1 . The air conditioner is nearly 100 years old, but the technology is essentially the same as it used to be. Although it has made our lives easier and more comfortable, this all comes at a cost. The cooling of our air is responsible for 10% of the planet’s electricity consumption. And as the world heats, demand for air conditioners will continue to grow. This, in turn, will increase the influence that cooling machines have on the climate, thus warming the Earth further and creating a vicious cycle.

The current technology is unsustainable. That’s why a group led by RMI, a nonprofit environmental research organization, has launched the Global Cooling Prize, a $1-million competition to design of the next generation of air cooling systems. The proposed designs employ a wide range of technologies. Barocal, a Cambridge University startup, uses solid-state cooling technologies instead of traditional liquid refrigerants (制冷剂) that may leak out over time. Meanwhile, a proposal from Kraton, a Texan chemical engineering company, simply uses water, completely doing away with the main mechanical component of air conditioners, the compressor, to make the design more affordable. Others focus on the limitations of current air conditioning units, such as the lack of control over both temperature and humidity (湿度) at the same time. The design proposed by US startup M2 Thermal Solutions allows users to set both a specific temperature and the level of humidity in a room.

It’s difficult to tell what these proposed new machines will look like before the actual machines are built, but it’s arguable that they will create something new, as most of the shortlisted designs are based on fundamentally different technology compared to traditional devices.

The overall winner, announced in November 2021, will be awarded $1 million in prize money. This is when the real challenge begins: convincing the world that traditional air conditioners need replacing. “The current industry is worth more than $100 billion and has a well-established value chain from manufacturing (生产) to distribution to after-sales support,” said Vijay Mhetar, Kraton’s senior vice president. “Any new design will need to have minimum barriers for customer adoption and have a similar supply chain established.”

2 . After being lost for three decades, this tiny deer-like species has finally been rediscovered in the forests of Vietnam. The silver-backed chevrotain — also known as the Vietnamese mouse deer — is about the size of a large rabbit. They are shy, enjoy being alone, appear to walk on the hips of their hooves (蹄) and have two sharp teeth. Chevrotains typically weigh less than 5 kilograms.

Its last recorded sighting was in 1990, when a team of Vietnamese and Russian researchers obtained a dead chevrotain from a hunter. “Then nothing. So little known about it that the species was one big question mark. For so long, it has seemingly only existed as part of our imagination,” said Vietnamese biologist Any Nguyen.

One of the biggest challenges was deciding where to start the search. After several interviews with local villagers who reported seeing a grey mouse deer, a field team set three camera traps for five months. “We had these two areas separated by quite some distance — one in the southern part of Vietnam and the other much further north,” said Andrew Tilker, Asian Species Officer at the Global Wildlife Conservation. This resulted in 275 photographs of the species. The team then set up another 29 cameras in the same area, this time recording 1,881 photographs of the animal.

Tilker also warned that just because this species was found relatively easily, it doesn’t mean it’s not under threat. “This might represent the last population or one of a handful populations, in which case we need to take action immediately to put conservation measures in place to ensure its survival.”

The team is now setting out to determine how large and stable this population of chevrotains is, assess the wider distribution of the species, and explore the threats to its survival. As part of the first-ever comprehensive survey on the species, the team began camera trap surveys in October in two additional areas. They will use all of the information that they gather to set up a project that strengthens the conservation of the species across its range.