West Coast wildfire smoke expected to reach New York more often, study predicts

Smoke from western wildfires turned New York skies hazy at times this summer, and the East Coast's air pollution will probably worsen in coming years as climate change spawns more and more of the blazes, a study predicts.

The new study, which focuses on July 2021, says wildfire smoke from southern Canada reached New York State within four to eight days, with significant amounts of tiny smoke particles destructive to lungs in the air reaching the Earth’s surface twice that month.

“Some summers will be bad, some won’t,” said Bhupal Shrestha, study author and senior research support specialist for the New York State Mesonet at the University at Albany. “Because of rising temperatures and lower humidity, all these wildfires are increasing. … This is expected and will continue into the future.” The Mesonet is a network of weather stations.

The two times wildfire smoke infiltrated downstate New York were July 19 to 21 in 2021 and July 25 to 27 in 2021.

In the summer of 2022, the lung-damaging fine particles mainly stayed aloft, meteorologists said. “I think this year the wildfire smoke was not in as high a concentration compared to last year,” said Shrestha.

One reason the New York area got off fairly lightly this summer — unlike some West Coast cities where numerous air quality warnings were issued — is that California’s wildfires, though still deeply destructive, only burnt 362,232 acres, according to the California Department of Forestry and Fire Protection.

That is about one-seventh of the 2,569,386 acres scorched in the summer of 2021, and around one-twelfth the 4,304,279 acres destroyed in 2020, it says.

“California has been below average this year, and so has much of the West, aside from a few areas,” said Jim Wallmann, a meteorologist at the National Interagency Fire Center in Boise.

Whether the fine particles from smoke — considered especially hazardous because they can travel deep into the lungs when inhaled — descend low enough to foul the air people breathe naturally hinges in part on upper-level winds, including the jet stream.

“For air quality, it wasn’t a problem this year,” for the Northeast, said David Robinson, New Jersey's state climatologist and a distinguished professor at Rutgers University. “There were several instances when the smoke came through, but it was very high in the atmosphere, so it did not impact the ground air quality,” he said.

“So the skies got more milky, back in August … you couldn’t smell it, you wouldn’t be breathing it,” because it was too high up in the atmosphere.

Spring rains also helped suppress the latest fire season.

“Before the summer hit, it stayed cool and wet over much of the West,” Wallmann said. “What that did, it seems to have compressed our fire season, so it delayed it into August, if not late August,” though there were a few notable exceptions.

In contrast, the West Coast summer of 2021 was preceded by a dry winter and spring, Wallman said, so blazes begun by lightning strikes were “more likely to go large.” 

In the summer of 2021, the New York region’s weather was partly dominated by a massive ridge, or a high-pressure pattern, whose falling air could have helped bring those small particles down to Earth.

“You want that perfect setup,” said Jase Berhhardt, an associate professor in the Department of Geology, Environment and Sustainability at Hofstra University. “You want a high-pressure (system) that leads to clear and calm conditions,” he said, which means the particles “kind of get stuck in the atmosphere,” instead of being washed out by rain, for example.

Wildfires, of course, remain highly unpredictable, and in at least some instances, impossible to prevent, so they can jeopardize progress toward cleaner air, the study said:

“The increasing frequency and intensity of wildfires due to climate change are projected to enhance these emissions even more in the near future, potentially offsetting nationwide efforts to regulate air pollution.”