Sign In or Create an Account.

By continuing, you agree to the Terms of Service and acknowledge our Privacy Policy

Climate

How Many People Will This Smoke Kill?

Calculating smoke deaths is tricky but important.

Smoke and tombstones.
Heatmap Illustration/Getty Images

I went for a walk on Wednesday. I intended only to go as far as the first intersection — just to get a quick glimpse of how my New York neighborhood has been transformed by the smoke — but each block revealed itself to be stranger and yellower than the last. Mesermized and horrified, my “just stepping out” stretched into a longer walk as I wandered further and further away from the relative safety of the indoors, where my air purifier was on full blast.

By the time I returned home, the stupidity of my decision had struck me — physically. My throat burned and my voice was hoarse; my head pounded; and my eyes were goopy from the smoke. I’d inhaled something — millions of somethings — that my body was vehemently rejecting. How bad, I wondered in a hypochondriacal panic, was my mistake?

It is almost certain that this smoke will kill people. Many will be elderly or people with pre-existing serious health conditions; some of them may be unborn; some may be people who labor outside. But what we do know is that smoke this bad and that lasts for this long is deadly. One widely cited study by 70 international scientists found that short-term exposure to wildfire smoke causes around 3,193 deaths in the U.S. per year (“short-term” means just three days or less; other studies of short-term wildfire deaths found mortality slightly lower) and this week is already a top-three wildfire pollution event of all time for the nation.

Get one great climate story in your inbox every day:

* indicates required

  • Wildfire smoke is particularly scary because it contains teeny tiny particles called PM2.5 that are small enough to enter our lungs and even our bloodstreams. PM2.5 particles are present at some level in every urban environment but wildfire-related PM2.5 is believed to be much more toxic than other normal “ambient” particles because of all the yucky things that burn up in fires.

    The link between elevated PM2.5 particle concentrations and increased mortality can be dramatic. The aforementioned international study on wildfire-related PM2.5 and daily mortality found that “all-cause mortality” — that is, deaths that aren’t accidents — increases by 1.9%, cardiovascular mortality by 1.7%, and respiratory mortality by 1.9% with every bump of 10 micrograms of pollutant per one cubic meter of air. If New York’s PM2.5 concentration averages, say, 75 micrograms over three days this week (the concentration roughly expected for an average AQI of 150), that would mean people of all ages are 12% more likely to die than they otherwise would be.

    To be clear, this doesn’t mean there is a 12% chance you will die this week, but rather that the odds of you dying are 12% higher than they are on an average given day. A young healthy person isn’t likely to die of non-accidental causes on a random normal day, so the danger of wildfire smoke exposure killing you tomorrow is still wildly low. But those numbers go up if you’re elderly or have a heart or respiratory condition to begin with; asthma hospitalizations also, naturally, spike during smoke events.

    Put another way, wildfire smoke is an exacerbating factor of serious health conditions. In one study, the risk of dying of a heart attack in the five days after exposure to significant wildfire smoke was elevated by 6.3%; by another, the risk of having a stroke jumps 22% following smoke exposure. These differences are not insignificant; it means there will be people who die from heart attacks or strokes who might not have if the air had otherwise been clear.

    But of course, these projections are all speculative, which is why figuring out a death toll for the 2023 smoke event will be a tricky and delicate thing to do. No single death can be blamed just on “smoke.” Researchers can use the established link between elevated PM2.5 levels and higher mortality rates to do back-of-the-envelope estimates of short-term deaths — it’s how University of Washington researchers projected about 200 smoke-related deaths immediately after fires in the state in 2020 — but crunching the numbers on excess deaths takes patience and time and remains inexact. A study that identified 133 excess cardiorespiratory-related deaths caused by wildfire-smoke exposure during the 2003 southern California fire season took nearly a decade to make it into print.

    Short-term deaths, of course, are not the whole story either. One of the major concerns about wildfire smoke is what exposure does in the long term — hour after hour, week after week, and season after season. The East Coast had never needed to worry about that sort of prolonged exposure before. But perhaps now it might.

    It may be months yet before we know how bad this smoke event was for the East, and years before we can say with much, if any, certainty. My smoky walk outside probably won’t kill me and, good news, yours probably won’t, either. But “probably” is more than I’d personally like to chance for a few yellowish pictures. Be smart. No poison is always better than “some.”

    Green
    Jeva Lange profile image

    Jeva Lange

    Jeva is a founding staff writer at Heatmap. Her writing has also appeared in The Week, where she formerly served as executive editor and culture critic, as well as in The New York Daily News, Vice, and Gothamist, among others. Jeva lives in New York City. Read More

    Read More
    Podcast

    The EPA’s Carbon Crackdown Is Finally Here

    Inside a special edition of Shift Key.

    EPA Headquarters.
    Heatmap Illustration/Getty Images

    One of the most important pieces of the Biden administration’s climate policy has arrived: On Thursday, the Environmental Protection Agency issued new rules restricting climate pollution from coal-fired plants and natural gas plants that haven’t been built yet. The rules will eliminate more than a billion tons of greenhouse gas pollution by the middle of the century.

    They are the long-awaited “stick” in the Biden administration’s carrots-and-sticks climate policy. So how do the rules work? Why do they emphasize carbon capture so much? And is this the end of coal in America? On this special episode of Shift Key, Rob and Jesse dig into the regulations and why they matter to American climate policy. Shift Key is hosted by Robinson Meyer is founding executive editor of Heatmap, and Jesse Jenkins is a professor of energy systems engineering at Princeton University.

    Keep reading...Show less
    Green
    Economy

    Can Biden Ditch Coal Without Killing Coal Country?

    The end has been coming for a while. With the EPA’s new power plant emissions rules, though, it’s gotten a lot closer.

    President Biden standing on coal.
    Heatmap Illustration/Getty Images

    There’s no question that coal is on its way out in the U.S. In 2001, coal-fired power plants generated about 50% of U.S. electricity. Last year, they were down to about 15%.

    On Thursday, however, the Biden administration arguably delivered a death blow. New carbon emission limits for coal plants establish a clear timeline by which America’s remaining coal generators must either invest in costly carbon capture equipment or close. With many of these plants already struggling to compete with cheaper renewables and natural gas, it’s not likely to be much of a choice. If the rule survives legal challenges, the nation’s coal fleet could be extinct by 2039.

    Keep reading...Show less
    Blue
    Climate

    AM Briefing: A Verdict on Dubai’s Deluge

    On a new World Weather Attribution report, falling battery prices, and another energy milestone for California.

    Briefing image.
    Biden’s Plan to Jumpstart Offshore Wind
    Heatmap Illustration/Getty Images

    Current conditions: Flash floods killed at least 155 people in Tanzania • Dry conditions are spawning dust devils in western Canada • Ongoing thunderstorms are set to pummel the central U.S. with hail and possible sporadic tornadoes through the weekend.

    THE TOP FIVE

    1. Climate change worsened Dubai flooding

    Rising global temperatures due to carbon dioxide buildup in the atmosphere exacerbated the deadly flooding in Dubai earlier this month, scientists at the international research initiative World Weather Attribution concluded. Much of the United Arab Emirates lacks drainage infrastructure because rain there is so infrequent, and the unrelenting downpour that inundated the country on April 14 and 15 — toppling its 24-hour rainfall record — came on the heels of a stormy March. The latest report from the Intergovernmental Panel on Climate Change determined that bouts of intense rainfall are likely to become more common in the Arabian Peninsula.

    Keep reading...Show less