Warming Trends: Cacophonous Reefs, Vertical Gardens and an Advent Calendar Filled With Tiny Climate Protesters

A column highlighting climate-related studies, innovations, books, cultural events and other developments from the global warming frontier.

A researcher deploys a hydrophone, an underwater listening device, on a coral reef in Sulawesi, Indonesia. Credit: Tim Lamont/University of Exeter
A researcher deploys a hydrophone, an underwater listening device, on a coral reef in Sulawesi, Indonesia. Credit: Tim Lamont/University of Exeter

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A Noisy Reef Is a Healthy Reef

A healthy coral reef is full of sounds. Fish whoop, purr and grunt while shrimp snap. But around parts of the reef where coral has been violently destroyed by dynamite fishing, the waters are silent. 

Researchers at the University of Exeter in the United Kingdom sought to find out whether reefs in Indonesia that were restored after being destroyed by dynamite had recovered their sound, as well as their healthy appearance. The investigators set up underwater microphones to monitor the soundscape on healthy, degraded and restored reefs. The diversity of sounds was similar at healthy and restored reefs, they reported this week in the Journal of Applied Ecology.

“There are all sorts of these noises and sounds and buzzes and pops and trills and croaks and groans,” said lead author Tim Lamont, a marine biologist at the University of Exeter. “That to us is an indication that a lot of the animals responsible for those sounds have come back to the restored reef and have colonized and set up shop.”


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Fish and other marine creatures use sounds for hunting, mating, fighting and communicating every day, Lamont said. And by studying the sounds of a coral reef, he said, researchers can hear all kinds of animals that can’t be seen, whether they’re camouflaged, nocturnal or just well hidden. 

Lamont said he felt an “almost childlike joy of discovering these bizarre new noises that a fish makes and we have never heard before,” he said, “and the thrill of swimming along listening to something that maybe nobody’s heard before.”


Walls of Plants to Keep You Warm

Could a wall covered in plants work as an effective insulator for buildings? New research shows how powerful vertical gardens can be in keeping indoor temperatures comfortable.

Heat loss from an exterior wall covered with plants in a half-century-old building was 31 percent less than a wall without plants in the same building, according to the new study, from the University of Plymouth in the United Kingdom.

University of Plymouth Sustainability Hub showing external green wall in full bloom. Photo Courtesy of Alan Williams
University of Plymouth Sustainability Hub showing external green wall in full bloom. Photo Courtesy of Alan Williams

Many buildings in the U.K. are constructed with walls made of two layers of stone, with a hollow center. To improve heat retention, the cavity can be filled with insulation like plastic-based polystyrene, said Matthew Fox, an sustainable architecture researcher and an author on the study, but putting a green wall on the outside of the building could have the same effect. 

“That also brings with it all the added benefits. You’ve got biodiversity, you’ve got improved visual amenity; research has found that people feel happier about their environment or about their buildings if they are covered in plants,” he said. “It’s that basic primeval connection with nature that you get, and you don’t get that with polystyrene, oddly enough.”

The researchers said they hoped more buildings could add green walls to prevent heat loss, which would reduce heating costs and cut greenhouse gas emissions from energy used to power climate control systems in buildings. Space heating accounts for more than 60 percent of the energy use of buildings in the U.K., the study noted, and buildings account for 17 percent of the country’s greenhouse gas emissions. 

Plus, green walls can shade buildings to help keep them cool in summer; block gusty winds; slow the flow of stormwater after big rain events, which are becoming more common in the U.K. as the climate warms; and provide resources for declining pollinators and other animals threatened by habitat loss, the researchers said. 

“We know our biodiversity is already pretty threatened in the U.K. and globally, so I think these urban areas potentially could become biodiversity deserts,” said environmental scientist and study author Thomas Murphy. “Having this green infrastructure can really support that.”


Want to Measure Air Pollution? Look at Your Watch

Real-time air pollution monitors could someday be inside smartwatches, allowing users to follow paths through areas with cleaner air. The mini-monitors could also map pollution hotspots in cities and give researchers precise, hyperlocal data to study pollution exposure and health effects. 

That’s the hope of researchers at three Michigan universities who have received a $2.7 million, five year National Institutes of Health grant to create a miniature air pollution monitor that is portable and potentially wearable. 

“By making a wearable device that is collecting data in real time, and making that wearable so that it can be carried by people as they move around the various micro environments that they experience each day, that gives us spatial aspects,” said Andrew Mason, a professor at Michigan State University’s College of Engineering. “This is something that can’t be done with current technologies.”

Current air pollution monitors are usually large and not easily portable. But with this project, the researchers hope to get the device down to the size of a hockey puck, or even a wristwatch. 

These devices also would be able to collect more precise information about the air particles. Mason said the device will be able to distinguish particles by chemical composition, like whether a particle is a toxic heavy metal, and by size, hopefully measuring particles as small as 20 nanometers, or one-3,000th the width of a human hair. 

This kind of precision would open the door for new research on these incredibly small particles and what their health effects are, said Tim Dvonch, an associate professor of environmental health sciences at the University of Michigan’s School of Public Health. Current air pollution laws regulate particles smaller than 2,500 nanometers, or 2.5 microns. 

“It’s quite possible that there needs to be a standard for an even smaller particle size classification,” Dvonch said. “But the research data on exposure and health doesn’t exist, because we don’t have the tools to properly assess it. And so this type of device would provide one of those tools.”


‘Waste to Wood to New Trees’

Each year, 36 million trees fall or are cut down in cities across the United States. Most of them are disposed of in landfills or chipped into quickly decomposing mulch. But a pair of entrepreneurs is creating an economy for these wasted trees, and giving them a more climate friendly second life. 

Cambium Carbon, a company started by Ben Christensen and Marisa Repka, finds trees from suppliers, like city governments, and connects them with buyers, like architects and woodworkers, who want to use the trees for projects such as building furniture, flooring or any other wood product. 

“There’s sort of a broken connection between supply and demand there,” Christensen said. “So what we’re really focused on is enabling that connection in a way that really prioritizes reinvestment in the type of people-first climate solutions that we want.”

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The funds raised through selling the wood that otherwise would have been wasted are put back into tree planting programs to maintain the urban tree canopy, which sequesters carbon and provides health benefits to the community. 

We like to think about this as waste, to wood, to new trees,” Repka said. “When a tree falls in the city, it’s being processed into a higher value good. The sale of that product is then reinvested in new tree planting and maintenance. So it’s kind of bringing that full value full circle.”

The company is currently working with 130 suppliers and eight city governments, including New York, Philadelphia and Denver. They recently received the J.M.K. Innovation Prize, which awards $175,000 over three years, which Christensen and Repka say will help Cambium Carbon operate in a more systematic, community-focused way.

“One of our core values is ‘listen first,’” Christensen said. “That’s something that this funding is going to really allow us to do, is to make sure that we are working in communities in a way that supports them.”


Tiny Climate Protesters Infiltrate Lloyd’s of London

A group of climate activist parents has sent a fleet of miniature protesters into the halls of Lloyd’s of London, in a bid to convince the global insurance market to speed up its move away from insuring fossil fuel projects.

The inch-tall protesters are part of an intricate advent calendar scene that was created by activists with Mothers Rise Up and Parents for Future UK, and delivered to Lloyd’s of London chairman Bruce Carnegie-Brown at the end of November. Each day from Dec. 1 through Christmas Day, Carnegie-Brown can open a box and find new pieces to add to the overall scene. 

The calendar scene shows a cricket match (a sport of which Carnegie-Brown is famously a fan). Each day, new pieces are added to the scene, including piles of coal, trees on fire, cricketers suffering from rising heat and figurines holding placards demanding an end to fossil fuels. Mothers Rise Up is revealing the additions to the scene each day on their Twitter account

“We’re appealing to Bruce,” said Chryso Chellun, a mother and artist who created the advent calendar. “He’s a dad, and we’re basically going, ‘Hey, Dad, fellow parent, this is it. We’re just talking to you. And we’re asking very simple, basic things about our children’s security.”

The parent groups are asking Lloyd’s to stop insuring fossil fuel projects and mandate a similar withdrawal across its marketplace. Currently, the market and corporation plan to have net-zero emissions by 2050, and will halt new insurance for coal-fired power plants, oil sands and Arctic energy exploration on Jan. 1, 2022.

Lloyd’s did not respond to requests for comment, but Carnegie-Brown did respond to Mothers Rise Up and Parents for Future UK on Twitter, saying he is following along with the advent calendar display. 

“We’re so pleased he’s listening,” said Maya Mailer, a climate organizer with Mothers Rise Up. “And we want to continue that dialogue. But we’re not complacent. The proof is going to be in the deeds, and the action that he takes and that Lloyd’s as a marketplace takes.”