"In heat waves, chemicals like formaldehyde and ozone can form more readily in the air, according to researchers driving mobile labs in New York City this week."

"Two vans loaded with precision instruments trundled along the streets of New York and New Jersey in the heat earlier this week, sniffing for toxic chemicals in the air.

They detected spikes in methane, a potent greenhouse gas, most likely from leaks, or from natural-gas-burning buses. They found plumes of nitrous oxide, possibly from wastewater. And all along the ride, they logged elevated levels of ozone, the main ingredient of smog, as well as cancer-causing formaldehyde — both of which form readily in hot weather.

The bottom line: The streets are dotted with pollution hot spots. And the heat makes pollution worse.

“If you want a chemical reaction to go faster, you add heat,” said Peter DeCarlo, an atmospheric air pollution researcher at Johns Hopkins University who’s leading an effort to use the vans to measure emissions along Louisiana’s petrochemicals corridor. “On hotter days, it’s the same idea,” he said."

Hiroko Tabuchi reports for the New York Times June 21, 2024. [2]