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Inside Climeworks’ big experiment to wrest carbon from the air

In the spring of 2021, the world’s leading authority on energy published a “roadmap” for preventing the most catastrophic climate change scenarios. One of its conclusions was particularly daunting. Getting energy-related emissions down to net zero by 2050, the International Energy Agency said, would require “huge leaps in innovation.”
Existing technologies would be mostly sufficient to carry us down the carbon curve over the next decade. But after that, nearly half of the remaining work would have to come from solutions that, for all intents and purposes, did not exist yet. Some would only require retooling existing industries, like developing electric long-haul trucks and carbon-free steel. But others would have to be built from almost nothing and brought to market in record time.
What will it take to rapidly develop new solutions, especially those that involve costly physical infrastructure and which have essentially no commercial value today?
That’s the challenge facing Climeworks, the Swiss company developing machines to wrest carbon dioxide molecules directly from the air. In September 2021, a few months after the IEA’s landmark report came out, Climeworks switched on its first commercial-scale “direct air capture” facility, a feat of engineering it dubbed “Orca,” in Iceland.
The technology behind Orca is one of the top candidates to clean up the carbon already blanketing the Earth. It could also be used to balance out any stubborn, residual sources of greenhouse gases in the future, such as from agriculture or air travel, providing the “net” in net-zero. If we manage to scale up technologies like Orca to the point where we remove more carbon than we release, we could even begin cooling the planet.
As the largest carbon removal plant operating in the world, Orca is either trivial or one of the most important climate projects built in the last decade, depending on how you look at it. It was designed to capture approximately 4,000 metric tons of carbon from the air per year, which, as one climate scientist, David Ho, put it, is the equivalent of rolling back the clock on just 3 seconds of global emissions. But the learnings gleaned from Orca could surpass any quantitative assessment of its impact. How well do these “direct air capture” machines work in the real world? How much does it really cost to run them? And can they get better?
The company — and its funders — are betting they can. Climeworks has made major deals with banks, insurers, and other companies trying to go green to eventually remove carbon from the atmosphere on their behalf. Last year, the company raised $650 million in equity that will “unlock the next phase of its growth,” scaling the technology “up to multi-million-ton capacity … as carbon removal becomes a trillion-dollar market.” And just last month, the U.S. Department of Energy selected Climeworks, along with another carbon removal company, Heirloom, to receive up to $600 million to build a direct air capture “hub” in Louisiana, with the goal of removing one million tons of carbon annually.
Two years after powering up Orca, Climeworks has yet to reveal how effective the technology has proven to be. But in extensive interviews, top executives painted a picture of innovation in progress.
Chief marketing officer Julie Gosalvez told me that Orca is small and climatically insignificant on purpose. The goal is not to make a dent in climate change — yet — but to maximize learning at minimal cost. “You want to learn when you're small, right?” Gosalvez said. “It’s really de-risking the technology. It’s not like Tesla doing EVs when we have been building cars for 70 years and the margin of learning and risk is much smaller. It’s completely new.”
From the ground, Orca looks sort of like a warehouse or a server farm with a massive air conditioning system out back. The plant consists of eight shipping container-sized boxes arranged in a U-shape around a central building, each one equipped with an array of fans. When the plant is running, which is more or less all the time, the fans suck air into the containers where it makes contact with a porous filter known as a “sorbent” which attracts CO2 molecules.

When the filters become totally saturated with CO2, the vents on the containers snap shut, and the containers are heated to more than 212 degrees Fahrenheit. This releases the CO2, which is then delivered through a pipe to a secondary process called “liquefaction,” where it is compressed into a liquid. Finally, the liquid CO2 is piped into basalt rock formations underground, where it slowly mineralizes into stone. The process requires a little bit of electricity and a lot of heat, all of which comes from a carbon-free source — a geothermal power plant nearby.
A day at Orca begins with the morning huddle. The total number on the team is often in flux, but it typically has a staff of about 15 people, Climeworks’ head of operations Benjamin Keusch told me. Ten work in a virtual control room 1,600 miles away in Zurich, taking turns monitoring the plant on a laptop and managing its operations remotely. The remainder work on site, taking orders from the control room, repairing equipment, and helping to run tests.
During the huddle, the team discusses any maintenance that needs to be done. If there’s an issue, the control room will shut down part of the plant while the on-site workers investigate. So far, they’ve dealt with snow piling up around the plant that had to be shoveled, broken and corroded equipment that had to be replaced, and sediment build-up that had to be removed.

The air is more humid and sulfurous at the site in Iceland than in Switzerland, where Climeworks had built an earlier, smaller-scale model, so the team is also learning how to optimize the technology for different weather. Within all this troubleshooting, there’s additional trade-offs to explore and lessons to learn. If a part keeps breaking, does it make more sense to plan to replace it periodically, or to redesign it? How do supply chain constraints play into that calculus?
The company is also performing tests regularly, said Keusch. For example, the team has tested new component designs at Orca that it now plans to incorporate into Climeworks’ next project from the start. (Last year, the company began construction on “Mammoth,” a new plant that will be nine times larger than Orca, on a neighboring site.) At a summit that Climeworks hosted in June, co-founder Jan Wurzbacher said the company believes that over the next decade, it will be able to make its direct air capture system twice as small and cut its energy consumption in half.
“In innovation lingo, the jargon is we haven’t converged on a dominant design,” Gregory Nemet, a professor at the University of Wisconsin who studies technological development, told me. For example, in the wind industry, turbines with three blades, upwind design, and a horizontal axis, are now standard. “There were lots of other experiments before that convergence happened in the late 1980s,” he said. “So that’s kind of where we are with direct air capture. There’s lots of different ways that are being tried right now, even within a company like Climeworks."
Although Climeworks was willing to tell me about the goings-on at Orca over the last two years, the company declined to share how much carbon it has captured or how much energy, on average, the process has used.
Gosalvez told me that the plant’s performance has improved month after month, and that more detailed information was shared with investors. But she was hesitant to make the data public, concerned that it could be misinterpreted, because tests and maintenance at Orca require the plant to shut down regularly.
“Expectations are not in line with the stage of the technology development we are at. People expect this to be turnkey,” she said. “What does success look like? Is it the absolute numbers, or the learnings and ability to scale?”
Danny Cullenward, a climate economist and consultant who has studied the integrity of various carbon removal methods, did not find the company’s reluctance to share data especially concerning. “For these earliest demonstration facilities, you might expect people to hit roadblocks or to have to shut the plant down for a couple of weeks, or do all sorts of things that are going to make it hard to transparently report the efficiency of your process, the number of tons you’re getting at different times,” he told me.
But he acknowledged that there was an inherent tension to the stance, because ultimately, Climeworks’ business model — and the technology’s effectiveness as a climate solution — depend entirely on the ability to make precise, transparent, carbon accounting claims.
Nemet was also of two minds about it. Carbon removal needs to go from almost nothing today to something like a billion tons of carbon removed per year in just three decades, he said. That’s a pace on the upper end of what’s been observed historically with other technologies, like solar panels. So it’s important to understand whether Climeworks’ tech has any chance of meeting the moment. Especially since the company faces competition from a number of others developing direct air capture technologies, like Heirloom and Occidental Petroleum, that may be able to do it cheaper, or faster.
However, Nemet was also sympathetic to the position the company was in. “It’s relatively incremental how these technologies develop,” he said. “I have heard this criticism that this is not a real technology because we haven’t built it at scale, so we shouldn’t depend on it. Or that one of these plants not doing the removal that it said it would do shows that it doesn’t work and that we therefore shouldn’t plan on having it available. To me, that’s a pretty high bar to cross with a climate mitigation technology that could be really useful.”
More data on Orca is coming. Climeworks recently announced that it will work with the company Puro.Earth to certify every ton of CO2 that it removes from the atmosphere and stores underground, in order to sell carbon credits based on this service. The credits will be listed on a public registry.
But even if Orca eventually runs at full capacity, Climeworks will never be able to sell 4,000 carbon credits per year from the plant. Gosalvez clarified that 4,000 tons is the amount of carbon the plant is designed to suck up annually, but the more important number is the amount of “net” carbon removal it can produce. “That might be the first bit of education you need to get out there,” she said, “because it really invites everyone to look at what are the key drivers to be paid attention to.”
She walked me through a chart that illustrated the various ways in which some of Orca’s potential to remove carbon can be lost. First, there’s the question of availability — how often does the plant have to shut down due to maintenance or power shortages? Climeworks aims to limit those losses to 10%. Next, there’s the recovery stage, where the CO2 is separated from the sorbent, purified, and liquified. Gosalvez said it’s basically impossible to do this without losing some CO2. At best, the company hopes to limit that to 5%.
Finally, the company also takes into account “gray emissions,” or the carbon footprint associated with the business, like the materials, the construction, and the eventual decommissioning of the plant and restoration of the site to its former state. If one of Climeworks’ plants ever uses energy from fossil fuels (which the company has said it does not plan to do) it would incorporate any emissions from that energy. Climeworks aims to limit gray emissions to 15%.
In the end, Orca’s net annual carbon removal capacity — the amount Climeworks can sell to customers — is really closer to 3,000 tons. Gosalvez hopes other carbon removal companies adopt the same approach. “Ultimately what counts is your net impact on the planet and the atmosphere,” she said.
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Despite being a first-of-its-kind demonstration plant — and an active research site — Orca is also a commercial project. In fact, Gosalvez told me that Orca’s entire estimated capacity for carbon removal, over the 12 years that the plant is expected to run, sold out shortly after it began operating. The company is now selling carbon removal services from its yet-to-be-built Mammoth plant.
In January, Climeworks announced that Orca had officially fulfilled orders from Microsoft, Stripe, and Shopify. Those companies have collectively asked Climeworks to remove more than 16,000 tons of carbon, according to the deal-tracking site cdr.fyi, but it’s unclear what portion of that was delivered. The achievement was verified by a third party, but the total amount removed was not made public.
Climeworks has also not disclosed how much it has charged companies per ton of carbon, a metric that will eventually be an important indicator of whether the technology can scale to a climate-relevant level. But it has provided rough estimates of how much it expects each ton of carbon removal to cost as the technology scales — expectations which seem to have shifted after two years of operating Orca.
In 2021, Climeworks co-founder Jan Wurzbacher said the company aimed to get the cost down to $200 to $300 per ton removed by the end of the decade, with steeper declines in subsequent years. But at the summit in June, he presented a new cost curve chart showing that the price was currently more than $1,000, and that by the end of the decade, it would fall to somewhere between $400 to $700. The range was so large because the cost of labor, energy, and storing the CO2 varied widely by location, he said. The company aims to get the price down to $100 to $300 per ton by 2050, when the technology has significantly matured.
Critics of carbon removal technologies often point to the vast sums flowing into direct air capture tech like Orca, which are unlikely to make a meaningful difference in climate change for decades to come. During a time when worsening disasters make action feel increasingly urgent, many are skeptical of the value of investing limited funds and political energy into these future solutions. Carbon removal won’t make much of a difference if the world doesn’t deploy the tools already available to reduce emissions as rapidly as possible — and there’s certainly not enough money or effort going into that yet.
But we’ll never have the option to fully halt climate change, let alone begin reversing it, if we don’t develop solutions like Orca. In September, the International Energy Agency released an update to its seminal net-zero report. The new analysis said that in the last two years, the world had, in fact, made significant progress on innovation. Now, some 65% of emission reductions after 2030 could be accounted for with technologies that had reached market uptake. It even included a line about the launch of Orca, noting that Climeworks’ direct air capture technology had moved from the prototype to the demonstration stage.
But it cautioned that DAC needs “to be scaled up dramatically to play the role envisaged,” in the net zero scenario. Climeworks’ experience with Orca offers a glimpse of how much work is yet to be done.
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Facing down a sea change, the automaker has staked its next EV bet on a compact, sporty pickup.
“Full fathom five, your father lies,” the invisible spirit Ariel sings early in The Tempest, as a handsome and grieving prince listens, rapt. The song tells of a shipwrecked skeleton transforming into something else — its eyes have become pearls, and its bones pink coral — as it undergoes, yes, a “sea change.” It is the first time that phrase appears in the English language.
Ford is now facing its own kind of sea change. Over the past decade, the automaker has doubled down on its most profitable and exciting vehicles — pickups, SUVs, and the Mustang muscle car — and dropped from its line-up the cheap, boring cars that once made it famous. It embraced, then backed off, the transition to electric vehicles, in part because it failed to make money from them; and it began to reckon with the surge of cheaper, cleaner, and “far superior” EVs from Chinese producers that are transforming global auto markets around the world.
Locked into its aging but reliable line-up, yet unable to innovate at the low end, Ford might seem like the epitome of a company facing disruptive innovation. No wonder its stock has traded flat from where it was five years ago — even as the broader market has surged by more than 70%.
Its solution is an EV skunkworks, run by Tesla alumni, where it can develop a new “universal EV platform” to undergird future vehicles. Today, we got a peek at the first car to emerge from that secret shop: an all-electric compact pickup that will hit the roads by the end of next year. Its name? The Ford Fathom.
We know very little about the Fathom, as our correspondent Andrew Moseman wrote today. It will retail for just over $28,000, and even with mandatory delivery costs and other add-ons will stick to this side of $30,000. That makes it only a smidge more expensive than the gas-burning Ford Maverick, a sporty, compact, and popular pickup that starts around $27,000.
Ford promises that the Fathom will have as much seating capacity as Toyota’s RAV4, America’s best-selling car that isn’t a truck. (Ford’s own F-150, of course, holds the true No. 1 spot.) Those dimensions suggest the Fathom will sport a four-door crew cab, like the Maverick, making it more acceptable to families with kids — or young professionals who want to give their friends rides on the weekend. It will also have a frunk.
Beyond that, though, we don’t know much. We don’t know its range, for instance, and its price point shouldn’t inspire too much confidence on that front. Nor do we know, frankly, whether Ford can pull it off: When the automaker announced its first electric truck, the F-150 Lightning, in 2021, it claimed a price point of less than $40,000. Eighteen months of inflation later, it actually sold them for closer to $55,000 — and it still lost money on every EV that it made. Fixing the latter problem is part of why the skunkworks exists in the first place, and Ford now has an additional half-decade of experience making EVs. But consumers hoping for a miraculously priced electric pickup from the Blue Oval have been burned before.
If the Fathom disappoints, though, then consumers will soon have other options. The American car market is about to be deluged with sporty, compact pickup trucks — a welcome change from just a few years ago, when the segment was almost entirely dominated by mid-size and half-ton models. The Jeff Bezos-backed startup Slate will start delivering two-door, all-electric pickups starting at $25,000 at the end of this year. The automaker Stellantis, which owns the Dodge and Jeep brands, says it wants to bring another compact pickup — it’s almost more of a ute — called the Rampage to North America soon.
That’s welcome news for me — I love these little trucks — but I’m a little worried I’ll be outside my pickup-buying years by the time they actually make it to market. In the meantime, I’ll keep you posted on other updates about the Fathom. Will “sea nymphs hourly ring its knell”? No, but it will have Apple CarPlay and Android Auto.
The company confirmed its plans to market research company Cleanview.
The data center buildout has hit a new inflection point. It has long been true that artificial intelligence is fueling climate change by driving up power demand; more recently, tech companies have started directly financing new natural gas plants in their quest for AI glory. Now one is backing the biggest fossil fuel-fired power plant ever to exist in the United States — exclusively to power an AI data center complex.
That company is Amazon, according to the market research company Cleanview, which reported on Friday that the tech giant is building an AI data center campus in Texas powered by an up to 7.65-gigawatt off-grid natural gas plant.
That’s larger than any other power plant in the country — fossil or otherwise. The next biggest plant is the Grand Coulee hydroelectric plant in Washington State, at 7 gigawatts, followed by Arizona’s 4-gigawatt Palo Verde nuclear plant, and the West Count Energy Center, a 3.7-gigawatt natural gas plant in Florida.
The new power plant’s developer, Pacifico Energy, announced in January that it had secured permits from Texas regulators for the project, dubbed “GW Ranch.” The site is also permitted for up to 750 megawatts of solar and 1.8 gigawatts of battery energy storage.
It was not clear who the customer for all this energy would be until earlier this week, when Cleanview uncovered construction permits Amazon filed showing that the company owned the GW Ranch site. The company confirmed to Cleanview that it acquired the site and planned to buy power from Pacifico’s plant.
Not only will this natural gas plant be larger than the one in Florida, it will also use far less efficient technology. Pacifico’s permit says it plans to build 35 “simple cycle” generating units, which are typically installed in rarely-used peaker power plants and waste a lot more fuel potential than the modern “combined cycle” natural gas plants that serve as baseload power for the grid today. These more efficient turbines are essentially on backorder for years, and power-hungry developers have increasingly turned to the simpler versions as a quick fix as they race to bring facilities online.
According to its permit, the GW Ranch plant is allowed to emit as much as 33 million tons of CO2 per year. That’s twice as much as the most-polluting power plant in the country, the James H. Miller Jr. coal plant in Alabama, emitted in 2023, the most recent year for which data is available.
In a statement to Cleanview, an Amazon spokesperson said the company “believes in paying the full costs of powering our operations,” and that this Texas project “does just that: it’s powered by new on-site generation that won’t raise electricity costs for Texas families and designed to transition to grid-connected service as interconnection timelines allow.”
Some researchers disagree on that point, however. In an opinion piece for Utility Dive, Energy Innovation director Jeffrey Rissman and senior fellow Eric Gimon argue that the proliferation of off-grid natural gas generation for data centers will increase costs for regular people more than if the data centers connected to the grid, because they will be competing with utility companies for gas supply. “Data centers can buy gas in bulk and sign long-term contracts (as we’ve seen in Texas, Pennsylvania and New Mexico), giving them access to cheap gas, even if this unfairly drives up prices for everyone else,” they write.
Jane Flegal, a senior fellow at the Searchlight Institute, has also argued that building off-grid natural gas plants to serve data centers locks in emissions for decades because the plants don’t face competitive pressure from other resources. When a new natural gas plant is hooked up to the grid, by contrast, there’s a far greater chance that cheaper, cleaner resources will displace its generation over time.
The Rhodium Group recently developed a scoring system to help investors differentiate between projects that are likely to accelerate the energy transition, those that will have little effect one way or the other, and those that will actively slow it down. They used it to assess options for powering data centers, and found that off grid natural gas plants scored the worst, falling at the bottom of the latter category.
Regardless, Amazon still, somehow, asserts that it is committed to achieve net zero emissions by 2040.
The smoke pouring into Seattle from Spokane is particularly bad, but there’s also no such thing as good smoke.
I wrote this story from inside a cloud of smoke. Owing to some funky meteorology in the Seattle area this week — a pressure ridge paired with a thermal trough — the region’s usual westerly winds reversed, causing smoke from the fires burning in the eastern half of the state to pour through the mountain passes and river valleys of the Cascades and pool over the populous Puget Sound lowlands, where I live.
Though it’s cleared up some today, I’m still running my air purifier on full blast because I know what’s in the lingering smoke. Unlike the still blazing wildfires in Ontario that are burning through mostly uninhabited forests, the smoke in the Seattle area this week came to us partially from Spokane, where the Old Trails fire razed at least 700 buildings and homes last weekend. That means that beyond the usual organic matter associated with wildfire smoke, the pollution that has hung over Seattle has likely also contained particles and chemicals from burned plastics, batteries, cars, and household appliances.
But how can the average person be sure whether their wildfire smoke is the bad kind or the worse kind? (At least assuming that well-adjusted people do not obsessively watch the animations on AirNow.Gov, as I do.) I turned to Coty Jen, an associate professor of chemical engineering, and Albert Presto, a research professor of mechanical engineering, both of Carnegie Mellon University, to learn more about the chemistry of wildfire smoke.
“There is no safe smoke,” Jen said, setting me straight immediately. “It’s all bad. It will piss your body off.”
While it’s true that some smoke is more toxic than other smoke, what you might call the “all natural, organic” variety will still spike hospital emission rates and exacerbate pre-existing respiratory diseases, even if it is mostly burning trees.
Under ideal conditions, when cellulose or lignin — the main structural components of trees and plants as well as leaf litter and soil, the largest sources of carbon during a forest fire — heat up and combust, the chemical reaction creates carbon dioxide, water, heat, and light. But wildfires don’t burn cleanly, and the chemical reactions often stall midway through that process due to things like oxygen availability and temperature variation, producing intermediate products like carbon monoxide or partially broken-down bits of carbon, often called soot. The tiniest of these particles can be smaller than 2.5 micrometers across — 30 or more could fit across the width of a human hair — and are measured collectively as PM2.5, a catch-all term that refers to the size of the particle rather than what it is. What’s important, though, is that these particles are small enough to penetrate deep into our lungs and potentially enter our bloodstream, factors that add to the known mortality associated with PM2.5 exposure.
Different kinds of forests create different emissions — heavy duff, or leaf litter, which is common in pine forests, creates some of the densest smoke conditions. Wetter fuels also burn “dirtier,” creating more pollution. Different topographies also impact air quality in myriad ways; it’s no surprise that some of the worst pollution from the Spokane wildfires pooled in mountain valleys as a warm overhead layer of air trapped the particles near the ground.
Even “natural” wildfires can be extra toxic; burning eucalyptus, which grows in Southern California, is not something you want to inhale. Pine smoke can cause mutations in bacterial DNA, a common lab test for a substance’s potential to cause cancer. Wildfires that smolder are worse than those that burn fast; researchers have found that PM2.5 can be up to 70 times higher when fuels aren’t actively on fire. “You can even see this if you’ve ever built a fire yourself,” Presto explained. “There’s a period where everything is big and flaming, and then, if you’re burning a log, it eventually goes down to smoldering. The emissions are different.”
In the case of something like a house burning down in a wildfire, however, it’s not only cellulose and lignin combusting. “We’re good at engineering materials that are extremely robust, but when they burn, they release very exotic compounds,” Jen said. She pointed to the common plastic PVC, which is used for everything from exterior siding to plumbing and window frames. When it combusts, PVC releases chlorine, “which is very bad for you,” Jen told me. “It’s like how bleach is bad for you — it’s a pretty nasty chlorine compound. PVC isn’t releasing bleach, but it is releasing radical chlorine molecules that produce some crazy compounds.”
If you’re following a smoke event at home, the answer is “not really.” PM2.5 is measured in micrograms per cubic meter, which tells us how much small stuff is floating around, but not what that small stuff is. “It is pretty difficult to measure all the different compounds that wildfires, or broadly any pollution, will emit,” Jen said. “The easiest way to quantify it is to literally suck air onto a filter and measure how heavy it got.”
Measuring what exactly is in that mass requires instruments that cost in the ballpark of half a million dollars, which is not financially feasible at every air monitoring station, Jen went on. But while there are certainly academic applications for that kind of knowledge, a person trying to decide whether or not to go for their run in wildfire smoke doesn’t need that level of granularity.
“Some smoke is definitely more dangerous,” Jen said. “But as innocent bystanders, it’s not like we can pick and choose what smoke floats over to us. You just have to live with it, so the best mentality is to treat all smoke as bad.”
In a 2026 Science Advances study that attributed more than 24,000 deaths per year to wildfire smoke in the U.S., researchers found no safe threshold for PM2.5 exposure. Every 0.1 microgram per cubic meter increase in a county’s average annual PM2.5 from smoke was associated with nearly 5,600 excess deaths nationwide, even though most counties saw only trace amounts of smoke — about 0.4 micrograms per cubic meter a year. While it’s “orange sky” days, when the pollution spikes into triple-digit AQI numbers, that get the most media attention, even low exposure that you can’t smell or even see can be affecting your health.
PM2.5 is just one component of wildfire smoke — the other is gases, including benzene and formaldehyde. Many gases chemically transform as they move from where the fire is to where you inhale them. “The atmosphere is extremely oxidizing — it likes to add oxygen molecules onto compounds,” Jen said.
Some of those compounds react faster than others, “so it depends how downwind you are,” Jen went on. That’s why people closer to a wildfire — maybe a day or less downwind — get the distinctive campfire smell, mainly from the “young” vapors and volatile organic compounds. But for people on the East Coast who were subject to the Ontario smoke several weeks ago, the smoke had to travel several days to reach places like Pittsburgh and New York, and by then the sharper-smelling compounds had transformed into new pollutants like ozone.
The AQI only measures a few specific gases that are considered “criteria pollutants” under the Clean Air Act, which means, as Presto told me, “during these fires, you could emit a whole bunch of different other gases that don’t have an AQI number.”
Instead, you can look at the PM2.5 number to get the gist of how prevalent wildfire gases are. “If your PM 2.5 is high, it’s impossible for the bad gasses to be low,” Jen said. “The way we think about it is, there’s a bunch of junk on the particle, and if the same junk’s not also in the gas, it will evaporate off the particle into the gas. They always exist together.”
You might notice by now that I’ve written little about the actual AQI number, that score that appears on your weather app and runs from zero to 500 (or, confusingly, even higher). That’s because while the AQI is a great communication tool, it doesn’t offer us much in the way of the science of wildfire smoke.
The AQI measures five different pollutants — PM2.5, ozone, carbon monoxide, sulfur dioxide, and nitrogen dioxide — with the EPA setting specific concentration thresholds for each one, as my colleague Emily Pontecorvo has explained. “If local concentrations of any one of them tick up above those protective standards, the AQI will jump from green to a more alarming color,” she wrote. “The higher the level of pollution is, the higher the AQI and the darker the color will be.”
If you want to impress your friends, though, you ought to zero in specifically on the PM2.5 concentration — again, because the prevalence of the tiniest particulates is a good indicator of all the other gunk you can assume is in the air, too. (You can find the specific PM2.5 concentration usually by clicking for more information about the AQI on your weather app or checking IQ Air’s widget.) For example, at the time of this writing, my local PM2.5 concentration is 50 micrograms per cubic meter, more than triple the World Health Organization’s 15 micrograms per cubic meter threshold for 24-hour exposure. (The EPA’s 24-hour threshold is much more lenient, at 35 micrograms per cubic meter.)
When I asked Jen how she stays sane knowing all she knows about smoke exposure, she laughed. “I have just generally become more terrified of all campfires and all barbecues, but people already think I’m weird, so I might as well add to it,” she told me.
In all seriousness, though, she told me the answer is air filters, and her confidence in their ability to work. When wildfire smoke rolled through Pittsburgh, she had two running that she moved from room-to-room with her family, as well as a whole-house air filter. “We were getting PM2.5 concentrations in our house of about 80 micrograms per cubic meter when it was 150 outside,” she said. “But with the air filter on, we could drop that down to less than eight.”
Jen pointed out, though, that many people do not run their air filters properly. Filters are rated at their highest blower level, “so for them to be effective, you need to crank them to their highest setting to get all the air through,” she said. Most people keep their filters on auto or low because they’re so loud — myself included, until I learned otherwise.
Additionally, while an air filter is a rather large appliance, it really ought to be placed in the center of your room to be the most efficient, rather than up against a wall. (Again, my bad.) “When these wildfire events happen, the most effective place for the air filter is where you are, and you have to run it loud, which kind of sucks,” Jen said. “But it is better than breathing in gross air.”