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Pennsylvania is out, Virginia wants in, and New Jersey is treating it like a piggybank.

The Regional Greenhouse Gas Initiative has been quietly accelerating the energy transition in the Mid-Atlantic and Northeast since 2005. Lately, however, the noise around the carbon market has gotten louder as many of the compact’s member states have seen rising energy prices dominate their local politics.
What is RGGI, exactly? How does it work? And what does it have to do with the race for the 2028 Democratic presidential nomination?
Read on:
The Regional Greenhouse Gas Initiative is a cap and trade market with roots in a multistate compact formed in 2005 involving Connecticut, Delaware, Maine, New Hampshire, New Jersey, New York, and Vermont.
The goal was to reduce emissions, and the mechanism would be regular auctions for emissions “allowances,” which large carbon-emitting electricity generators would have to purchase at auction. Over time, the total number of allowances in circulation would shrink, making each one more expensive and encouraging companies to reduce their emissions. The cap started at 188 million short tons of carbon and has been dropping steadily ever since, with an eventual target of under 10 million by 2037.
By the time of the first auction in 2008, six states were fully participating — Delaware, New Hampshire, New Jersey, and New York were out; Maryland, Massachusetts, and Rhode Island were in — and together they raised almost $39 million. By the second auction later that year, 10 states — the six from the previous auction, plus New York, New Jersey, New Hampshire, and Delaware — were fully participating.
Membership has grown and shrunk over the years (for reasons we’ll cover below) but the current makeup is the same as it was at the end of 2008.
When carbon pricing schemes were first dreamt up by economists, the basic thinking was that by taxing something bad (carbon emissions) you could reduce taxes on something good (like wages or income). Real existing carbon pricing schemes, however, have tended to put their proceeds toward further decarbonization rather than reducing taxes or other costs.
In the case of the RGGI, the bulk of revenue goes to fund state climate programs. About two-thirds of investments from RGGI revenues in 2023 went to energy efficiency programs, which have received 56% of the system’s cumulative investments. By contrast, 15% of the 2023 investments (and 15% of the all-time investments) went to “direct bill assistance,” i.e. lowering utility bills.
Carbon dioxide emissions from the power sector have fallen by 40% to 50% in the RGGI territory since the program began — faster than in the U.S. as a whole.
That’s in part because the areas covered by RGGI have seen some of the sharpest transitions away from coal-fired power. New England, for instance, saw its last coal plant shut down late last year.
But it’s not always easy to figure out what was the effect of RGGI versus broader shifts in the energy industry. In the emissions-trading system’s early years, allowance prices were very low, and actual emissions fell well below the cap. That was largely due to factors affecting the country as a whole, including sluggish demand growth for electricity. The fracking boom also sent natural gas prices plunging, accelerating the switch from coal to gas and decelerating carbon dioxide emissions from the power sector (although this effect may have been more limited in the RGGI region, much of which has insufficient natural gas pipeline capacity).
That said, RGGI still might have helped tip the scales, Dallas Burtraw, a senior fellow at Resources for the Future, told me.
“It takes only a modest carbon price to really push out coal,” he said, pointing to the experience of RGGI and arguing that it could be replicated in other states. A 2016 paper by Man-Kuen Kim and Taehoo kim published in Energy Economics found “strong evidence that coal to gas switching has been actually accelerated by RGGI implementation.”
That trick doesn’t work as well now as it used to, though. “For the first 10 years or so, the primary margin for achieving emission reductions was substitution from coal to gas,” Burtraw told me. Then renewables prices began to drop “precipitously” in the early 2010s, opening up the opportunity for more thoroughgoing decarbonization beyond just getting rid of coal. “Going forward, I think program advocates would say that now you’re seeing the move from gas to renewables with storage,” he said.
When RGGI went through its regular program review in 2012 (these happen every few years; the third was completed last year), the target had to be wrenched downward to account for the actual path of emissions, which had dropped far more quickly than the cap.
“Soon after the start of RGGI, it became apparent that the number of allowances in the emissions budget was higher than actual emissions. Allowance prices consequently dropped, making it particularly inexpensive to purchase allowances and bank them for use in later periods,” a case study published by the Environmental Defense Fund found. In other words, because there was such a gap between the proscribed cap and actual emissions, generators had been able to squirrel away enough allowances to make future caps ineffective.
The arguments against the RGGI have been relatively constant and will be familiar to anyone following debates over energy and climate policy: RGGI raises prices for consumers, its opponents say. It pushes out reliable and cheaper energy sources, and thereby threatens jobs in fossil fuel generation and infrastructure. Also the particulars of how a state joins or exits the group have often come up for debate.
Three states have proved troublesome, including one original member and two later joiners: New Jersey, Virginia, and Pennsylvania. All three states are sizable energy consumers, and Virginia and Pennsylvania have substantial fossil fuel infrastructure and production.
New Jersey quickly expressed its discontent. In 2011, New Jersey’s Republican Governor Chris Christie decided to take the state out of the market, saying that it was unnecessary and costly. Democrat Phil Murphy, Christie’s successor, brought it back in 2020 as part of a broader agenda to decarbonize New Jersey’s economy.
Pennsylvania attempted to join next, in 2019, but ran into legal hurdles almost immediately. Governor Tom Wolf, a Democrat, issued an executive order in 2019 to set up carbon trading in the state, and state regulators got to work drawing up rules to allow Pennsylvania to link up with RGGI, formally joining in 2022.
But the following year, a Pennsylvania court ruled that the state was not able to participate because the regulatory work ordered by Wolf had been approved by the legislature. The case worked its way up to the state’s highest court last spring, but got tossed in January after Governor Josh Shapiro, a Democrat, made a budget deal with the state legislature late last year removing Pennsylvania from RGGI once and for all — more on that below.
Virginia was the last new state to join in 2020, under Democratic Governor Ralph Northam, who said that by joining, Virginia was “sending a powerful signal that our commonwealth is committed to fighting climate change and securing a clean energy future.” A year later, however, Democrats lost the governorship to Republican Glenn Youngkin, who defeated former governor Terry McAuliffe in the 2021 election. Youngkin then removed Virginia from RGGI at the end of 2023.
Youngkin described the exit — technically a choice made by state regulators — as a “commonsense decision by the Air Board to repeal RGGI protects Virginians from the failed program that is not only a regressive tax on families and businesses across the Commonwealth, but also does nothing to reduce pollution.”
Pennsylvania fits uneasily into the Northeastern–blue hue of the RGGI’s core states. It’s larger than any state in the system besides New York, right down the center politically, and is a substantial producer and exporter of electricity, much of it coming from fossil fuels (and nuclear power). It also has lower electricity costs than its neighbors to the east.
Pennsylvania’s governor, Josh Shapiro, is widely expected to run for the Democratic presidential nomination in 2028, and has put reining in electricity costs at the center of his messaging of late. He sued PJM, the mid-Atlantic electricity market at the end of 2024, and won a settlement to cap costs in the system’s capacity auctions. He also helped negotiate a “statement of principles” with the White House in order to potentially get those caps extended. And earlier this month, he met with utility executives “to discuss steps they can take to lower utility costs and protect consumers,” Will Simons, a spokesperson for the governor, said.
Pennsylvania’s permanent and undisputed inclusion in the RGGI system would be a coup. Unlike its neighbor RGGI states, including Maryland, Delaware, New Jersey, and New York, Pennsylvania still has a meaningful coal industry, meaning that its emissions could potentially fall substantially with a modest carbon price. It would also provide some relief to the rest of the system by notching significant emissions reductions at lower cost, meaning that electricity prices would likely be minimally affected or even go down, according to research done in 2023 by Burtraw, Angela Pachon, and Maya Domeshek.
“Pennsylvania is the source of a lot of low-cost emission reductions precisely because it still retains that coal-to-gas margin,” Burtraw said. “It looks the way the Northeastern states looked 15 years ago.”
But alas, it won’t happen. As part of a budget deal with Republicans reached late last year, Pennsylvania exited RGGI. That Shapiro would be willing to sacrifice RGGI isn’t shocking considering his record — when he ran for governor in 2021, he often put more emphasis on investing in clean energy than restricting fossil fuels. As governor, he has pushed for regulatory reforms, and even a Pennsylvania-specific cap and trade program, but Senate Republicans made RGGI exit the price of any energy policy talks.
Virginia may be ready to return to the fold.
“For me, this is about cost savings,” newly installed governor Abigail Spanberger said in her inaugural address. “RGGI generated hundreds of millions of dollars for Virginia — dollars that went directly to flood mitigation, energy efficiency programs, and lowering bills for families who need help most.” Furthermore, “withdrawing from RGGI did not lower energy costs,” she said. “In fact, the opposite happened — it just took money out of Virginia’s pocket,” referring to lost gains from RGGI auctions. (Research by Burtraw, Maya Domeshek, and Karen Palmer found that RGGI participation was the “lowest-cost way” of achieving the state’s statutory emissions reductions goals and that the funded investments in efficiency will likely drive down household costs.)
Virginia’s newly elected Attorney General Jay Jones also reversed the position of his Republican predecessor, signing on to litigation against Youngkin’s withdrawal from the program, arguing that the governor lacked the legal authority to withdraw from the program in the first place —the inverse of Pennsylvania’s legal tangle over RGGI.
New Jersey, too, has a new governor, Democrat Mikie Sherrill. In a set of executive orders, signed before she had even finished her inaugural address, Sherrill directed New Jersey economic, environment, and utility regulatory officials to “confer about the use of Regional Greenhouse Gas Initiative … proceeds for ratepayer relief,” and “include an explanation of how they intend to address ratepayer relief in the 2026-2028 RGGI Strategic Funding Plan.”
Ratepayers are already due to receive RGGI funding under New Jersey’s current strategic funding plan, as are environmental protection and energy efficiency programs, renewable and transmission investments, and a grab-bag of other climate related projects. New Jersey utility regulators last fall made a $430 million distribution to ratepayers in the form of two $50 bill credits, with additional $25 a month credits for low-income ratepayers.
The evolution of RGGI — and its use by New Jersey to reduce electricity bills in particular — shows how carbon mitigation programs have had to adapt to political realities.
“In the political context of the moment, I think it’s totally fair,” Burtraw told me of Sherrill’s plan. “It’s the worst good idea of what you can do with the carbon proceeds. Everybody in the room can come up with better ideas: Oh, we should be doing this investment, or we should be doing energy efficiency, or we should subsidize renewables. Show me that those ideas are a higher value use for that money and I’m all in. But we could at least be doing this.”
What remains to be seen is whether other states pick up the torch from Sherrill and start using RGGI as a way to more directly combat electricity price hikes. Her actions “could create ripple effects for other states that may face similar concerns,” Olivia Windorf, U.S. policy fellow at the Center for Climate and Energy Solutions, told me.
While RGGI tends to be in the news in the individual states only when there’s some controversy about entering or exiting the program, “the focus on electricity prices and affordability is putting a new spotlight on it,” Windorf said.
More aggressive or creative uses of the proceeds would put RGGI closer to the center of debates around affordability. “I think it will help address affordability concerns in a way that's really tangible,” Windorf said. “So it’s not abstract how carbon markets and RGGI can help through this time of load growth and energy transition. It can be a tool rather than a burden.”
Editor’s note: This story has been updated to correct the candidates for the governorship of Virginia in 2021.
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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.”