Scientists Engineer Wood-Based Foam to Keep Buildings Cooler

This May 16, 2021, photo shows window air conditioners in New York.  (AP Photo/Jenny Kane)
This May 16, 2021, photo shows window air conditioners in New York. (AP Photo/Jenny Kane)
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Scientists Engineer Wood-Based Foam to Keep Buildings Cooler

This May 16, 2021, photo shows window air conditioners in New York.  (AP Photo/Jenny Kane)
This May 16, 2021, photo shows window air conditioners in New York. (AP Photo/Jenny Kane)

Summertime is almost here, a time when many people try to beat the heat. But running air conditioners constantly can be expensive and wasteful.

Now, researchers at the Materials Science and Engineering Department (MSE) at Nanjing Tech University have designed a lightweight foam made from wood-based cellulose nanocrystals. According to the study published in the journal Nano Letters on May 18, the new material reflects sunlight and is thermally insulating. They suggest that the material could reduce buildings' cooling energy needs by more than a third.

To generate a cooling material, the researchers connected cellulose nanocrystals together with a silane bridge, before freezing and freeze-drying the material under a vacuum. This process vertically aligned the nanocrystals, making a white, lightweight foam, which reflected 96% of visible light and emitted 92% of absorbed infrared radiation.

When placed over an aluminum foil-lined box sitting outdoors at noon, the material kept the temperature inside the box 16 degrees F cooler than outside of it. Also, the material kept the inside of the box 13 degrees F cooler when the air was humid. As the cellulose-based foam was compressed, its cooling ability decreased, revealing tunable cooling properties.

The team calculated that placing the foam on the roof and exterior walls of a building could reduce its cooling energy needs by an average of 35.4%. Because the wood-based cellulose foam's performance can be tuned depending on weather conditions, the researcher say that the technology could be applied in a wide range of environments



Can Nations Save the Shorebird that Flies 30,000 km a Year?

The Hudsonian godwit (Limosa haemastica) is one of the world's most remarkable travelers, but its population has plunged 95 percent in four decades due to a complex mix of environmental changes across multiple countries. Luke Seitz / Cornell Lab of Ornithology/AFP
The Hudsonian godwit (Limosa haemastica) is one of the world's most remarkable travelers, but its population has plunged 95 percent in four decades due to a complex mix of environmental changes across multiple countries. Luke Seitz / Cornell Lab of Ornithology/AFP
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Can Nations Save the Shorebird that Flies 30,000 km a Year?

The Hudsonian godwit (Limosa haemastica) is one of the world's most remarkable travelers, but its population has plunged 95 percent in four decades due to a complex mix of environmental changes across multiple countries. Luke Seitz / Cornell Lab of Ornithology/AFP
The Hudsonian godwit (Limosa haemastica) is one of the world's most remarkable travelers, but its population has plunged 95 percent in four decades due to a complex mix of environmental changes across multiple countries. Luke Seitz / Cornell Lab of Ornithology/AFP

Chasing an endless summer, one shorebird species undertakes a grueling annual journey from the Arctic to the tip of South America and back -- a feat increasingly fraught with peril.

The Hudsonian godwit (Limosa haemastica) is one of the world's most remarkable travelers, but its population has plunged 95 percent in four decades due to a complex mix of environmental changes across multiple countries, said AFP.

It is one of 42 species proposed for international protection at a meeting of parties to the UN Convention on the Conservation of Migratory Species (CMS) that starts in Brazil on Monday.

Iconic creatures like the snowy owl -- of Harry Potter fame -- striped hyena and hammerhead shark are also on the list deemed in danger of extinction and needing conservation by the countries they pass through.

Migratory birds are facing "rapid and dramatic declines," said Nathan Senner, an ecologist and ornithology professor at the University of Massachusetts Amherst who has studied the Hudsonian godwit for 20 years.

Scientists are still unraveling the mysteries of the shorebird -- which can fly up to 11,000 kilometers (6,800 miles) in one stretch without stopping to eat, drink, or sleep.

And it is only part of the 30,000 kilometers (18,600 miles) that the godwit travels every year from their breeding grounds in the Arctic to Patagonia where they spend the southern summer.

- Disrupted migrations -

In order to do this "epic flight," they need "really predictable, abundant food resources" at every step of the journey, Senner told AFP.

That predictability is crumbling.

In the Arctic, shifting spring timing attributed to climate change has created a mismatch between when chicks hatch and the peak availability of insects they feed on.

One of the puzzles Senner is currently working on is why Hudsonian godwits have begun migrating later by six days than they did a decade ago.

Something "has either disrupted the cues that they use to time their migrations or their ability to successfully and rapidly prepare for the migration," he said.

In southern Chile, a boom in salmon and oyster farming has led to a build-up of infrastructure and the presence of people in the intertidal zones where they feed.

And in the United States, changes in farming practices are making the shallow water wetlands that the godwits rely on rarer and less predictable -- meaning they spend more time looking for a place to stop and feed.

"I think that is emblematic of lots of species, that most species can respond to one kind of change, but not a whole bunch of them all at the same time," said Senner.

- Essential to ecosystems -

"Climate change is taking a heavy toll on species that rely on a 'geological clock' for their survival; many are disappearing," Rodrigo Agostinho, president of Brazil's environmental agency (Ibama), told AFP.

These are some of the issues CMS parties will tackle at their meeting in Brazil's biodiversity-rich Pantanal, one of the world's most important global meetings for wildlife conservation.

These countries are legally obliged to protect species listed as at risk of extinction, conserve and restore their habitats, prevent obstacles to migration and cooperate with other range states.

Nevertheless, among the species listed under CMS, a report released earlier this month showed that 49 percent now have populations that are declining, up from 44 percent two years ago.

Amy Fraenkel, CMS executive secretary, told AFP that most of the species doing worse were birds, such as the Hudsonian godwit.

She said the situation was also "particularly alarming" for fish species, with 97 percent of those listed under the treaty threatened with extinction.

Migratory species "are essential to healthy ecosystems and a healthy planet," playing a key role in pollination, pest control and transporting nutrients, she said.

In a piece of good news, the meeting will propose removing Central Asia's Bactrian deer from its list of animals needing high protection, due to an increase in its population.


Dog Finds Canadian Message in a Bottle on Aberdeenshire Beach

A message in a bottle (Shutterstock) 
A message in a bottle (Shutterstock) 
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Dog Finds Canadian Message in a Bottle on Aberdeenshire Beach

A message in a bottle (Shutterstock) 
A message in a bottle (Shutterstock) 

A message in a bottle dropped from a boat off Canada has been found washed up in the north-east of Scotland, according to BBC.

The short letter, written in French and dated in 2024, was found inside the bottle at St Cyrus in Aberdeenshire.

Having travelled across the Atlantic, it was found by one of Mike Scott's dogs during a beach walk.

The 60-year-old said he was “amazed” by the bottle's journey of about 2,700 miles (4,300km).

The professional photographer from Johnshaven takes his dogs to St Cyrus most days for a walk.

He described the weather as “wild” at the time they discovered the bottle.

“As I was walking, Maggie my dog was sniffing a bottle that was just washing up. It was a really dark glass bottle with a lid and something in it,” he said.

He explained: “I had found a message in a bottle before, but it was just from Dundee, so I was not expecting much. There was a zip bag in it, and a letter in French. I put it in my rucksack and put it on translate when I got home.”

The note - which appeared to be signed 'Annie Chiasson' - said the bottle had been put to sea from a ferry travelling between Prince Edward Island and Iles-de-la-Madeleine in August 2024.

Scott said, “So the small glass bottle has survived two winters at sea, travelling from the east coast of Canada, across the north Atlantic, over the top of Scotland and down into the North Sea for us to find at St Cyrus.”

“The sender was asking to let them know if found,” he said. “We found the woman on Facebook, my wife sent a message, but we have heard nothing back.”

BBC Scotland News has also tried to contact the sender.

Scott said, “It was such a weird thing to find, it's not just our own rubbish that washes up. It's amazing it was not smashed. I do not imagine she thought it would end up in Scotland across the Atlantic.”


America's Official Mammal, the Bison, Gets Bronze Tribute for Country's 250th Birthday

Bison statues cast in bronze are on permanent display outside the Smithsonian's National Museum of Natural History, Friday, March 20, 2026, in Washington. The Washington Monument is in the background. (AP Photo/Rahmat Gul)
Bison statues cast in bronze are on permanent display outside the Smithsonian's National Museum of Natural History, Friday, March 20, 2026, in Washington. The Washington Monument is in the background. (AP Photo/Rahmat Gul)
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America's Official Mammal, the Bison, Gets Bronze Tribute for Country's 250th Birthday

Bison statues cast in bronze are on permanent display outside the Smithsonian's National Museum of Natural History, Friday, March 20, 2026, in Washington. The Washington Monument is in the background. (AP Photo/Rahmat Gul)
Bison statues cast in bronze are on permanent display outside the Smithsonian's National Museum of Natural History, Friday, March 20, 2026, in Washington. The Washington Monument is in the background. (AP Photo/Rahmat Gul)

The national mammal of the United States is getting in on America's 250th birthday celebration.

Three bison statues cast in bronze have taken up a permanent display outside the Smithsonian’s National Museum of Natural History in Washington. The pieces — which are larger than real-life bison — made their public debut in the nation's capital on Friday, The Associated Press reported.

The bison earned its official status as the nation's mammal under a law signed by former President Obama in 2016. Millions of bison once roamed the Great Plains but were nearly driven to extinction in the 1800s.

“It’s a wonderful story of conservation working, it’s a story of people seeing a need and getting behind that to conserve an animal that is specific to North America,” said Gary Staab, a paleoartist who made the statues.

Staab designed and sculpted the statues in Kearney, Missouri, where he works full-time to create sculptures of animals and historical artifacts for museums around the world. For the bison, Staab sculpted the full-size statues in foam and clay before they were cast in bronze and assembled at a foundry in Colorado. The three statues depict a bull, a cow and a calf.

He said it took about four months to complete the sculptures — a time frame he called “lighting fast” given the size of the pieces.

“They really represent a really unbelievably beautiful and unique thing about North America,” Staab said.