2 . More than 50 percent of the largest lakes in the world are losing water, storing less water than they did three decades ago, according to a new assessment published today in Science. The key causes are not surprising: The warming climate and unsustainable human consumption.

Lead author Fangfang Yao, a climate fellow at University of Virginia, and his team created a technique to measure changes in water levels of nearly 2,000 of the world’s biggest lakes and reservoirs (水库), which represent 95 percent of the total lake water storage on Earth.

They used 250,000 lake-area pictures taken by satellites between 1992 and 2020 to survey the area of 1,972 of Earth’s biggest lakes. They collected water levels from nine satellite altimeters (测高计) and used long-term water levels to reduce any uncertainty. For lakes without a long-term level record, they used recent water measurements made by newer instruments on satellites. Combining recent level measurements with longer-term area measurements allowed scientists to reconstruct the volume of lakes dating back decades.

The result was staggering: 53 percent of lakes globally experienced a decline in water storage. The authors compare this loss with the size of 17 Lake Meads, the largest reservoir in the United States.

To explain the trends in natural lakes, the team used recent advancements in water use and climate modeling. “Climate change and human water consumption were mainly responsible for the global net decline in natural lake volume and water losses in about 100 large lakes,” Yao said. “And many of the human and climate change footprints on lake water losses were previously unknown, such as the dryness of Lake Good-e-Zareh in Afghanistan.”

And their research offers an understanding into possible solutions. Yao said, “If human consumption is a large cause of lake water storage decline, then we can adapt and explore new policies to reduce large-scale (大范围) declines.” This happened in one of the lakes the team studied, Lake Sevan in Armenia. Lake Sevan has seen an increase in water storage, in the last 20 years, which the authors linked to the enforcement (实施) of conservation laws on water withdrawal since the early 2000s.

3 . On April 10, the University of Utah became officially Bee Campus certificated. This process was started by senior Zoē Bross in her second year on campus. Bee Campus USA hopes to protect the native pollinators (传粉者) on college campuses by increasing the number of native plants, providing nest sites, reducing the use of pesticides, and offering educational opportunities that help with pollinator conservation.

After first hearing her school wasn’t certificated a Bee Campus and finding becoming Bee Campus certificated would give the University more point s on the Advancement of Sustainability in Higher Education Sustainability Tracking, Assessment & Rating System (STARS) program, which decides ratings to campuses according to their sustainable efforts, Bross wanted to help.

There are many requirements to become Bee Campus certificated. The first major step for Bross was to create a standing Bee Campus committee with a mix of students and staff. Bross tried to reach out to professors and people specializing in this field. After many efforts, the program was finally passed through and a garden for it was created.

Over 100 people showed up to help plant in the garden. After the planting was done, Grounds, responsible for planting the pollinator gardens, set up their hydroseeder (水力播种机) and let attendees take turns spraying the hill, with a mixture of water and wildflower seeds, making the area more pollinator-friendly. Rocky, the school robot, even made an appearance, taking turns spraying.

Certificated by Bee Campus USA, Bee Campuses are expected to continue maintaining or improving pollinator habitats on campuses, as well as maintaining an educational online presence. “I see the campus continuing to be very interested,” Bross stated.

Future plans for the campus include more pollinator gardens, native wildflowers, and even bee sculptures to provide new habitats. As for Bross? She pictures herself somewhere warm and sunny in the near future, working in environmental communications and doing something for the change she wants to see in the world.

5 . In an awe-inspiring incident, a young killer whale recently demonstrated remarkable intelligence by seeking assistance from a group of humans to save its trapped mother, which challenged our conventional understanding of wild predators (食肉动物).

The online viral video, shared by Alvin Foo, began with a young killer whale emitting distressing cries towards a group of people on a boat. Recognizing the urgency of the situation, the concerned individuals promptly responded by contacting a rescue team. The young whale’s desperate request for help touched more people’s hearts and set a truly extraordinary chain of events in motion.

As the rescue team arrived, they were amazed to witness the young killer whale’s playful interaction with the humans. The whale appeared elated, seemingly understanding that assistance had finally arrived. This interaction between the mother killer whale and rescuers underlined the potential for mutual understanding beyond the boundary of traditional predator-prey relationships.

The young whale took on the role of a guide, leading the rescue team to its mother trapped in a fishing net. It navigated the water with purpose, as if fully aware that the humans possessed the means to save its mother. This display of intelligence left the rescuers in awe, highlighting the complex cognitive abilities of these magnificent marine creatures. With its guidance, the rescue team swiftly initiated the liberation process, carefully cutting the net to free the trapped whale. Astonishingly, they seemed to understand that the humans were there to help and did as asked.

The instant the mother whale was finally freed, an eruption of joyous cries filled the air. The emotional outpouring conveyed the immense gratitude of both the mother whale and the young whale to the humans who had intervened. As the rescue team made their way back to shore, the two whales swam alongside them. This heart-warming sight emphasized the lasting impact of the rescue. The bond formed through this extraordinary rescue operation was well obvious, proving that the profound connections can be established between various species. The journey back to safety symbolized the victory of compassion over adversity.

6 . Haze (薄雾) and smoke from hundreds of Canadian wildfires covered most of the US Northeast for a second day — Wednesday, with New York City experiencing the world’s worst air quality over the last two days.

New York, the Big Apple became the Big Orange by midday Wednesday as the sky over the nation’s largest city fell into a deep hazy orange. Streets in Manhattan are like what they were like during the pandemic (流行病) as residents again wore masks and cared for warnings from health officials about the impact of PM2.5, which can lead to respiratory (呼吸的) illnesses.

New York Governor Kathy Hochul said on Wednesday that the state was making one million N95 masks available to the public. Approximately 400,000 N95 masks would be distributed at New York state parks, and at subway stations and other locations in New York City, Hochul said at a press briefing. An additional 600,000 masks would be made available at Homeland Security stockpiles (囤聚的物资) for local governments to pick up, she said.

Hochul called the poor air quality “a very serious, dangerous situation”. She recommended that people across the state cancel outdoor activities. “Simply stay indoors. Outdoors is dangerous in just about every part of our state,” the governor said. Officials at the briefing said they had been monitoring any potential rise in respiratory illnesses or health issues due to the poor air quality.

The city’s air was more polluted than all the world’s major cities on Wednesday morning, according to data from Swiss technology company IQAir. Dubai and Delhi came in second and third, respectively. Mike Hardiman, a staff in the National Weather Service, told The New York Times the city “smells like cigars”.

7 . Meteorites (陨石) can offer clues about what the early solar system was like. But finding them is far from difficult. Now, some scientists are turning to drones (无人机) and machine learning to help spot freshly fallen meteorites much more efficiently. “A team of six people on a meteorite-hunting expedition can search about 200,000 square meters per day,” says Seamus Anderson, a planetary scientist in Australia.

Around 2016, Anderson began toying with the concept of using drones to take pictures of the g round to look for meteorites. That idea blossomed into a Ph.D. project. In 2022, he and his colleagues reported their first successful recovery of a meteorite spotted with a drone. They’ve since found four more meteorites at a different site. Drone-based searches are much faster than the standard search way. “You’re going from about 300 days of human effort down to about a dozen or so,” he says.

Anderson and his workmates have used drones to search for meteorites in remote parts of Western Australia and South Australia. The team is tipped off about a fall site by networks of ground-based cameras that track meteoroids flashing through the Earth’s atmosphere. The researchers have to do a series of fun but difficult work before the hunt. They pack a four-wheel drive vehicle with drone and computer equipment, battery charging stations, generators, fuel, food, camping equipment, tables, chairs and much more. The drive to the fall site can take more than a day, often on rough or nonexistent roads. Anderson says, “You hope you don’t pop a tire.”

After arriving, the team flies its primary drone at an altitude of about 20 meters. Its camera takes an image of the ground once every second, and the scientists download the data every 40 minutes or so when the drone lands to receive fresh batteries. A typical day of flying can net over 10,000 images, which are then divided digitally into 100 million or so smaller sections. Those “tiles”, each 2 meters on a side, are fed into a machine learning algorithm (算法) that has been trained to recognize meteorites based on images of real land rocks which are spray-painted black.

8 . Recent research confirms what our farming ancestors have known for centuries about hedges (树篱). They conserve precious soil by acting as windbreaks and absorbing rainwater that would otherwise wash it from the fields. And hedges store carbon, putting them in the front line of our bi d to tackle the climate crisis.

However, hedges have had a tough time in the poor countryside, with farmers encouraged to tear them down in pursuit of maximum production and larger field s to accommodate ever-larger machinery. What’s more, some hedges have been ignored. If left to their own devices, they’ll eventually become a line of trees. Some hedges each year lose their structures and fail to fulfil the primary duty as a barrier. Around a half of the nation’s hedges have disappeared in the past century.

There are signs that “the tide is turning”. The search for net zero has aroused many organizations’ interest in the humble hedge’s role as a carbon sink. The Climate Change Committee is recommending a 40 percent increase in hedges: an additional 200,000 km. Such recommendations are starting to drive policy. Cash-pressed farmers will be encouraged to create new hedges and improve their management of existing ones under the new Environmental Land Management Schemes, which will replace many of the existing agricultural support payments in coming years. Meanwhile, initiatives such as Close the Gap, led by the Tree Council, is providing funding and support to plug the gaps in existing hedges with new planting. There’s even an app to help time-pressed farmers do a quick survey to spot where their hedges need some help.

This is a good time for hedges. Take some of the most pressing challenges facing the countryside, and indeed, the world as a whole — the climate crisis, soil erosion (侵蚀), insect attack and wider biodiversity loss — and hedges are part of the solution.

9 . Time is running out for coral reefs as the climate gets hotter. So scientists are searching the globe for corals that are better at enduring heat, Now, new research shows how those “super corals” can survive: less roommate drama.

Reefs depend on a crucial partnership between the corals and the algae (海藻) that live in the corals’ tissue, The algae make food for the corals using sunlight and in exchange, get a nice spot to live. But when oceans heat up, that relationship goes bad, and the corals kick the algae out, Without their roommates, corals can die, turning a ghostly white, bleached (白化) color.

Still, some corals seem to resist bleaching better than others, A new study shows that those corals depend on algae that are better at tolerating heat. Researchers hope that pinpointing these abilities will help develop new conservation tools to preserve the world’s reefs as temperatures rise. About 1/4 of all marine life rely on coral reefs in some way, along with half 1 billion people around the world also depend on reefs for their food and livelihoods.

“Heat stress can kill a lot of corals really fast,” says Kate Quigley, a research scientist at James Cook University and the Minderoo Foundation in Australia. “I hope that nature does have some mechanisms to get us through the next few years while we get our act together.”

While the hope is that those algae could also aid in reef conservation in the future, researcher Patrick Buerger says it’s likely that it wouldn’t help all coral species. And even the toughest corals can only endure so much. Currently, the world is on track for just under 3degrees Celsius of warming by 2100, a level that would wipe out nearly all coral reefs.

“The action has to be on climate change,” he says. “This is a short-term solution that might buy some time for corals to adapt. But the main focus has to be on climate. There’s not a silver bullet to the problem.”