Canada’s buildings have an emissions problem. Could fish skin provide an answer? | CBC News

Canada’s buildings have an emissions problem. Could fish skin provide an answer? | CBC News

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This week:

  • Canada’s buildings have an emissions problem. Could fish skin provide an answer?
  • Pope Francis demands more action on climate change
  • Montreal building more sponge parks, sidewalks to soak up heavy rainfall

Canada’s buildings have an emissions problem. Could fish skin provide an answer?

A close-up look at squid skin.

This image is a close-up look at how a squid spreads and contracts sacs filled with pigments along its skin to change colour. (Nature Communications,

Given that building emissions from heating, cooling and lighting account for 18 per cent of Canada’s greenhouse gas (GHG) emissions, many researchers are on the lookout for solutions.

“We spend most of our time thinking about how to keep humans comfortable indoors. And right now, the way we do it is with air conditioners and furnaces and electric lights,” said Raphael Kay, a research fellow at the Aizenberg Biomineralization and Biomimetics Lab at Harvard University.

But Kay and his research team are approaching the problem of regulating the temperature of residential and commercial spaces in a novel way — by taking inspiration from fish.

“The hypothesis with our research is that buildings are not actually that different from biological organisms. And biological organisms control their climate mostly at their skin. And so the research output in our case is actually buildings with veins,” Kay told What On Earth host Laura Lynch.

The idea of a building with veins came to Kay during his master’s degree at the University of Toronto, where he studied how marine organisms like squid and krill release pigmented fluids in their bodies to change the opacity of their skin to regulate exposure to heat and light. (The image above is a close-up look at how a squid spreads and contracts sacs filled with pigments along its skin to change colour.) This led Kay to develop fluids of similar composition, with water, vegetable oils and different pigments, to be dispersed throughout the outer body of a building.  

“It’s not easy to have something appear in an organism. It has to go through millions and millions of evolutionary cycles for it to be considered good enough to stand the test of time,” Kay said. “If all these organisms are using this approach, I have yet to come up with a reason why [we] can’t find a way to do this in an economical way.”

He said there are “a lot of ways” this fundamental concept could be applied. “We can make brand new windows with the system. This could be sort of a retrofit layer that you add to your window. This could go in walls. This could go on roofs.”

He explained the concept specifically for windows. “You can imagine in those windows you have a bunch of tiny voids,” Kay said. “They might be as thick as your index finger. You could call that a channel. And so you can imagine a bunch of channels that are hollow within a window and we can move different liquids or gases within those channels at different times.”

Kay admits the idea of inserting liquids into windows to control heat transfer isn’t new. Research teams in the United Kingdom, Europe and Asia have been testing this technology to heat and cool homes. But Kay insists his team is pioneering the concept of not just controlling heat but also sunlight.

He says that the liquid composition in the “channels” can filter out invisible heat but maintain the illumination. As a result, a person could use a combination of overlapping channels to dim the space or redirect light to certain parts of the room.

Kay believes these building skins will not just be more economical but will also save energy compared to conventional mechanical approaches like automatic blinds or air conditioning.

The next step for Kay’s research is to implement testers in university buildings in the next one to two years. Afterwards, he wants to see this go beyond the laboratory, beyond universities and into the market as a climate-friendly and energy-efficient solution to Canada’s building emissions problem. 

“We’re not using toxic materials. We’re not using rare earth metals. It’s inexpensive, it’s sustainable and it’s scalable. So I do see a future where we kind of have buildings with veins.”

Dannielle Piper

Old issues of What on Earth? are here. The CBC News climate page is here. 

Check out our radio show and podcast. This week, we take you on a hunt for geothermal energy under ancient volcanoes in British Columbia. What On Earth airs on Sundays at 11 a.m. ET, 11:30 a.m. in Newfoundland and Labrador. Subscribe on your favourite podcast app or hear it on demand at CBC Listen.

Watch the CBC video series Planet Wonder featuring our colleague Johanna Wagstaffe here.

Reader feedback

In response to a graph in last week’s issue comparing the emissions reductions in G7 countries since 1990, Karel Ley wrote:

“I am ashamed of Canada’s poor record for emissions rising instead of lessening.”

Tom Hann:

“While the graph of the G7 emissions since 1990 shows reducing GHG emissions within the countries, it does not reflect the global impact of these countries on the level of carbon dioxide in the atmosphere. These countries are global traders. International emissions from their trading are not included nor attributed to the country. For example, Canada is a global exporter of fossil fuels (coal, oil, gas)…. If G7 countries incorporated all these international emissions due to their global trading, a more accurate assessment of their impact on the atmosphere could be presented.”

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The Big Picture: The Pope weighs in on climate change (again)

Pope Francis is deeply concerned about climate change. We know this because he wrote an encyclical (or papal letter) about it in 2015 (entitled Laudato Si’, or Praise Be to You). In it, he stated that the science is clear on what is happening and that we must pursue solutions to reduce our environmental footprint. “The urgent challenge to protect our common home includes a concern to bring the whole human family together to seek a sustainable and integral development, for we know that things can change,” he wrote. 

This week, Francis published an update that basically said: We must do better. 

Reading more like a scientific paper than a papal letter, this document (entitled Laudate Deum, or Praise God) does not mince words. Francis writes about the environmental harms we have already witnessed, and points out that the poor and most vulnerable continue to bear the brunt of the crisis. In a particularly dire section, Francis warned, “We are now unable to halt the enormous damage we have caused. We barely have time to prevent even more tragic damage.”

While the paper excoriates political and corporate interests for their unwillingness to take stronger action to protect the planet, Francis singles out the U.S. for its high per capita emissions, stating bluntly that “a broad change in the irresponsible lifestyle connected with the Western model would have a significant long-term impact” in healing Earth.

The document was released as the Vatican gathers Catholic leaders from around the world in a three-week closed-door meeting, known as a synod. But it was also meant to influence negotiations at COP28, the next UN climate summit, in Dubai beginning Nov. 30.

The Pope is shown in a wheelchair wearing white papal garments and cap.

Pope Francis leads a mass to open the Synod of Bishops in St Peter’s Square at the Vatican, October 4, 2023. (Guglielmo Mangiapane/Reuters)

Hot and bothered: Provocative ideas from around the web

Montreal building more sponge parks, sidewalks to soak up heavy rainfall

Water flows out of a splash pad into a small creek.

A garden and bed of rocks next to the splash pad at Dickie Moore Park act as a drain. (Verity Stevenson/CBC)

Montreal is planning to build more urban sponge infrastructure to protect against future flood waters brought on by climate change. 

The announcement Tuesday came as Montreal once again found itself drying out after heavy rainfall pummelled the city in the early morning. 

By 2025, Montreal plans to build 30 sponge parks and 400 more sponge sidewalks — that is, green spaces that use plant-based structures to naturally absorb excess rainfall instead of draining the water directly into neighbourhood sewers.

The spaces would add to the seven sponge parks and 800 sponge sidewalks built since 2022, according to the city.

“The impact of heavy rainfall can be reduced by redirecting water to the river, retaining it until the sewer system is available or gradually releasing it through the ground,” the release reads.

The city says it plans to install at least enough green drainage infrastructure to retain the equivalent of three Olympic swimming pools’ worth of water. 

More than 1,500 international climate change adaptation specialists are meeting in Montreal this week at the Adaptation Futures conference to discuss best practices in responding to the challenges posed by climate change.

Speaking at the event, Montreal Mayor Valérie Plante said sponge infrastructure is “no magic wand,” but one action among others — like renovating sewer systems — that need to be taken to mitigate the effects of climate change. 

“We started putting sponge sidewalks in 10 years ago in the Plateau and Rosemont–La Petite-Patrie [neighbourhoods], and now we see everyone wants one,” she said, pointing out that some areas, like Centre-Sud in the lower part of the city, are particularly at risk.

However, boroughs wanting sponge parks will have to meet the city’s standards before they get the green light. 

“We’re adding the criteria of adaptation to climate change for renovating certain parks,” said Plante. 

Marie-Andrée Mauger, the executive committee member responsible for the environment and ecological transition, said the plan is to bring sponge parks to all 19 city boroughs, but that 12 boroughs are in their sights as especially prone to above-ground flooding. 

The project will be funded by the $117-million agreement with the Quebec government as part of its green economy plan. 

Alain Bourque, executive director of Ouranos, Quebec’s climatology and climate change innovation hub, said building more water-retention infrastructure is a step in the right direction, as Montreal receives more frequent and intense rainfall. 

“It’s not necessarily the best approach to reconstruct all of the sewer systems in Montreal, and it’s almost impossible,” said Bourque. “So you have to act on the surface and find ways that water infiltrates elsewhere than in the sewer systems that are unable to cope with those thunderstorms.”

Joe Bongiorno

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