And I think they are most suitable for kids aged between three and seven. Our youngest son, Ethan, just kept trying to eat the lion's head."

    First Tailball Net Set, $22

    Played by James, five.

    Mother Sarah Schwar, 39, from Grays, Essex, says, "James loved the toy." He enjoyed balls so it was perfect for him. We used it in the summer as it was easy to take on trips. It is suitable for kids over five years old. I think the price is fair and your children deserve it."