【推荐1】Climate change will bring and has already brought a wide variety of threatening destruction to human existence. Some of these are well-known and already operative, like the wildfires racing along California’s freeways or the permanent droughts that have been upsetting Mediterranean farmers. But are these all terrible disasters we can come up with that are brought about by climate change?

Absolutely not. None of the challenges posed by our warming climate has appeared larger in the popular imagination than sea-level rise, as global populations and wealth are heavily concentrated in low-lying coastal cities. The best available models suggest that 37 million people currently live in places that will be below high tide by 2050-in an optimistic low-carbon-emissions scenario (设想).

Or rather, that’s what such models suggested before this week. On Tuesday, a new study revealed that those alarming statistics were wildly inaccurate. The actual impacts of sea-level rise are going to be much, much worse.

Previous estimates of the impact that rising tides would have on coastal cities relied on essentially a three-dimensional map of Earth obtained from satellite readings. But those readings were fundamentally unreliable because they often measured the planet’s upper surfaces — such as treetops and tall buildings — rather than its ground level. These mistakes led scientists to overestimate the elevation (海拔) of many regions of Earth.

In a new study published by the journal Nature Communications, scientists from Princeton, University detail this methodological problem, then use artificial intelligence to determine the previous literature’s error rate. Their research yields some amazing updates to our conventional understanding of what the next century has in store for our coastlines.

In its optimistic scenario, the Princeton study projects that lands currently occupied by 150 million people will lie below high tide in 2050. But as warming destroys many of the world’s agricultural regions, climate change could accelerate migration from rural areas to coastal cities.

The new study does include one piece of slightly encouraging news. While previous models suggested that 28 million humans currently live in places that already lie below high tide, the actual number is closer to 110 million — which means seawalls and other barriers have proven sufficient to keep many cities dry even as sea levels have risen around them. Still, the scale of barrier construction necessary to save low-lying cities from collapse is now, apparently, far greater than previously understood when the task already looked terribly expensive, particularly for developing countries.

If the Princeton researchers’ projections are correct, avoiding mass death and suffering in the coming decades will require not only rapidly reducing carbon emissions and strengthening construction of seawalls but also furthering mass migrations away from low-lying cities and islands and toward higher ground.

【推荐2】Most autonomous vehicles test-driving in cities navigate by using 3-D maps marking every edge of roadside with almost centimeter-level accuracy. But few places have been mapped in such detail, which has left most areas like smaller towns inaccessible to those driverless cars.

Researchers at the Massachusetts Institute of Technology (MIT) now have developed a new navigation system that guides autonomous vehicles without such accurate maps. This technology can help driverless cars travel almost anywhere.

The navigation system maps out a course down unfamiliar roads much as a human driver would by continually scanning its surroundings, with a laser sensor, to measure how close it is to the edges of the road. Meanwhile, the car also follows a tool like a smart phone map app that provides directions to its destination, as well as information about the rules of the road, such as speed limits and the positions of stoplights. Teddy Ort, a roboticist at MIT, test-drove a car equipped with this navigation system on a one-way road. It slowly traveled one kilometer without any human assistance.

This system assumes that a car has a clear path down the road, but it can be paired with other existing computing technology to discover in-road obstacles, says Ort. The researchers also plan to build a version of this system which can spot markings painted on streets, so that the car can drive on two-way roads. “Self-driving cars with this navigation system may need other sensors to work in different conditions,” says Alexander Wyglinski, an electrical engineer at Worcester Polytechnic Institute. “Since laser sensors don't work well in rain or snow, these cars might need additional imaging technologies to drive safely in bad weather."

【推荐3】Can dogs and cats live in perfect harmony in the same home? People who are thinking about adopting a dog as a friend for their cats are worried that they will fight. A recent research has found a new recipe of success. According to the study, if the cat is adopted before the dog, and if they are introduced when still young (less than 6 months for cats, a year for dogs), it is highly probable that the two pets will get along swimmingly. Two-thirds of the homes interviewed reported a positive relationship between their cat and dog.

However, it wasn’t all sweetness and light. There was a reported coldness between the cat and dog in 25% of the homes, while aggression and fighting were observed in 10% of the homes. One reason for this is probably that some of their body signals were just opposite. For example, when a cat turns its head away it signals aggression, while a dog doing the same signals submission.

In homes with cats and dogs living peacefully, researchers observed a surprising behaviour. They are learning how to talk each other’s language. It is a surprise that cats can learn how to talk ‘Dog’, and dogs can learn how to talk ‘Cat’.

What’s interesting is that both cats and dogs have appeared to develop their intelligence. They can learn to read each other’s body signals, suggesting that the two may have more in common than we previously suspected. Once familiar with each other’s presence and body language, cats and dogs can play together, greet each other nose to nose, and enjoy sleeping together in the sofa. They can easily share the same water bowl and in some cases groom (梳理) each other.

The significance of this research on cats and dogs may go beyond pets —to people who don’t get along, including neighbors, colleagues at work, and even world superpowers. If cats and dogs can learn to get along, surely people have a good chance.

【推荐2】When she was just 9 years old, Hilde Lysiak became famous across the United States for reporting on difficult news stories. Now Hilde has written a book telling her own story, and sharing some of the challenges she faced.

Hilde Kate Lysiak’s father was a reporter for the New York Daily News. When she was young, he often took her to work with him, and she developed a strong interest in news stories and reporting. When she was 8, Hilde started her own newspaper, called the Orange Street News (OSN). Her family lived on Orange Street. Hilde did the writing, her sister Izzy took pictures, and her father helped her organize and print the newspaper. Following the rules her father had taught her, she researched and reported stories in her monthly newspaper.

OSN suddenly became famous when a murder happened in town, and 9-year-old Hilde was the first person to report it. Soon, news organizations around the country were doing stories on Hilde. Some people criticized her parents for allowing her to report on something as unpleasant as a murder. Others criticized Hilde for “pretending to be a reporter”. Some people even suggested she should be playing with dolls.

Hilde was upset by the complaints. She responded with a You Tube video. “I never began my newspaper so that people would think I was cute,” she said. “I want to be taken seriously. I’m sure other kids do, too.” That wasn’t the last time Hilde had trouble getting people to take her seriously. Sometimes, it was because of her age. Other times, it was because she was a girl. But she never let that stop her. Hilde continued reporting.

Hilde’s activities as a reporter have made her famous, and she has earned several awards. With her father, Hilde has written a series of books for young people, called Hilde Cracks the Case. The books are based loosely on stories that Hilde wrote. The books have now been turned into a TV show called Home Before Dark.