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

    You’re out of free articles.

    Subscribe today to experience Heatmap’s expert analysis 
of climate change, clean energy, and sustainability.
    To continue reading
    Create a free account or sign in to unlock more free articles.
    or
    Please enter an email address
    By continuing, you agree to the Terms of Service and acknowledge our Privacy Policy
    Electric Vehicles

    AM Briefing: Carmakers Get a Break

    On exemptions, lots of new EVs, and Cyclone Alfred

    Automakers Have One Month to Prepare for Trump’s Tariffs
    Heatmap Illustration/Getty Images

    Current conditions: A smattering of rainfall did little to contain a massive wildfire raging in Japan • Indonesia is using cloud seeding to try to stop torrential rains that have displaced thousands • At least 22 tornadoes have been confirmed this week across southern states.

    THE TOP FIVE

    1. Trump delays new tariffs for automakers

    The Trump administration said yesterday that automakers will be exempt from the new 25% tariffs on imports from Mexico and Canada – but just for a month. The announcement followed a meeting between administration officials and the heads of Stellantis, GM, and Ford – oh, to be a fly on the wall. As Heatmap’s Robinson Meyer explained, the tariffs are expected to spike new car prices by $4,000 to $10,000, and could hit internal combustion cars even worse than EVs, and prompt layoffs at Ford and GM. “At the request of the companies associated with [the United States-Mexico-Canada Agreement], the president is giving them an exemption for one month so they are not at an economic disadvantage,” Trump said in a statement. Stellantis thanked Trump for the reprieve and said the company “share[s] the president’s objective to build more American cars and create lasting American jobs.” Around 40% of Stellantis cars currently sold in the U.S. are imported from Canada and Mexico.

    Keep reading...Show less
    Yellow
    Politics

    AM Briefing: Trump’s Big Speech

    On boasts and brags, clean power installations, and dirty air

    What Trump Said During His Speech to Congress
    Heatmap Illustration/Getty Images

    Current conditions: Strong winds helped spark dozens of fires across parched Texas • India’s Himalayan state of Uttarakhand experienced a 600% rise in precipitation over 24 hours, which triggered a deadly avalanche • The world’s biggest iceberg, which has been drifting across the Southern Ocean for 5 years, has run aground.

    THE TOP FIVE

    1. What Trump said during his speech to Congress

    President Trump addressed Congress last night in a wide-ranging speech boasting about the actions taken during his first five weeks in office. There were some familiar themes: He claimed to have “ended all of [former President] Biden’s environmental restrictions” (false) and the “insane electric vehicle mandate” (also false — no such thing has ever existed), and bragged about withdrawing from the Paris climate agreement (true). He also doubled down on his plan to boost U.S. fossil fuel production while spouting false statements about the Biden administration’s energy policies, and suggested that Japan and South Korea want to team up with the U.S. to build a “gigantic” natural gas pipeline in Alaska.

    Keep reading...Show less
    Yellow
    Climate

    Why the South Is America’s Newest Tinderbox

    A conversation with Resources for the Future’s David Wear on the fires in the Carolinas and how the political environment could affect the future of forecasting.

    Firefighters.
    Heatmap Illustration/Getty Images

    The Wikipedia article for “wildfire” has 22 photographs, including those of incidents in Arizona, Utah, Washington, and California. But there is not a single picture of a fire in the American Southeast, despite researchers warning that the lower righthand quadrant of the country will face a “perfect storm” of fire conditions over the next 50 years.

    In what is perhaps a grim premonition of what is to come, several major fires are burning across the Southeast now — including the nearly 600-acre Melrose Fire in Polk County, North Carolina, a little over 80 miles to the west of Charlotte, and the more than 2,000-acre Carolina Forest fire in Horry County, South Carolina. The region is also battling hundreds of smaller brush fires, the smoke from which David Wear — the land use, forestry, and agriculture program director at Resources for the Future — could see out his Raleigh-area window.

    Keep reading...Show less
    Green