3 . Not much trash and almost no plastic actually gets recycled. About a third of U.S. garbage gets recycled, according to the Environmental Protection Agency’s most recent estimate. The rest goes to landfills, which release greenhouse gases into the atmosphere and pollute their surroundings.

To make recycling easier, many U.S. cities don’t ask Americans to separate paper, glass, metal and plastic. ‘They just ask people to put anything recyclable into one bin and let waste plants do the sorting. But waste plants don’t catch everything. AI is now an essential tool for the world’s waste management leaders. Greyparrot, a tech company has already installed more than l00 AI trash spotters in about 50 sorting facilities.

Greyparrot’s device is, basically, a set of visual and infrared (红外线的) cameras hooked up to a computer, which monitors trash as it passes by on a conveyor belt and labels it under 70 categories, from loose bottle caps to books to aluminum cans. Waste plants could connect these AI systems to sorting robots to help them separate trash from recyclables more accurately. They could also use the AI as a quality control system to measure how well they’re sorting trash from recyclables. That could help plant managers adjust their production lines to cover more recyclables, or cheek that a bundle of recyclables is free of pollutants, which would allow them to sell at a higher price.

In the next few years, some recycling companies plan to retrofit (改良) thousands of material- recovery facilities with Al trash - spotting tools. Of these companies, Bollegraaf has built thousands of these facilities, including 340 in North America, accounting for a majority of the recovery plants in the world.

The trash-spotting computers could one day help regulators punish companies that produce tsunamis of non - recyclable packaging because the AI systems are so accurate that they can identify the brands on individual items. Putting the AI tools in thousands of waste plants can raise recycling percentage. If the needle can be moved by even 5 to 10 percent, that would be a phenomenal outcome for greenhouse gas emissions and environmental impact.

5 . Djukic is a biology and chemistry student at John Carroll University. She never thought that one day she would be in a classroom where an English teacher asked her to play a board game in order to learn about climate change.

Debra Rosenthal is the professor of the class. At first, Djukic said she was uncertain about Rosenthal’s board game idea. “I was just like: ‘this is interesting, but how much are we actually going to take away from it?”

Rosenthal thought her students would gain a greater understanding about how their own ideas and experiences affect climate change. Students do not compete against each other. They work together to choose the best plan of action. The game is different from board games such as Monopoly, where the goal is to win. Rosenthal said she hoped the games would give students a chance to talk about climate change in a new way.

“By playing the games, it’s a way to be social, to engage in conversation. There has to be a lot of energy around the table. It’s very collaborative. And in the game that I chose to play, they really were able to work together and try to come up with a solution so that the planet was not destroyed.”

During the class, she said, students laughed, disagreed and had to call for votes as a way to decide how to move forward in the game. Djukic said it was a “way to have fun...while also learning about such a serious subject.”

The games are global, Djukic said. That is because she and her classmates said they were able to see how one player’s decision about agriculture affected another player on the other side of the world.

She said the games showed her that “in the game of climate change and the climate crisis, no individual wins.” “It’s either we all suffer from this, or we all somehow collaborate to work our way out of this and turn the clock back on climate change.”

7 . The streets and roofs of cities all absorb heat, making some urban areas hotter than rural ones. These “urban heat islands” can also develop underground as city heat spreads downward, and subway tracks and other subsurface infrastructure(基础设施) also constantly radiate warmth into the surrounding earth.

A new study of downtown Chicago shows underground hotspots may threaten the very same structures that give off the heat in the first place. “Without anyone realizing it, the city of Chicago’s downtown was deforming,” says study author Rotta Loria, an environmental engineer.

Humans aren’t the only potentially affected. “For a lot of things in the subsurface, it’s kind of ‘out of sight, out of mind’,” says Grant Ferguson, a geologist. But the underground world is full of creatures that have adapted to subsurface existence such as insects and snails. As the temperature rises because of climate change and underground urban development, scientists are keeping eyes on the potential implications for underground ecosystems.

But the question of how underground hotspots could affect infrastructure has gone largely unstudied. Because materials expand and contract with temperature change, Rotta suspected that heat coming from underground could be contributing to wear and tear on various structures. To understand how underground temperature difference has affected the ground’s physical properties, he used a computer model to simulate(模拟) the underground environment from the 1950s to now—and then to 2050. He found that by the middle of this century, some areas may lift upward by as much as 0.50 inch or settle by as much as 0.32 inch, depending on the soil makeup of the area involved. Though these may sound like small displacements, Rotta says they could cause cracks in the foundations of some buildings, causing buildings to fall.

Kathrin Menberg, a geoscientist in Germany, says these displacement predictions are far beyond her guesses and could be linked to the soft, clay-heavy soils. “Clay material is particularly sensitive,” she says, “It would be a big issue in all cities worldwide that are built on such material.”

Like climate change above the surface, underground changes occur gradually. “These effects took decades to develop,” Ferguson says, adding that increased underground temperatures would likewise take a long time to dissipate on their own. “We could basically turn everything off, and it’s going to remain there, the temperature signal, for quite a while.”

But Ferguson says this wasted heat energy could also be reused, presenting an opportunity to both cool the subsurface and save on energy costs. Still, this assumption could fail as aboveground climate change continues to boost underground warming. However slowly, this heat will gather beneath our feet. “It’s like climate change,” Rotta Loria says. “Maybe we don’t see it always, but it’s happening.”

10 . On Tuesday, Virgin Atlantic flew a large passenger jet from London to New York using 100% “Sustainable Aviation（航空） Fuel（SAF）”. The flight was meant to show that it’s possible to fly using cleaner fuels.

The fuel used on the flight was mainly made from used cooking oils and animal fats. A small part of the fuel was made from corn waste. Virgin Atlantic says that using SAF cuts the flight’s pollution by 70%. SAF still pollutes when it’s burned, just like regular jet fuel. However, the difference is in how the fuels are made.

SAF is made from plants （and related animal products） that once absorbed carbon dioxide （CO₂） from the air. When SAF burns, it just releases this same CO₂ again. That’s different from jet fuel, which is made from oil exploited from underground, releasing CO₂ that was deeply buried.

SAF may sound great, but it still has many problems. For one thing, SAF costs five times as much as regular jet fuel. That helps explain why only one-tenth of 1% of the fuel airlines currently use is SAF. Virgin Atlantic is hoping that its flight will encourage more companies to produce SAF and that this will bring the price down.

But even if the price of SAF drops, critics say there are still big problems with it. They say it’s easy to make small amounts of SAF out of plant waste. But to make as much SAF as the airlines really need would require farmers to grow plants for fuel instead of for eating. This could also lead to more forests being cut down for farmland.

Airlines like SAF because it can be used now in existing planes with no changes. They hope it will help quickly reduce airplane pollution until non-polluting fuels are developed.

Governments seem to agree that SAF is a step in the right direction. Both the United States and the European Union have set targets that will sharply increase the use of SAF in coming years.