What’s at stake
Climate change affects wildlife, property values, health and safety, agriculture, and the quality of urban life. Communities are already adapting to heat, drought, and floods. Can science bring us solutions?
More efficient plants
The increasing stress of heat and drought is hard on crops. Scientists at Michigan State University are studying photosynthesis to try to make it more efficient. A leaf converts only about 1 percent of the sun’s light into usable energy because of “mistakes” during photosynthesis. The enzyme that is supposed to capture CO2 molecules for photosynthesis often captures oxygen instead, according to Berkley Walker, a plant biologist at Michigan State. A new method for studying photosynthesis, developed in Walker’s lab, was recently published in Nature Plants. Understanding the inner workings of photosynthesis could lead to hardier crop plants – but scientists also need to look for unintended consequences of altering the plant metabolism.
Cooling stations for fish
Cold-water fish like trout and salmon gasp for air in warming streams and rivers, even in Canada. Warm water holds less oxygen, making it hard for fish to breathe. When water temperatures soar into the 80s, it can be fatal for fish. But new methods may help cold-water fish survive. While some scientists are trying to breed heat-resistant fish, others are finding ways to cool rivers, at least temporarily. Kathryn Smith, a civil engineer and PhD candidate at Dalhousie University in Nova Scotia, pumped cold water into the Wrights River to find out if it helped; it did. The plume of chilly well water attracted hundreds of fish, including Atlantic salmon and brown trout. It was especially helpful for juvenile fish. Concerned about the energy cost of pumping, the engineers also tried diverting part of the river through an underground channel, letting the soil and shade cool the water. When the water re-entered the river, it lowered the temperature only a few degrees, but the earth-cooled water also attracted fish.
Insuring people in floodplains
Heavier rainfall events and rising sea levels mean more people are in harm’s way from flooding. It’s ruinously expensive for the government to keep underwriting repairs and buyouts, and the average homeowner without flood insurance only collects a few thousand dollars from the federal government after a flood, seldom enough to cover the actual damage. Even worse, some people aren’t aware that their properties are in danger. Several states lack mandatory flood risk disclosures for real estate transactions, leaving home buyers and renters in the dark about the risks when they make their housing decisions, according to Vermont Public Radio. A new report by the Technical Mapping Advisory Council shows that about 19 million U.S. properties are at high risk for flooding, many more than previous government estimates of 8.5 million. The solution? The federal advisory panel that produced the report recommends that homeowners in those high-risk areas should be required to purchase flood insurance. The recommendation is controversial, as it would be expensive for homeowners to buy insurance. But it could be better for them in the long run than walking the flood tightrope without a net.
Building cooler cities
An article in Grist by Jake Bittle & Naveena Sadasivam outlined several ways to combat the urban heat island effect and make cities more comfortable in summer.
Shaded structures, such as bus stops
Planting trees, which can lower the ambient temperature by as much as 9 degrees Fahrenheit
Misting machines in public spaces
Cool pavements that reflect energy rather than absorb it
Tall buildings that cast shade
Reflective glass (but not pointed at the streets)
Green walls covered with foliage
Opening the ground floor of buildings for greater airflow
In addition to the solutions presented in Grist, a paper in the Annual Review of Environment and Resources in 2015 found that green roofs, densely planted with vegetation, are effective and cost-effective at lowering urban temperatures. Green roofs also prevent runoff onto the streets, reducing flooding. Angel Hsu, on the Public Policy faculty at the University of North Carolina at Chapel Hill, said that buildings with green roofs average 15% savings on cooling bills, speaking at a Knowable webinar in October 2022 on redesigning cities for extreme heat.
Phoenix, one of the nation’s hottest cities, is experimenting with a purpose-built, car-free suburb called Culdesac Tempe. Car engines produce a vast amount of heat, and reducing reliance on them makes neighborhoods cooler. An article in The New York Times covered this purpose-built neighborhood’s pros and cons. According to the story by Conor Dougherty, the 17-acre mixed-use development will feature “761 apartments, 16,000 square feet of retail, 1,000 residents — and exactly zero places for them to park.” Mass transit clearly plays an essential role in making this possible.
The Washington Post ran a simulation in 2022 of a city called “Meltsville” to show how extreme heat could affect urban infrastructure. According to the article, most of our infrastructure was built to handle the climate as it was in the past, not what it is now. Problems the city’s fictitious residents experienced included strain on the power grid, gooey airport runways and roads, and bridge damage as steel and asphalt expanded. And as anybody knows who has encountered a traffic jam, it doesn’t take much to mess up our transportation system. The simulation showed the importance of features like cool pavements and shade for beating the heat. The future is here, now.