The East Coast Has Been Smokier Than the West Coast This Year

One thing New Yorkers could always reliably lord over urban Californians was our air. No, our city isn’t perfect — we manage our trash by piling it on the curb and have this pesky thing called “winter” — but at least in recent years our metro area beat San Francisco, Sacramento, and smoggy Los Angeles when it came to the particulates we inhale.

It brings me no joy to report, then, that this spring, tides have turned. Or at least the winds have. East Coasters have evidently inhaled more smoke than most Californians in 2023 due to a quiet start to the wildfire season out West and an explosive start to the one upwind of us in Alberta, Saskatchewan, and now Nova Scotia.

Here’s what the historic AQI has looked like in New York since late April (the yellow spikes mark smoky days):

The historic air quality graph for New York City in spring 2023.IQAir

And here’s what it’s looked like in Boston:

The historic air quality graph for Boston in spring 2023.IQAir

By comparison, here is San Francisco:

The historic air quality graph for San Francisco in spring 2023.IQAir

And Sacramento (note the AQI scale here has changed on the left to out of 50):

The historic air quality graph for Sacramento in spring 2023.IQAir

Though the air quality in Los Angeles has been significantly worse than the AQI in New York or Boston this spring, the yellow “moderate” AQI columns below overlap with a period of heavy urban pollution, rather than wildfire smoke. The yellow columns on the East Coast AQI charts, by contrast, match periods when wildfire smoke blew in from Canada.

New Yorkers might be surprised to hear they’ve experienced more smoked-tinted sunrises and sunsets this year than Californians, but it checks out: There have been no major (more than 1,000 acres) fires in California yet in 2023. While that might seem unusual, it isn’t; what is unusual are the years like 2021, when the season started in early spring. But 2023 is so far looking to be an average year for California wildfires, which means large burns and regional smoke pollution aren’t expected in the Golden State until late summer and early fall (of course, an El Niño could throw all of this into question).

Meanwhile, in Canada, it is fire season — and it’s been an especially bad one. Almost 5 million acres have already burned, with Alberta on track to have its worst fire year ever. Though smoke from the Canadian fires has blown into a number of northern U.S. states, including Washington and Montana, the jet stream generally carries air east, with some particulate matter making it as far as Boston and New York. (Winds have likewise prevented Canadian wildfire smoke from making it as far southwest as California, hence the unexpected smoke disparity). Over the weekend, a new fire also started in Nova Scotia, causing some 16,000 evacuations around Halifax; the wind has blown much of that smoke southwest, with residents of Connecticut and Massachusetts reporting on Tuesday that they could smell and even taste the smoke.

The smoke from Canada is also, of course, causing the air quality across the East Coast to plunge. This is not in and of itself a rare occurrence: In 2021, smoke from fires in California likewise caused New York City to experience its worst AQI in 15 years.

East Coast residents may nevertheless feel — incorrectly — that they’re isolated from the dangers of wildfires. In truth, roughly three-quarters of smoke-related asthma cases and deaths occur east of the Rocky Mountains, one study found, due to both population density and wind patterns. Another pre-print study by Stanford researchers that was recently referenced by David Wallace-Wells in The New York Times found similarly that 60 percent of the smoke impact from U.S. wildfires occurs in a different state than the one where the fire is actually burning. Separately, a University of Washington study found that people were 1% more likely to die from “nontraumatic” causes like a heart attack or stroke on a day when they were exposed to wildfire smoke — and 2% more likely the day after.

New Yorkers live in the superior coastal city, but we shouldn’t get too smug about our air. Thinking we’re somehow immune to the West’s smoke problems is patently false and getting falser. Besides, why should Angelenos get to have all the fun? It’s only fair that we get to obsess over our PurpleAir score, too.

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