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Will air quality anxiety make us rethink the Fourth of July?

Of all the topics I’ve become an expert on in the past month — carbon-fiber submersible hulls; Yevgeny Prigozhin; the cultural evolution of orcas — by far the least useless has been the Air Quality Index.
While I used to have a caveman-like grasp of the AQI scale (red! bad!), multiple “smoke events” in the Midwest and East have since made me hyperaware of what I’m inhaling. Now I’m a person with opinions about the merits and limitations of AirNow vs. Purple Air vs. IQAir. I make observations like “it’s gonna be a hazy one” out loud to myself on the subway platform. A neglected Wirecutter-recommended air purifier, purchased after an apartment fire (long story), has been re-established in my living room.
It is as one newly-minted AQI aficionado to another, then, that I wanted to let you know to prepare for degraded air quality on the Fourth of July. Not because wildfire smoke is blowing back into the United States — though it might be doing that, too — but because nationwide, Independence Day and July 5 are often the highest average particulate pollution days of the year due to fireworks. In fact, The Washington Post has had to caveat its coverage of the smoke over D.C., saying "Thursday was D.C.’s third-highest non-4th of July smoke pollution on record" (emphasis added).
Before you come at me for trying to “cancel the Fourth of July,” understand that I have a solemn respect for our God-given right as Americans to gloat over the British by blowing stuff up. Some of my most cherished childhood memories, in fact, are of contributing to the sulphuric fog that would hang over the unincorporated lake where we’d go to shoot off mortars as kids. (Still hate Piccolo Pete’s, though).
But fireworks also release a lot of PM2.5, tiny particulates that can penetrate deep into our lungs and wreak who-knows-what-kind of havoc on our bodies, and that is also released by wildfires. PM2.5 is, importantly, one of several pollutants factored into the AQI. New owners of air quality monitors, purchased to keep an eye on recent wildfire smoke conditions, might notice readings tick up into the “unhealthy” or “very unhealthy” territory on Tuesday night due to the celebrations.
In particular, the stuff that makes fireworks so pretty — heavy metals like copper, lead, sulfur, aluminum, arsenic, and iron dust — are not exactly things you want to be inhaling. Though recent research on daily mortality and fireworks-related air pollution has been so far inconclusive and is ongoing, one 1975 study found an 113% increase in respiratory illness treatments on the Fourth of July, the New York Post points out.
What that also tells us is that we’ve known about the air pollution from fireworks for years. That there hasn’t been a bigger public expression of concern might depend on a variety of things: that firework smoke pollution decreases rapidly after the 5th so exposure is fairly limited, but also that the fun of fireworks outweighs their (mostly invisible) tolls. It’s also very likely that relatively healthy Americans just haven’t paid that much attention to air quality before.
Now, though, that’s changing.
Interest in air quality began to spike in 2018 — then the largest, deadliest, and most-destructive wildfire season in California history — and grew further in 2020 when smoke turned San Francisco orange, Bloomberg declared “smoke apps [are] the new weather apps,” and Apple added air quality recommendations to the iPhone’s native Weather app. Attention to air quality spread east this spring when New York City broke the national wildfire air pollution record. This week, the Canadian wildfire smoke returned and put more than 100 million Americans — nearly a third of the country, from the midwest to Vermont and as far south as North Carolina — under air quality alerts. In New York, the sky once again took on a sickly yellow-gray look and dramatic red sunsets returned; Midwestern cities had the worst air quality in the world earlier this week. As a result, many Americans are paying closer attention to the AQI than ever before; many others are paying attention for the first time.
A number of cities are reportedly reconsidering their fireworks shows as a result of the latest plume of wildfire smoke. “If [the Fourth of July] was today, we’d cancel,” the mayor of the Cleveland suburb of Solon, Ohio, told Cleveland.com on Wednesday, when the local AQI was around 244. “It is impossible for us to predict what will happen for the holiday celebrations on Monday and Tuesday the Fourth,” New York Governor Kathy Hochul similarly warned her state on Thursday, adding that residents ought to be “very, very vigilant before you plan your outdoor activities.” In Montreal, Canada Day firework displays, scheduled for Saturday night, were preemptively scrapped.
Of course, the irony of all this fuss is that sitting near a firework display has about the same effect as sitting in moderately dense wildfire smoke. I’m not saying either is a brilliant idea; the two compounded, certainly, would be rough on the lungs. But in the great American tradition of being free to make reckless decisions about our own bodies, it’s likely most celebrants this year will have to navigate these kinds of decisions for themselves.
After all, what could be more patriotic than that?
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France’s deadliest heat wave since 2003 killed more than 2,700 people — and possibly as many as 5,700.
More than 5,700 excess deaths were recorded in France during this summer’s record-breaking heat wave, the country’s health agency announced today. That makes the event — which ran, by the official reckoning, from June 17 to July 2 — the country’s deadliest heat wave in more than 20 years.
That’s in line with other estimates we’ve heard. EuroMOMO, a network of European public health agencies that track excess mortality, found that the continent saw more than 10,000 excess deaths during the same period. Roughly 90% of those victims were older than 65, it said. (France’s cohort seems similar: Adults older than 75 made up about two-thirds of the victims, the government said.)
These numbers are staggering — and much larger than some astute Heatmap readers might anticipate. If you read my colleague Jeva Lange’s piece on why it’s so hard to estimate heat deaths last week, she cited a much smaller estimate: Roughly 2,700 died in France during the most recent heat wave. That tally came from Christopher Callahan, an Indiana University scientist who studies climate change’s economic and social costs.
Why is there such a gap between the figures? I emailed Callahan to find out. He shared a few thoughts. First, he uses a different (and theoretically more rigorous) method than the French government: “Our approach uses a statistical relationship between temperature and mortality to explicitly quantify how many additional deaths are associated with a given day’s temperature,” he wrote. “France’s report of excess deaths is just based on how many more people died in late June compared to previous Junes - but we don’t know if those people died because of the heat or some other factor.” (Carbon Brief recently published a Q&A on these varying approaches.)
That might mean his estimate is right, in which case France has misidentified roughly nearly 3,000 deaths. But it could also mean his model, which is trained on data from 2004 to 2019, is “missing something,” he said, like a post-Covid change to public health risk. Last year, Callahan and his colleagues used a similar model to estimate deaths from France’s worst-ever heatwave, a 2003 episode that overwhelmed morgues and killed about 16,000 people. Even 23 years ago, global warming helped make that disaster larger than it needed to be: Some 6,000 of those deaths were due to climate change, their paper found.
Either estimate of the 2026 heat wave, of course, is shattering. As Jeva wrote, even the lower figure would mean the 2026 heat wave killed as many people as died in three years of French homicides. But the divergence in estimates tells us something else too: Even as climate change breaks records and alters our world, we’re never going to quite agree on where it ends and normal randomness begins.
The AI data center boom does not seem close to ending. Google’s parent company, Alphabet, announced its second quarter results this evening, and it beat Wall Street’s expectations, nearly quadrupling its profit on a year-over-year basis. Among the drivers: Its cloud business grew 82% compared to the same quarter last year. (As I’ve written, that rapid growth is helping to turn Alphabet and other hyperscalers into light industrial firms.)
The company’s AI bets seem to be paying off so far — so Google is now planning on spending even more on data centers, energy infrastructure and AI development this year than it once anticipated. It raised its estimates of 2026 capital expenditure to $195 billion to $205 billion, which is above earlier projections and twice as much as it spent in the same category last year. 2027 could be even bigger, it signaled. The company’s shares fell slightly on the news in after-hours trading, but from an energy and climate wonk perspective, the message is clear: For now, the AI demand surge transforming the power sector — and the real economy — continues to chug along.