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Carbon removal would seem to have a pretty clear definition. It’s the reverse of carbon emissions. It means taking carbon out of the atmosphere and putting it somewhere else — underground, into products, into the ocean — where it won’t warm the planet. But a new kind of carbon removal project shows how this formula can conceal consequential differences between approaches.
A few months ago, Puro.earth, a carbon removal registry, certified a small ethanol refinery in North Dakota to sell carbon removal credits — the first ethanol plant to earn this privilege. Red Trail Energy, which owns the facility, captures the CO2 released from the plant when corn is fermented into ethanol, and injects it into a porous section of rock more than 6,000 feet underground. Since Red Trail started doing this in June of 2022, it’s prevented some 300,000 metric tons of CO2 from entering the atmosphere, according to data published by the North Dakota Department of Mineral Resources.
There are two ways to look at what’s happening here.
If you just follow the carbon, it started in the atmosphere and ended up underground. In between, the corn sucked up carbon through photosynthesis; when it was processed into ethanol, about a third of that carbon went into the fuel, a third was left behind as dried grain, and the remainder was captured as it wafted out of the fermentation tank and stashed underground. “That is, in a broad sense, how that looks like carbon removal,” Daniel Sanchez, an assistant professor at the University of California, Berkeley who studies biomass carbon removal, told me.
But if you zoom out, the picture changes. For the carbon to get from the atmosphere to the ground, a few other things had to happen. The corn had to be grown, harvested, and transported in trucks to the plant. It had to be put through a mill, cooked, and then liquified using heat from a natural gas boiler. And this was all in service, first and foremost, of producing ethanol to be burned, ultimately, in a car engine. If you account for the CO2 emitted during these other steps, the process as a whole is putting more into the atmosphere than it’s taking out.
So, is Red Trail Energy really doing carbon removal?
Puro.earth takes the first view — the registry’s rules essentially draw a box around the carbon capture and storage, or CCS, part of the process. Red Trail has to count the emissions from the energy it took to capture and liquify and inject the carbon, but not from anything else that happened before that. So far, Puro has issued just over 157,000 carbon removal credits for Red Trail to sell.
This is, essentially, industry consensus. Other carbon market registries including Gold Standard, Verra, and Isometric more or less take the same approach for any projects involving biomass, though they haven’t certified any ethanol projects yet. (Isometric’s current rules disqualify ethanol plants because they only allow projects that use waste biomass.)
But the nonprofit CarbonPlan, a watchdog for the carbon removal industry, argues that it’s a mistake to call this carbon removal. In a blog post published in December, program lead Freya Chay wrote that because the carbon storage is “contingent upon the continued production of ethanol,” it’s wrong to separate the two processes. The project reduces the facility’s overall emissions, Chay argued, but it’s not “carbon removal.”
This debate may sound semantic, and to some extent, it is. As long as an action results in less pollution warming the planet, does it matter whether we label it “carbon removal” or “emission reduction”?
The point of carbon credits is that they are paying for an intervention that wouldn’t have happened otherwise. “You have to look at, what part of the project is being built because they receive carbon removal credits?” Marianne Tikkanen, the co-founder and head of standard at Puro told me. “In this case, it was the capture part.” Previously, the emissions from the fermentation tank were considered to be zero, since the carbon started in the atmosphere and ended up back in the atmosphere. If you just look at the change that the sale of credits supported, those emissions are now negative.
But the logic of carbon credits may not be totally aligned with the point of carbon removal. Scientists generally see three roles for technologies that remove carbon from the atmosphere. The first is to reduce net emissions in the near term — Red Trail’s project checks that box. In the medium term, carbon removal can counteract any remaining emissions that we don’t know how to eliminate. That’s how we’ll “achieve net-zero” and stop the planet from warming.
But those who say these labels really matter are thinking of the third role. In the distant future, if we achieve net-zero emissions, but global average temperatures have reached dangerous heights, doing additional carbon removal — and lowering the total concentration of CO2 in the atmosphere — will be our only hope of cooling the planet. If this is the long term goal, there is a “clear conceptual problem” with calling a holistic process that emits more than it removes “carbon removal,” Chay told me.
“I think the point of definitions is to help us navigate the world,” she said. “It will be kind of a miracle if we get there, but that is the lighthouse.”
Red Trail may have been the first ethanol company to get certified to sell carbon removal credits, but others are looking to follow in its footsteps. Chay’s blog post, written in December, was responding to news of another project: Summit Carbon Solutions, a company trying to build a major pipeline through the midwest that will transport CO2 captured from ethanol refineries and deliver it to an underground well in North Dakota, announced a deal to pre-sell $30 million worth of carbon removal credits from the project; it plans to certify the credits through Gold Standard. In May, Summit announced it planned to sell more than 160 million tons of carbon removal credits over the next decade.
Decarbonization experts often refer to the emissions from ethanol plants as low-hanging fruit. Out of all the polluting industries that we could be capturing carbon from, ethanol is one of the easiest. The CO2 released when corn sugar is fermented is nearly 100% pure, whereas the CO2 that comes from fossil fuel combustion is filled with all kinds of chemicals that need to be scrubbed out first.
Even if it’s relatively easy, though, it’s not free, and the ethanol industry has historically ignored the opportunity. But in the past few years, federal tax credits and carbon markets have made the idea more attractive.
Red Trail’s CCS project has been a long time in the making. The company began looking into CCS in 2016, partnering with the Energy and Environmental Research Center, the North Dakota Industrial Commission Renewable Energy Council, and the U.S. Department of Energy on a five-year feasibility study. Jodi Johnson, Red Trail’s CEO, answered questions about the project by email. “Building a first-of-its-kind CCS project involved significant financial, technical, and regulatory risks,” she told me. “The technology, while promising, required substantial upfront investment and a commitment to navigating uncharted regulatory frameworks.”
The primary motivation for the project was the company’s “commitment to environmental stewardship and sustainability,” Johnson said, but low-carbon fuel markets in California and Oregon were also a “strategic incentive.” Ethanol companies that sell into those states earn carbon credits based on how much cleaner their fuel is than gasoline. They can sell those credits to dirtier-fuel makers who need to comply with state laws. The carbon capture project would enable Red Trail to earn more credits — a revenue stream that at first, looked good enough to justify the cost. A 2017 economic assessment of the project found that it “may be economically viable,” depending on the specific requirements in the two states.
But today, two years after Red Trail began capturing carbon, the company’s application to participate in California’s low-carbon fuel market is still pending. Though the company does sell some ethanol into the Oregon market, it decided to try and sell carbon removal credits through Puro to support “broader decarbonization and sequestration efforts while awaiting regulatory approvals,” Johnson said. Red Trail had already built its carbon capture system prior to working with Puro, but it may not have operated the equipment unless it had an incentive to do so.
Puro didn’t just take Red Trail’s word for it. The project underwent a “financial additionality test” including an evaluation of other incentives for Red Trail to sequester carbon. For example, the company can earn up to $50 in tax credits for each ton of CO2 it puts underground. (The Inflation Reduction Act increased this subsidy to $85 per ton, but Red Trail is not eligible for the higher amount because it started building the project before the law went into effect.) In theory, this tax credit alone could be enough to finance the project. A recent report from the Energy Futures Initiative concluded that a first-of-a-kind CCS project at an ethanol plant should cost between $36 and $41 per ton of CO2 captured and stored.
Johnson told me Red Trail does not pay income tax at the corporate level, however — it is taxed as a partnership. That means individual investors can take advantage of the credit, but it’s not a big enough benefit to secure project finance. The project “requires significant capital expenditure, operating expense, regulatory, and long-term monitoring for compliance,” she said. “Access to the carbon market was the needed incentive to secure the investment and the continuous project operation.”
Ultimately, after an independent audit of Red Trail’s claims, Puro concluded that the company did, in fact, need to sell carbon removal credits to justify operating the CCS project. (Red Trail is currently also earning carbon credits for fuel sold in Oregon, but Puro is accounting for these and deducting credits from its registry accordingly.)
All this helps make the case that it’s reasonable to support projects like Red Trail’s through the sale of carbon credits. But it doesn’t explain why we should call it carbon removal.
When I put the question to Tikkanen, she said that the project interrupts the “short cycle” of carbon: The CO2 is captured during photosynthesis, it’s transferred into food or fuel, and then it’s released back into the air in a continuous loop — all in a matter of months. Red Trail is turning that loop into a one-way street from the atmosphere to the ground, taking more and more carbon out of the air over time. That’s different from capturing carbon at a fossil fuel plant, where the carbon in question had previously been trapped underground for millennia.
Robert Hoglund, a carbon removal advisor who co-founded the database CDR.fyi, had a similar explanation. He told me that it didn’t make sense to categorize this project as “reducing emissions” from the plant because the fossil fuel-burning trucks that deliver the corn and the natural gas boilers cooking it are still releasing the same amount of carbon into the atmosphere. “If we say only processes that, if they're scaled up, lead to lower emissions in the atmosphere are carbon removal, that's looking at it from a system perspective,” he said. “I can understand where they come from, but I think it does add some confusion.”
Red Trail Energy and Summit Carbon Solutions defended the label, noting that this is the way carbon market registries have decided to treat biomass-based carbon sequestration projects. “The fact that emissions remain from the lifecycle of the corn itself is not the focus of the removal activity,” Johnson told me. “The biogenic CO2 is clearly removed from the atmosphere permanently.”
Sanchez, the Berkeley professor, argued that Puro’s rules are adequate because there’s a path for ethanol plants to eventually achieve net-negative emissions. They will have to capture emissions from the boiler, in addition to the fermentation process, and make a few other tweaks, like using renewable natural gas, according to a recent peer-reviewed study Sanchez authored. “That's not what's happening here,” he told me, “but I view that as indicative that this is part of the basket of technologies that we use to reach net-zero and to suck CO2 out of the air.”
(Red Trail is working on reducing its emissions even more, Johnson told me. The company is finishing engineering on a new combined heat and power system that will improve efficiency at the plant.)
In addition to teaching at Berkeley, Sanchez is a principal scientist for the firm Carbon Direct, which helps corporate buyers find “high quality” carbon removal credits. He added that he felt the project was “worthy" of the dollars companies are designating for carbon removal because of the risk it involved, and the fact that it would blaze a trail for others to follow. Ethanol CCS projects will help build up carbon storage infrastructure and expertise, enabling other carbon removal projects in the future.
Though there is seeming consensus among carbon market participants that this is carbon removal, scientists outside the industry are more skeptical. Katherine Maher, an Earth systems scientist who studies the carbon cycle at Stanford University, said she understood the argument for calling ethanol with CCS carbon removal, but she also couldn’t ignore the fact that capturing the carbon requires energy to grow the corn, transport it, and so on. “You really need to be conscious about, what are the other emissions in the project, and are those being accounted for in the calculation of the CO2 removed?”
Carbon180, a nonprofit that advocates for carbon removal policy, shares that perspective. “When it comes to ethanol with CCS, we want to see the actual net negativity,” Sifang Chen, the group’s managing science and innovation advisor, told me.
In the U.S. Department of Energy’s Road to Removals report, a 221-page document that highlights all of the opportunities for carbon removal in the United States, the agency specifically chose not to analyze ethanol with CCS “due largely to its inability to achieve a negative [carbon intensity] without substantial retrofitting of existing corn-ethanol facilities.”
It’s possible to say that both views are correct. Each follows a clear logic — one more rooted in creating practical rules for a market in order to drive innovation, the other in the uncompromising math of atmospheric science.
At times throughout writing this, I wondered if I was making something out of nothing. But the debate has significance beyond ethanol. Sanchez pointed out to me that you could ask the same question about any so-called carbon removal process that’s tied to an existing industry. Take enhanced rock weathering, for example, which involves crushing up special kinds of rocks that are especially good at absorbing carbon from the air. A lot of the companies trying to do this get their rocks from mining waste, but they don’t include all the emissions from mining in their carbon removal calculation.
Similarly, Summit Carbon Solutions noted that CarbonPlan supports claims of carbon removal by Charm Industrial, a company that takes the biomass left behind in corn fields, turns it into oil, and sequesters the oil underground. In that case, the company is not counting emissions from corn production or the downstream uses of corn.
Chay admitted that she didn’t have a great answer for why she drew the boundaries differently for one versus the other. “We don’t claim to have all the answers, and this back-and-forth illustrates just how much ambiguity there is and why it’s important to work through these issues,” she told me in an email. But she suggested that one point of comparison is to look at how dependent the carbon removal activity is on “the ongoing operation of a net emitting industry, and how one thinks about the role of that emitting industry in a net-zero world.” There is no apparent version of the future where we no longer have mining as an industry, or no longer grow corn for food. But there is a path to eliminating the use of ethanol by electrifying transportation.
It’s worth mentioning that this niche debate about carbon removal is taking place within a much larger and longer controversy about whether ethanol belongs in a low-carbon future at all.
Red Trail told me the company sees the adoption of electric vehicles as an opportunity to diversify into making fuels for aviation and heavy-duty transportation, which are more difficult to electrify. But some environmental groups, like the World Resources Institute, argue that a more sustainable approach would be to develop synthetic fuels from captured carbon and hydrogen. I should note that experts from both sides of this debate told me that carbon credit sales should not justify keeping an ethanol plant open or building a new one if the economics of the fuel don’t work on their own.
In Chay’s blog post, she presented real stakes for this rhetorical debate. If we call net-emitting processes carbon removal, we could develop an inflated sense of how much progress we’ve made toward our overall capacity to remove carbon from the atmosphere, which in turn could warp perceptions of how quickly we need to reduce emissions.
Peter Minor, the former director of science and innovation at Carbon180 who is starting a company focused on measurement and verification, raised the same concern. “When the definition of what it means to remove a ton of CO2 from the air is subjective, what happens is you get a bunch of projects that might have quite different climate impacts,” he told me. “And you may or may not realize it until after the fact.”
There’s also a risk of diverting funding that could go toward scaling up more challenging, more expensive, but truly net-negative solutions such as direct air capture. This risk is compounded by the growing pressure on carbon market players like Puro and Carbon Direct to identify new, more affordable carbon removal projects. Over the past several years, influential groups like the Science Based Targets initiative and corporate sustainability thought leaders like Stripe and Microsoft have decided that old-school carbon credits — the cheaper so-called “offsets” that represent emissions reductions — are not good enough. Now companies are expected to buy carbon removal credits to fulfill their climate promises to customers, lest they be accused of greenwashing.
As a result, the industry has backed itself into a corner, Minor told me. “We have come out as a society and said, the only thing that is worth it, the only thing that is allowed to be used is carbon removal,” he said. “So if that's the only thing with economics behind it, then yeah, like, magic! Everything is now all of a sudden carbon removal! Who would have predicted that this could have happened?”
The success of carbon removal depends, ultimately, on integrity — the industry’s favorite word these days. From the companies trying to remove carbon, to the carbon credit registries validating those efforts, to the nonprofits, brokers, and buyers that want to see the market scale, everyone is talking about developing transparent and trustworthy processes for measuring how much carbon is removed from the atmosphere by a given intervention. But how good is good measurement if experts don’t agree on what should be measured?
“There hasn't been a way to standardize the climate impacts that are being promised,” said Minor. “And so I think unless we solve that problem, I just don't see how we're going to build the trust we need, to create the economics that we need and justify an industry that can’t really exist outside of the millions or billions of tons scale.”
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Instead of rocket fuel, they’re burning biomass.
Arbor Energy might have the flashiest origin story in cleantech.
After the company’s CEO, Brad Hartwig, left SpaceX in 2018, he attempted to craft the ideal resume for a future astronaut, his dream career. He joined the California Air National Guard, worked as a test pilot at the now-defunct electric aviation startup Kitty Hawk, and participated in volunteer search and rescue missions in the Bay Area, which gave him a front row seat to the devastating effects of wildfires in Northern California.
That experience changed everything. “I decided I actually really like planet Earth,” Hartwig told me, “and I wanted to focus my career instead on preserving it, rather than trying to leave it.” So he rallied a bunch of his former rocket engineer colleagues to repurpose technology they pioneered at SpaceX to build a biomass-fueled, carbon negative power source that’s supposedly about ten times smaller, twice as efficient, and eventually, one-third the cost of the industry standard for this type of plant.
Take that, all you founders humble-bragging about starting in a dingy garage.
“It’s not new science, per se,” Hartwig told me. The goal of this type of tech, called bioenergy with carbon capture and storage, is to combine biomass-based energy generation with carbon dioxide removal to achieve net negative emissions. Sounds like a dream, but actually producing power or heat from this process has so far proven too expensive to really make sense. There are only a few so-called BECCS facilities operating in the U.S. today, and they’re all just ethanol fuel refineries with carbon capture and storage technology tacked on.
But the advances in 3D printing and computer modeling that allowed the SpaceX team to build an increasingly simple and cheap rocket engine have allowed Arbor to move quickly into this new market, Hartwig explained. “A lot of the technology that we had really pioneered over the last decade — in reactor design, combustion devices, turbo machinery, all for rocket propulsion — all that technology has really quite immediate application in this space of biomass conversion and power generation.”
Arbor’s method is poised to be a whole lot sleeker and cheaper than the BECCS plants of today, enabling both more carbon sequestration and actual electricity production, all by utilizing what Hartwig fondly refers to as a “vegetarian rocket engine.” Because there’s no air in space, astronauts have to bring pure oxygen onboard, which the rocket engines use to burn fuel and propel themselves into the stratosphere and beyond. Arbor simply subs out the rocket fuel for biomass. When that biomass is combusted with pure oxygen, the resulting exhaust consists of just CO2 and water. As the exhaust cools, the water condenses out, and what’s left is a stream of pure carbon dioxide that’s ready to be injected deep underground for permanent storage. All of the energy required to operate Arbor’s system is generated by the biomass combustion itself.
“Arbor is the first to bring forward a technology that can provide clean baseload energy in a very compact form,” Clea Kolster, a partner and Head of Science at Lowercarbon Capital told me. Lowercarbon is an investor in Arbor, alongside other climate tech-focused venture capital firms including Gigascale Capital and Voyager Ventures, but the company has not yet disclosed how much it’s raised.
Last month, Arbor signed a deal with Microsoft to deliver 25,000 tons of permanent carbon dioxide removal to the tech giant starting in 2027, when the startup’s first commercial project is expected to come online. As a part of the deal, Arbor will also generate 5 megawatts of clean electricity per year, enough to power about 4,000 U.S. homes. And just a few days ago, the Department of Energy announced that Arbor is one of 11 projects to receive a combined total of $58.5 million to help develop the domestic carbon removal industry.
Arbor’s current plan is to source biomass from forestry waste, much of which is generated by forest thinning operations intended to prevent destructive wildfires. Hartwig told me that for every ton of organic waste, Arbor can produce about one megawatt hour of electricity, which is in line with current efficiency standards, plus about 1.8 tons of carbon removal. “We look at being as efficient, if not a little more efficient than a traditional bioenergy power plant that does not have carbon capture on it,” he explained.
The company’s carbon removal price targets are also extremely competitive — in the $50 to $100 per ton range, Hartwig said. Compare that to something like direct air capture, which today exceeds $600 per ton, or enhanced rock weathering, which is usually upwards of $300 per ton. “The power and carbon removal they can offer comes at prices that meet nearly unlimited demand,”Mike Schroepfer, the founder of Gigascale Capital and former CTO of Meta, told me via email. Arbor benefits from the fact that the electricity it produces and sells can help offset the cost of the carbon removal, and vice versa. So if the company succeeds in hitting its cost and efficiency targets, Hartwig said, this “quickly becomes a case for, why wouldn’t you just deploy these everywhere?”
Initial customers will likely be (no surprise here) the Microsofts, Googles and Metas of the world — hyperscalers with growing data center needs and ambitious emissions targets. “What Arbor unlocks is basically the ability for hyperscalers to stop needing to sacrifice their net zero goals for AI,” Kolster told me. And instead of languishing in the interminable grid interconnection queue, Hartwig said that providing power directly to customers could ensure rapid, early deployment. “We see it as being quicker to power behind-the-meter applications, because you don’t have to go through the process of connecting to the grid,” he told me. Long-term though, he said grid connection will be vital, since Arbor can provide baseload power whereas intermittent renewables cannot.
All of this could serve as a much cheaper alternative, to say, re-opening shuttered nuclear facilities, as Microsoft also recently committed to doing at Three Mile Island. “It’s great, we should be doing that,” Kolster said of this nuclear deal, “but there’s actually a limited pool of options to do that, and unfortunately, there is still community pushback.”
Currently, Arbor is working to build out its pilot plant in San Bernardino, California, which Hartwig told me will turn on this December. And by 2030, the company plans to have its first commercial plant operating at scale, generating 100 megawatts of electricity while removing nearly 2 megatons of CO2 every year. “To put it in perspective: In 2023, the U.S. added roughly 9 gigawatts of gas power to the grid, which generates 18 to 23 megatons of CO2 a year,” Schroepfer wrote to me. So having just one Arbor facility removing 2 megatons would make a real dent. The first plant will be located in Louisiana, where Arbor will also be working with an as-yet-unnamed partner to do the carbon storage.
The company’s carbon credits will be verified with the credit certification platform Isometric, which is also backed by Lowercarbon and thought to have the most stringent standards in the industry. Hartwig told me that Arbor worked hand-in-hand with Isometric to develop the protocol for “biogenic carbon capture and storage,” as the company is the first Isometric-approved supplier to use this standard.
But Hartwig also said that government support hasn’t yet caught up to the tech’s potential. While the Inflation Reduction Act provides direct air capture companies with $180 per ton of carbon dioxide removed, technology such as Arbor’s only qualifies for $85 per ton. It’s not nothing — more than the zero dollars enhanced rock weathering companies such as Lithos or bio-oil sequestration companies such as Charm are getting. “But at the same time, we’re treated the same as if we’re sequestering CO2 emissions from a natural gas plant or a coal plant,” Hartwig told me, as opposed to getting paid for actual CO2 removal.
“I think we are definitely going to need government procurement or involvement to actually hit one, five, 10 gigatons per year of carbon removal,” Hartwig said. Globally, scientists estimate that we’ll need up to 10 gigatons of annual CO2 removal by 2050 in order to limit global warming to 1.5 degrees Celsius. “Even at $100 per ton, 10 gigatons of carbon removal is still a pretty hefty price tag,” Hartwig told me. A $1 trillion price tag, to be exact. “We definitely need more players than just Microsoft.”
New research out today shows a 10-fold increase in smoke mortality related to climate change from the 1960s to the 2010.
If you are one of the more than 2 billion people on Earth who have inhaled wildfire smoke, then you know firsthand that it is nasty stuff. It makes your eyes sting and your throat sore and raw; breathe in smoke for long enough, and you might get a headache or start to wheeze. Maybe you’ll have an asthma attack and end up in the emergency room. Or maybe, in the days or weeks afterward, you’ll suffer from a stroke or heart attack that you wouldn’t have had otherwise.
Researchers are increasingly convinced that the tiny, inhalable particulate matter in wildfire smoke, known as PM2.5, contributes to thousands of excess deaths annually in the United States alone. But is it fair to link those deaths directly to climate change?
A new study published Monday in Nature Climate Change suggests that for a growing number of cases, the answer should be yes. Chae Yeon Park, a climate risk modeling researcher at Japan’s National Institute for Environmental Studies, looked with her colleagues at three fire-vegetation models to understand how hazardous emissions changed from 1960 to 2019, compared to a hypothetical control model that excluded historical climate change data. They found that while fewer than 669 deaths in the 1960s could be attributed to climate change globally, that number ballooned to 12,566 in the 2010s — roughly a 20-fold increase. The proportion of all global PM2.5 deaths attributable to climate change jumped 10-fold over the same period, from 1.2% in the 1960s to 12.8% in the 2010s.
“It’s a timely and meaningful study that informs the public and the government about the dangers of wildfire smoke and how climate change is contributing to that,” Yiqun Ma, who researches the intersection of climate change, air pollution, and human health at the Yale School of Medicine, and who was not involved in the Nature study, told me.
The study found the highest climate change-attributable fire mortality values in South America, Australia, and Europe, where increases in heat and decreases in humidity were also the greatest. In the southern hemisphere of South America, for example, the authors wrote that fire mortalities attributable to climate change increased from a model average of 35% to 71% between the 1960s and 2010s, “coinciding with decreased relative humidity,” which dries out fire fuels. For the same reason, an increase in relative humidity lowered fire mortality in other regions, such as South Asia. North America exhibited a less dramatic leap in climate-related smoke mortalities, with climate change’s contribution around 3.6% in the 1960s, “with a notable rise in the 2010s” to 18.8%, Park told me in an email.
While that’s alarming all on its own, Ma told me there was a possibility that Park’s findings might actually be too conservative. “They assume PM2.5 from wildfire sources and from other sources” — like from cars or power plants — “have the same toxicity,” she explained. “But in fact, in recent studies, people have found PM2.5 from fire sources can be more toxic than those from an urban background.” Another reason Ma suspected the study’s numbers might be an underestimate was because the researchers focused on only six diseases that have known links to PM2.5 exposure: chronic obstructive pulmonary disease, lung cancer, coronary heart disease, type 2 diabetes, stroke, and lower respiratory infection. “According to our previous findings [at the Yale School of Medicine], other diseases can also be influenced by wildfire smoke, such as mental disorders, depression, and anxiety, and they did not consider that part,” she told me.
Minghao Qiu, an assistant professor at Stony Brook University and one of the country’s leading researchers on wildfire smoke exposure and climate change, generally agreed with Park’s findings, but cautioned that there is “a lot of uncertainty in the underlying numbers” in part because, intrinsically, wildfire smoke exposure is such a complicated thing to try to put firm numbers to. “It’s so difficult to model how climate influences wildfire because wildfire is such an idiosyncratic process and it’s so random, ” he told me, adding, “In general, models are not great in terms of capturing wildfire.”
Despite their few reservations, both Qiu and Ma emphasized the importance of studies like Park’s. “There are no really good solutions” to reduce wildfire PM2.5 exposure. You can’t just “put a filter on a stack” as you (sort of) can with power plant emissions, Qiu pointed out.
Even prescribed fires, often touted as an important wildfire mitigation technique, still produce smoke. Park’s team acknowledged that a whole suite of options would be needed to minimize future wildfire deaths, ranging from fire-resilient forest and urban planning to PM2.5 treatment advances in hospitals. And, of course, there is addressing the root cause of the increased mortality to begin with: our warming climate.
“To respond to these long-term changes,” Park told me, “it is crucial to gradually modify our system.”
On the COP16 biodiversity summit, Big Oil’s big plan, and sea level rise
Current conditions: Record rainfall triggered flooding in Roswell, New Mexico, that killed at least two people • Storm Ashley unleashed 80 mph winds across parts of the U.K. • A wildfire that broke out near Oakland, California, on Friday is now 85% contained.
Forecasters hadn’t expected Hurricane Oscar to develop into a hurricane at all, let alone in just 12 hours. But it did. The Category 1 storm made landfall in Cuba on Sunday, hours after passing over the Bahamas, bringing intense rain and strong winds. Up to a foot of rainfall was expected. Oscar struck while Cuba was struggling to recover from a large blackout that has left millions without power for four days. A second system, Tropical Storm Nadine, made landfall in Belize on Saturday with 60 mph winds and then quickly weakened. Both Oscar and Nadine developed in the Atlantic on the same day.
Hurricane OscarAccuWeather
The COP16 biodiversity summit starts today in Cali, Colombia. Diplomats from 190 countries will try to come up with a plan to halt global biodiversity loss, aiming to protect 30% of land and sea areas and restore 30% of degraded ecosystems by 2030. Discussions will revolve around how to monitor nature degradation, hold countries accountable for their protection pledges, and pay for biodiversity efforts. There will also be a big push to get many more countries to publish national biodiversity strategies. “This COP is a test of how serious countries are about upholding their international commitments to stop the rapid loss of biodiversity,” said Crystal Davis, Global Director of Food, Land, and Water at the World Resources Institute. “The world has no shot at doing so without richer countries providing more financial support to developing countries — which contain most of the world’s biodiversity.”
A prominent group of oil and gas producers has developed a plan to roll back environmental rules put in place by President Biden, The Washington Post reported. The paper got its hands on confidential documents from the American Exploration and Production Council (AXPC), which represents some 30 producers. The documents include draft executive orders promoting fossil fuel production for a newly-elected President Trump to sign if he takes the White House in November, as well as a roadmap for dismantling many policies aimed at getting oil and gas producers to disclose and curb emissions. AXPC’s members, including ExxonMobil, ConocoPhillips, and Hess, account for about half of the oil and gas produced in the U.S., the Post reported.
A new report from the energy think tank Ember looks at how the uptake of electric vehicles and heat pumps in the U.K. is affecting oil and gas consumption. It found that last year the country had 1.5 million EVs on the road, and 430,000 residential heat pumps in homes, and the reduction in fossil fuel use due to the growth of these technologies was equivalent to 14 million barrels of oil, or about what the U.K. imports over a two-week span. This reduction effect will be even stronger as more and more EVs and heat pumps are powered by clean energy. The report also found that even though power demand is expected to rise, efficiency gains from electrification and decarbonization will make up for this, leading to an overall decline in energy use and fossil fuel consumption.
Ember
The world’s sea levels are projected to rise by more than 6 inches on average over the next 30 years if current trends continue, according to a new study published in the journal Nature. “Such rates would represent an evolving challenge for adaptation efforts,” the authors wrote. By examining satellite data, the researchers found that sea levels have risen by about .4 inches since 1993, and that they’re rising faster now than they were then. In 1993 the seas were rising by about .08 inches per year, and last year they were rising at .17 inches per year. These are averages, of course, and some areas are seeing much more extreme changes. For example, areas around Miami, Florida, have already seen sea levels rise by 6 inches over the last 31 years.
“As the climate crisis grows more urgent, restoring faith in government will be more important than ever.” –Paul Waldman writing for Heatmap about the profound implications of America becoming a low-trust society.