The rapid increase of the oil price has brought the world to its senses. Scientists are seeking suitable alternative (替换) but so far in vain. They are considering how they can make better use of the two other major fuels, coal and natural gas, but they have found that neither can replace oil in their economics. In recent years, there has been a growing concern for the environment and coal is not a popular fuel with environmentalists. Natural gas, the purest of the three fuels, is also the most limited in supply.

The answer would seem to lie in nuclear power stations. They need very little fuel to produce enormous amounts of power and they do not pollute the atmosphere. Their dangers, however, are so great and the costs of building them are also high. Not only could one accident in a nuclear power station spread as much radioactivity (放射物) as a thousand Hiroshima atom bombs, but the radioactive waste from these stations is extremely dangerous.

Scientists have recently turned their attention to natural sources of energy: the sun, the sea, the wind and hot spring, of which the sun seems the most promising source for the future. Houses have already been built which are heated entirely by solar energy. However, solar energy can only be collected during daylight hours, and in countries where the weather is unreliable, an alternative heating system has to be included.

However, many scientists are optimistic that new ways of generating large amounts of energy will be successfully developed, but at the same time they fear the consequences. If the world population goes on increasing at its present rate, we may, in fifty years’ time, be burning up so much energy that we would damage the earth’s atmosphere. By raising the temperature of the atmosphere,we could melt the Arctic and Antarctic ice-caps and change the pattern of vegetable and animal life throughout the world——a frightening possibility.

With visitor numbers around the world increasing towards pre-pandemic levels, the issue of overtourism is once again rearing its head. When locals in the charming Austrian lakeside village of Hallstatt staged a blockade(封锁)of the main access tunnel, asking visitors to “think of the children”, it highlighted what can happen when places start to feel overrun by tourists.

The term “overtourism” is relatively new, having been invented over a decade ago to highlight the increasing numbers of visitors taking a toll on cities, landmarks and landscapes. In essence, it is too many people in one place at any given time. There are the wide-reaching effects, such as climate change. Coral reefs, like the Great Barrier Reef and Maya Bay, Thailand are being degraded from visitors diving and touching the corals. More localized issues are affecting locals, too. Renters are being driven out by landlords in favour of turning properties into holiday lets, and house prices are escalating as a result. As visitors and rental properties outnumber local residents, communities are being lost.

Overcrowding is an issue for both locals and tourists. It can ruin the experience of sightseeing for those trapped in long queues, unable to visit museums, galleries and sites without advance booking, rising costs for basics like food, drink and hotels, and faced with the inability to experience the wonder of a place in relative solitude. Justin Francis, co-founder and CEO of Responsible Travel, a tour operator that focuses on more sustainable travel, says “Social media has concentrated tourism in hotspots and worsened the problem, and tourist numbers globally are increasing while destinations have a finite capacity. Until local people are properly consulted about what they want and don’t want from tourism, we’ll see more protests.”

Of the 800 residents in the UNESCO-listed village of Hallstatt, around 100 turned out in August to show their displeasure and to push for a limit on daily visitors and a curfew(宵禁)on tour coach arrivals. Elsewhere, residents in Venice fought long and hard for a ban on cruise ships, with protest flags often hanging from windows. In Rome, sitting at popular sites, such as the Trevi Fountain and the Spanish Steps, has been restricted by the authorities.

There are ways to better manage tourism by promoting more off-season travel, limiting numbers where possible and having greater regulation within the industry. Encouraging more sustainable travel and finding solutions to reduce friction between residents and tourists could also have positive impacts. Promoting alternative, less-visited spots to redirect travelers may also offer some benefits.

In the long history of pipe-assisted drinking—beginning with the gold beer-sipping tubes of the Sumerians —Starbucks’s plastic straws(吸管)knew they had some advantages over the rest. Their tight white wrapping carried not only English words but a French style. They stood straight and tall as a stalk (秆)of wheat, with no ugly appearance. And their colour was beautiful. It was darker than the leaves of spring, and lighter than the Washington forests and the logo of the company. But despite all that, they were to disappear by 2020, for not being green enough.

Of course, the straws played an important part in daily life. You could build a cottage with them, or make a hat. At best, they might compose a mat. Their nearest relatives were not delicate grasses, but single-use plastic tubes.

Yet this did not concern them, because they had a higher calling:to refresh human beings.Rather than pumping up the customer with hot highly-effective Americanos, they cooled him with less caffeine and more play. People, especially teenagers and children, needed them to socialize, and amuse themselves. All these folk could have drunk their Frappuccino or their iced teas directly from the plastic cup, of course. Some did, ignoring the eager straws standing ready.

Fun was why green straws had been put into use at all. They began their service not when Starbucks was founded, in 1971, but when it introduced the Frappuccino almost three decades later. Green straws marched in, along with whipped cream. They meant happiness. Yet for each of those straws, the Frappuccino and its followers faced a serious challenging. Through the flat plastic lids of iced coffees, now sharply scored with a cross, they were expected to do the same.

However, the straws were thrown to the bin, either in-store or in the street after being used. They lay where they were thrown in woods, or fields, or among the hills. They would never be dust. They had eternal(永久的)life. That’s the reason why they would disappear.