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      in Environment

      A new way to quantify climate change impacts: “Outdoor days”

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      For most people, reading about the difference between a global average temperature rise of 1.5 C versus 2 C doesn’t conjure up a clear image of how their daily lives will actually be affected. So, researchers at MIT have come up with a different way of measuring and describing what global climate change patterns, in specific regions around the world, will mean for people’s daily activities and their quality of life.

      The new measure, called “outdoor days,” describes the number of days per year that outdoor temperatures are neither too hot nor too cold for people to go about normal outdoor activities, whether work or leisure, in reasonable comfort. Describing the impact of rising temperatures in those terms reveals some significant global disparities, the researchers say.

      The findings are described in a research paper written by MIT professor of civil and environmental engineering Elfatih Eltahir and postdocs Yeon-Woo Choi and Muhammad Khalifa, and published in the Journal of Climate.

      Eltahir says he got the idea for this new system during his hourlong daily walks in the Boston area. “That’s how I interface with the temperature every day,” he says. He found that there have been more winter days recently when he could walk comfortably than in past years. Originally from Sudan, he says that when he returned there for visits, the opposite was the case: In winter, the weather tends to be relatively comfortable, but the number of these clement winter days has been declining. “There are fewer days that are really suitable for outdoor activity,” Eltahir says.

      Rather than predefine what constitutes an acceptable outdoor day, Eltahir and his co-authors created a website where users can set their own definition of the highest and lowest temperatures they consider comfortable for their outside activities, then click on a country within a world map, or a state within the U.S., and get a forecast of how the number of days meeting those criteria will change between now and the end of this century. The website is freely available for anyone to use.

      “This is actually a new feature that’s quite innovative,” he says. “We don’t tell people what an outdoor day should be; we let the user define an outdoor day. Hence, we invite them to participate in defining how future climate change will impact their quality of life, and hopefully, this will facilitate deeper understanding of how climate change will impact individuals directly.”

      After deciding that this was a way of looking at the issue of climate change that might be useful, Eltahir says, “we started looking at the data on this, and we made several discoveries that I think are pretty significant.”

      First of all, there will be winners and losers, and the losers tend to be concentrated in the global south. “In the North, in a place like Russia or Canada, you gain a significant number of outdoor days. And when you go south to places like Bangladesh or Sudan, it’s bad news. You get significantly fewer outdoor days. It is very striking.”

      To derive the data, the software developed by the team uses all of the available climate models, about 50 of them, and provides output showing all of those projections on a single graph to make clear the range of possibilities, as well as the average forecast.

      When we think of climate change, Eltahir says, we tend to look at maps that show that virtually everywhere, temperatures will rise. “But if you think in terms of outdoor days, you see that the world is not flat. The North is gaining; the South is losing.”

      While North-South disparity in exposure and vulnerability has been broadly recognized in the past, he says, this way of quantifying the effects on the hazard (change in weather patterns) helps to bring home how strong the uneven risks from climate change on quality of life will be. “When you look at places like Bangladesh, Colombia, Ivory Coast, Sudan, Indonesia — they are all losing outdoor days.”

      The same kind of disparity shows up in Europe, he says. The effects are already being felt, and are showing up in travel patterns: “There is a shift to people spending time in northern European states. They go to Sweden and places like that instead of the Mediterranean, which is showing a significant drop,” he says.

      Placing this kind of detailed and localized information at people’s fingertips, he says, “I think brings the issue of communication of climate change to a different level.” With this tool, instead of looking at global averages, “we are saying according to your own definition of what a pleasant day is, [this is] how climate change is going to impact you, your activities.”

      And, he adds, “hopefully that will help society make decisions about what to do with this global challenge.”

      The project received support from the MIT Climate Grand Challenges project “Jameel Observatory – Climate Resilience Early Warning System Network,” as well as from the Abdul Latif Jameel Water and Food Systems Lab. More

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      in Energy

      Lessons from Fukushima: Prepare for the unlikely

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      When a devastating earthquake and tsunami overwhelmed the protective systems at the Fukushima Dai’ichi nuclear power plant complex in Japan in March 2011, it triggered a sequence of events leading to one of the worst releases of radioactive materials in the world to date. Although nuclear energy is having a revival as a low-emissions energy source to mitigate climate change, the Fukushima accident is still cited as a reason for hesitancy in adopting it.

      A new study synthesizes information from multidisciplinary sources to understand how the Fukushima Dai’ichi disaster unfolded, and points to the importance of mitigation measures and last lines of defense — even against accidents considered highly unlikely. These procedures have received relatively little attention, but they are critical in determining how severe the consequences of a reactor failure will be, the researchers say.

      The researchers note that their synthesis is one of the few attempts to look at data across disciplinary boundaries, including: the physics and engineering of what took place within the plant’s systems, the plant operators’ actions throughout the emergency, actions by emergency responders, the meteorology of radionuclide releases and transport, and the environmental and health consequences documented since the event.

      The study appears in the journal iScience, in an open-access paper by postdoc Ali Ayoub and Professor Haruko Wainwright at MIT, along with others in Switzerland, Japan, and New Mexico.

      Since 2013, Wainwright has been leading the research to integrate all the radiation monitoring data in the Fukushima region into integrated maps. “I was staring at the contamination map for nearly 10 years, wondering what created the main plume extending in the northwest direction, but I could not find exact information,” Wainwright says. “Our study is unique because we started from the consequence, the contamination map, and tried to identify the key factors for the consequence. Other people study the Fukushima accident from the root cause, the tsunami.”

      One thing they found was that while all the operating reactors, units 1, 2, and 3, suffered core meltdowns as a result of the failure of emergency cooling systems, units 1 and 3 — although they did experience hydrogen explosions — did not release as much radiation to the environment because their venting systems essentially worked to relieve pressure inside the containment vessels as intended. But the same system in unit 2 failed badly.

      “People think that the hydrogen explosion or the core meltdown were the worst things, or the major driver of the radiological consequences of the accident,” Wainright says, “but our analysis found that’s not the case.” Much more significant in terms of the radiological release was the failure of the one venting mechanism.

      “There is a pressure-release mechanism that goes through water where a lot of the radionuclides get filtered out,” she explains. That system was effective in units 1 and 3, filtering out more than 90 percent of the radioactive elements before the gas was vented. However, “in unit 2, that pressure release mechanism got stuck, and the operators could not manually open it.” A hydrogen explosion in unit 1 had damaged the pressure relief mechanism of unit 2. This led to a breach of the containment structure and direct, unfiltered venting to the atmosphere, which, according to the new study, was what produced the greatest amount of contamination from the whole weeks-long event.

      Another factor was the timing of the attempt to vent the pressure buildup in the reactor. Guidelines at the time, and to this day in many reactors, specified that no venting should take place until the pressure inside the reactor containment vessel reached a specified threshold, with no regard to the wind directions at the time. In the case of Fukushima, an earlier venting could have dramatically reduced the impact: Much of the release happened when winds were blowing directly inland, but earlier the wind had been blowing offshore.

      “That pressure-release mechanism has not been a major focus of the engineering community,” she says. While there is appropriate attention to measures that prevent a core meltdown in the first place, “this sort of last line of defense has not been the main focus and should get more attention.”

      Wainwright says the study also underlines several successes in the management of the Fukushima accident. Many of the safety systems did work as they were designed. For example, even though the oldest reactor, unit 1, suffered the greatest internal damage, it released little radioactive material. Most people were able to evacuate from the 20-kilometer (12-mile) zone before the largest release happened. The mitigation measures were “somewhat successful,” Wainwright says. But there was tremendous confusion and anger during and after the accident because there were no preparations in place for such an event.

      Much work has focused on ways to prevent the kind of accidents that happened at Fukushima — for example, in the U.S. reactor operators can deploy portable backup power supplies to maintain proper reactor cooling at any reactor site. But the ongoing situation at the Zaporizhzhia nuclear complex in Ukraine, where nuclear safety is challenged by acts of war, demonstrates that despite engineers’ and operators’ best efforts to prevent it, “the totally unexpected could still happen,” Wainwright says.

      “The big-picture message is that we should have equal attention to both prevention and mitigation of accidents,” she says. “This is the essence of resilience, and it applies beyond nuclear power plants to all essential infrastructure of a functioning society, for example, the electric grid, the food and water supply, the transportation sector, etc.”

      One thing the researchers recommend is that in designing evacuation protocols, planners should make more effort to learn from much more frequent disasters such as wildfires and hurricanes. “We think getting more interdisciplinary, transdisciplinary knowledge from other kinds of disasters would be essential,” she says. Most of the emergency response strategies presently in place, she says, were designed in the 1980s and ’90s, and need to be modernized. “Consequences can be mitigated. A nuclear accident does not have to be a catastrophe, as is often portrayed in popular culture,” Wainright says.

      The research team included Giovanni Sansavini at ETH Zurich in Switzerland; Randall Gauntt at Sandia National Laboratories in New Mexico; and Kimiaki Saito at the Japan Atomic Energy Agency. More

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      in Environment

      Study finds lands used for grazing can worsen or help climate change

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      When it comes to global climate change, livestock grazing can be either a blessing or a curse, according to a new study, which offers clues on how to tell the difference.

      If managed properly, the study shows, grazing can actually increase the amount of carbon from the air that gets stored in the ground and sequestered for the long run. But if there is too much grazing, soil erosion can result, and the net effect is to cause more carbon losses, so that the land becomes a net carbon source, instead of a carbon sink. And the study found that the latter is far more common around the world today.

      The new work, published today in the journal Nature Climate Change, provides ways to determine the tipping point between the two, for grazing lands in a given climate zone and soil type. It also provides an estimate of the total amount of carbon that has been lost over past decades due to livestock grazing, and how much could be removed from the atmosphere if grazing optimization management implemented. The study was carried out by Cesar Terrer, an assistant professor of civil and environmental engineering at MIT; Shuai Ren, a PhD student at the Chinese Academy of Sciences whose thesis is co-supervised by Terrer; and four others.

      “This has been a matter of debate in the scientific literature for a long time,” Terrer says. “In general experiments, grazing decreases soil carbon stocks, but surprisingly, sometimes grazing increases soil carbon stocks, which is why it’s been puzzling.”

      What happens, he explains, is that “grazing could stimulate vegetation growth through easing resource constraints such as light and nutrients, thereby increasing root carbon inputs to soils, where carbon can stay there for centuries or millennia.”

      But that only works up to a certain point, the team found after a careful analysis of 1,473 soil carbon observations from different grazing studies from many locations around the world. “When you cross a threshold in grazing intensity, or the amount of animals grazing there, that is when you start to see sort of a tipping point — a strong decrease in the amount of carbon in the soil,” Terrer explains.

      That loss is thought to be primarily from increased soil erosion on the denuded land. And with that erosion, Terrer says, “basically you lose a lot of the carbon that you have been locking in for centuries.”

      The various studies the team compiled, although they differed somewhat, essentially used similar methodology, which is to fence off a portion of land so that livestock can’t access it, and then after some time take soil samples from within the enclosure area, and from comparable nearby areas that have been grazed, and compare the content of carbon compounds.

      “Along with the data on soil carbon for the control and grazed plots,” he says, “we also collected a bunch of other information, such as the mean annual temperature of the site, mean annual precipitation, plant biomass, and properties of the soil, like pH and nitrogen content. And then, of course, we estimate the grazing intensity — aboveground biomass consumed, because that turns out to be the key parameter.”  

      With artificial intelligence models, the authors quantified the importance of each of these parameters, those drivers of intensity — temperature, precipitation, soil properties — in modulating the sign (positive or negative) and magnitude of the impact of grazing on soil carbon stocks. “Interestingly, we found soil carbon stocks increase and then decrease with grazing intensity, rather than the expected linear response,” says Ren.

      Having developed the model through AI methods and validated it, including by comparing its predictions with those based on underlying physical principles, they can then apply the model to estimating both past and future effects. “In this case,” Terrer says, “we use the model to quantify the historical loses in soil carbon stocks from grazing. And we found that 46 petagrams [billion metric tons] of soil carbon, down to a depth of one meter, have been lost in the last few decades due to grazing.”

      By way of comparison, the total amount of greenhouse gas emissions per year from all fossil fuels is about 10 petagrams, so the loss from grazing equals more than four years’ worth of all the world’s fossil emissions combined.

      What they found was “an overall decline in soil carbon stocks, but with a lot of variability.” Terrer says. The analysis showed that the interplay between grazing intensity and environmental conditions such as temperature could explain the variability, with higher grazing intensity and hotter climates resulting in greater carbon loss. “This means that policy-makers should take into account local abiotic and biotic factors to manage rangelands efficiently,” Ren notes. “By ignoring such complex interactions, we found that using IPCC [Intergovernmental Panel on Climate Change] guidelines would underestimate grazing-induced soil carbon loss by a factor of three globally.”

      Using an approach that incorporates local environmental conditions, the team produced global, high-resolution maps of optimal grazing intensity and the threshold of intensity at which carbon starts to decrease very rapidly. These maps are expected to serve as important benchmarks for evaluating existing grazing practices and provide guidance to local farmers on how to effectively manage their grazing lands.

      Then, using that map, the team estimated how much carbon could be captured if all grazing lands were limited to their optimum grazing intensity. Currently, the authors found, about 20 percent of all pasturelands have crossed the thresholds, leading to severe carbon losses. However, they found that under the optimal levels, global grazing lands would sequester 63 petagrams of carbon. “It is amazing,” Ren says. “This value is roughly equivalent to a 30-year carbon accumulation from global natural forest regrowth.”

      That would be no simple task, of course. To achieve optimal levels, the team found that approximately 75 percent of all grazing areas need to reduce grazing intensity. Overall, if the world seriously reduces the amount of grazing, “you have to reduce the amount of meat that’s available for people,” Terrer says.

      “Another option is to move cattle around,” he says, “from areas that are more severely affected by grazing intensity, to areas that are less affected. Those rotations have been suggested as an opportunity to avoid the more drastic declines in carbon stocks without necessarily reducing the availability of meat.”

      This study didn’t delve into these social and economic implications, Terrer says. “Our role is to just point out what would be the opportunity here. It shows that shifts in diets can be a powerful way to mitigate climate change.”

      “This is a rigorous and careful analysis that provides our best look to date at soil carbon changes due to livestock grazing practiced worldwide,” say Ben Bond-Lamberty, a terrestrial ecosystem research scientist at Pacific Northwest National Laboratory, who was not associated with this work. “The authors’ analysis gives us a unique estimate of soil carbon losses due to grazing and, intriguingly, where and how the process might be reversed.”

      He adds: “One intriguing aspect to this work is the discrepancies between its results and the guidelines currently used by the IPCC — guidelines that affect countries’ commitments, carbon-market pricing, and policies.” However, he says, “As the authors note, the amount of carbon historically grazed soils might be able to take up is small relative to ongoing human emissions. But every little bit helps!”

      “Improved management of working lands can be a powerful tool to combat climate change,” says Jonathan Sanderman, carbon program director of the Woodwell Climate Research Center in Falmouth, Massachusetts, who was not associated with this work. He adds, “This work demonstrates that while, historically, grazing has been a large contributor to climate change, there is significant potential to decrease the climate impact of livestock by optimizing grazing intensity to rebuild lost soil carbon.”

      Terrer states that for now, “we have started a new study, to evaluate the consequences of shifts in diets for carbon stocks. I think that’s the million-dollar question: How much carbon could you sequester, compared to business as usual, if diets shift to more vegan or vegetarian?” The answers will not be simple, because a shift to more vegetable-based diets would require more cropland, which can also have different environmental impacts. Pastures take more land than crops, but produce different kinds of emissions. “What’s the overall impact for climate change? That is the question we’re interested in,” he says.

      The research team included Juan Li, Yingfao Cao, Sheshan Yang, and Dan Liu, all with the  Chinese Academy of Sciences. The work was supported by the Second Tibetan Plateau Scientific Expedition and Research Program, and the Science and Technology Major Project of Tibetan Autonomous Region of China. More

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      in Energy

      Explained: Carbon credits

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      One of the most contentious issues faced at the 28th Conference of Parties (COP28) on climate change last December was a proposal for a U.N.-sanctioned market for trading carbon credits. Such a mechanism would allow nations and industries making slow progress in reducing their own carbon emissions to pay others to take emissions-reducing measures, such as improving energy efficiency or protecting forests.

      Such trading systems have already grown to a multibillion-dollar market despite a lack of clear international regulations to define and monitor the claimed emissions reductions. During weeks of feverish negotiations, some nations, including the U.S., advocated for a somewhat looser approach to regulations in the interests of getting a system in place quickly. Others, including the European Union, advocated much tighter regulation, in light of a history of questionable or even counterproductive projects of this kind in the past. In the end, no agreement was reached on the subject, which will be revisited at a later meeting.

      The concept seems simple enough: Offset emissions in one place by preventing or capturing an equal amount of emissions elsewhere. But implementing that idea has turned out to be far more complex and fraught with problems than many expected.

      For example, projects that aim to preserve a section of forest — which can remove carbon dioxide from the air and sequester it in the soil — face numerous issues. Will the preservation of one parcel just lead to the clearcutting of an adjacent parcel? Would the preserved land have been left uncut anyway? And what if it ends up being destroyed by wildfire, drought, or insect infestation — all of which are expected to become more likely with climate change?

      Similarly, projects that aim to capture carbon dioxide emissions and inject them into the ground are sometimes used to justify increasing the production of petroleum or natural gas, negating the intended climate mitigation of the process.

      Several experts at MIT now say that the system could be effective, at least in certain circumstances, but it must be thoroughly evaluated and regulated.

      Carbon removal, natural or mechanical

      Sergey Paltsev, deputy director of MIT’s Joint Program on the Science and Policy of Global Change, co-led a study and workshop last year that included policymakers, industry representatives, and researchers. They focused on one kind of carbon offsets, those based on natural climate solutions — restoration or preservation of natural systems that not only sequester carbon but also provide other benefits, such as greater biodiversity. “We find a lot of confusion and misperceptions and misinformation, even about how you define the term carbon credit or offset,” he says.

      He points out that there has been a lot of criticism of the whole idea of carbon offsets, “and that criticism is well-placed. I think that’s a very healthy conversation, to clarify what makes sense and what doesn’t make sense. What are the real actions versus what is greenwashing?”

      He says that government-mandated and managed carbon trading programs in some places, including British Columbia and parts of Europe, have been somewhat effective because they have clear standards in place, whereas unregulated carbon credit systems have often been abused.

      Charles Harvey, an MIT professor of civil and environmental engineering, should know, having been actively involved in both sides of the issue over the last two decades. He co-founded a company in 2008 that was the first private U.S. company to attempt to remove carbon dioxide from emissions on a commercial scale, a process called carbon capture and sequestration, or CCS. Such projects have been a major recipient of federal subsidies aimed at combatting climate change, but Harvey now says these are largely a waste of money and in most cases do not achieve their stated objective.

      In fact, he says that according to industry sources, as of 2021 more than 90 percent of CCS projects in the U.S. have been used for the production of more fossil fuels — oil and natural gas. Here’s how it works: Natural gas wells often produce methane mixed with carbon dioxide, which must be removed to produce a marketable natural gas. This carbon dioxide is then injected into oil wells to stimulate more production. So, the net effect is the creation of more total greenhouse gas emissions rather than less, explains Harvey, who recently received a grant from the Rockefeller Foundation to explore CCS projects and whether they can be made to contribute to true emissions reductions.

      What went wrong with the ambitious startup CCS company Harvey co-founded? “What happened is that the prices of renewables and energy storage are now incredibly cheap,” he says. “It makes no sense to do this, ever, on power plants because honestly, fossil fuel power plants don’t even really make economic sense anymore.”

      Where does Harvey see potential for carbon credits to work? One possibility is the preservation or restoration of tropical peatlands, which he has received another grant to study. These are vast areas of permanently waterlogged land in which dead plant matter —and the carbon it contains — remains in place because the water prevents the normal decomposition processes that would otherwise release the stored carbon back into the air.

      While it is virtually impossible to quantify the amount of carbon stored in the soil of forest or farmland, in peatlands that’s easy to do because essentially all of the submerged material is carbon-based. Simply measuring changes in the elevation of such land, which can be done remotely by plane or satellite, gives a precise measure of how much carbon has been stored or released. When a patch of peat forest that has been clear-cut to build plantations or roads is reforested, the amount of carbon emissions that were prevented can be measured accurately.

      Because of that potential for accurate documentation, protecting or restoring peat bogs can also be a good way to achieve meaningful offsets for carbon emissions elsewhere, Harvey says. Rewetting a previously drained peat forest can immediately counteract the release of its stored carbon and can keep it there as long as it is not drained again — something that can be verified using satellite data.

      Paltsev adds that while such nature-based systems for countering carbon emissions can be a key component of addressing climate change, especially in very difficult-to-decarbonize industries such as aviation, carbon credits for such programs “shouldn’t be a replacement for our efforts at emissions reduction. It should be in addition.”

      Criteria for meaningful offsets

      John Sterman, the Jay W. Forrester Professor of Management at the MIT Sloan School of Management, has published a set of criteria for evaluating proposed carbon offset plans to make sure they would provide the benefits they claim. At present, “there’s no regulation, there’s no oversight” for carbon offsets, he says. “There have been many scandals over this.”

      For example, one company was providing what it claimed was certification for carbon offset projects but was found to have such lax standards that the claimed offsets were often not real. For example, there were multiple claims to protect the same piece of forest and claims to protect land that was already legally protected.

      Sterman’s proposed set of criteria goes by the acronym AVID+. “It stands for four principles that you have to meet in order for your offset to be legitimate: It has to be additional, verifiable, immediate, and durable,” he says. “And then I call it AVID+,” he adds, the “plus” being for plans that have additional benefits as well, such as improving health, creating jobs, or helping historically disadvantaged communities.

      Offsets can be useful, he says, for addressing especially hard-to-abate industries such as steel or cement manufacturing, or aviation. But it is essential to meet all four of the criteria, or else real emissions are not really being offset. For example, planting trees today, while often a good thing to do, would take decades to offset emissions going into the atmosphere now, where they may persist for centuries — so that fails to meet the “immediate” requirement.

      And protecting existing forests, while also desirable, is very hard to prove as being additional, because “that requires a counterfactual that you can never observe,” he says. “That’s where a lot of squirrely accounting and a lot of fraud comes in, because how do you know that the forest would have been cut down but for the offset?” In one well-documented case, he points out, a company tried to sell carbon offsets for a section of forest that was already an established nature preserve.

      Are there offsets that can meet all the criteria and provide real benefits in helping to address climate change? Yes, Sterman and Harvey say, but they need to be evaluated carefully.

      “My favorite example,” Sterman says, “is doing deep energy retrofits and putting solar panels on low-income housing.” These measures can help address the so-called landlord-tenant problem: If tenants typically pay the utility bills, landlords have little incentive to pay for efficiency improvements, and the tenants don’t have the capital to make such improvements on their own. “Policies that would make this possible are pretty good candidates for legitimate offsets, because they are additional — low-income households can’t afford to do it without assistance, so it’s not going to happen without a program. It’s verifiable, because you’ve got the utility bills pre and post.” They are also quite immediate, typically taking only a year or so to implement, and “they’re pretty durable,” he says.

      Another example is a recent plan in Alaska that allows cruise ships to offset the emissions caused by their trips by paying into a fund that provides subsidies for Alaskan citizens to install heat pumps in their homes, thus preventing emissions from wood or fossil fuel heating systems. “I think this is a pretty good candidate to meet the criteria, certainly a lot better than much of what’s being done today,” Sterman says.

      But eventually, what is really needed, the researchers agree, are real, enforceable standards. After COP28, carbon offsets are still allowed, Sterman says, “but there is still no widely accepted mandatory regulation. We’re still in the wild West.”

      Paltsev nevertheless sees reasons for optimism about nature-based carbon offset systems. For example, he says the aviation industry has recently agreed to implement a set of standards for offsetting their emissions, known as CORSIA, for carbon offsetting and reduction scheme for international aviation. “It’s a point for optimism,” he says, “because they issued very tough guidelines as to what projects are eligible and what projects are not.”

      He adds, “There is a solution if you want to find a good solution. It is doable, when there is a will and there is the need.” More

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      in Environment

      Satellite-based method measures carbon in peat bogs

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      Peat bogs in the tropics store vast amounts of carbon, but logging, plantations, road building, and other activities have destroyed large swaths of these ecosystems in places like Indonesia and Malaysia. Peat formations are essentially permanently flooded forestland, where dead leaves and branches accumulate because the water table prevents their decomposition.

      The pileup of organic material gives these formations a distinctive domed shape, somewhat raised in the center and tapering toward the edges. Determining how much carbon is contained in each formation has required laborious on-the-ground sampling, and so has been limited in its coverage.

      Now, researchers from MIT and Singapore have developed a mathematical analysis of how peat formations build and develop, that makes it possible to evaluate their carbon content and dynamics mostly from simple elevation measurements. These can be carried out by satellites, without requiring ground-based sampling. This analysis, the team says, should make it possible to make more precise and accurate assessments of the amount of carbon that would be released by any proposed draining of peatlands — and, inversely, how much carbon emissions could be avoided by protecting them.

      The research is being reported today in the journal Nature, in a paper by Alexander Cobb, a postdoc with the Singapore-MIT Alliance for Research and Technology (SMART); Charles Harvey, an MIT professor of civil and environmental engineering; and six others.

      Although it is the tropical peatlands that are at greatest risk — because they are the ones most often drained for timber harvesting or the creation of plantations for palm oil, acacia, and other crops — the new formulas the team derived apply to peatlands all over the globe, from Siberia to New Zealand. The formula requires just two inputs. The first is elevation data from a single transect of a given peat dome — that is, a series of elevation measurements along an arbitrary straight line cutting across from one edge of the formation to the other. The second input is a site-specific factor the team devised that relates to the type of peat bog involved and the internal structure of the formation, which together determine how much of the carbon within remains safely submerged in water, where it can’t be oxidized.

      “The saturation by water prevents oxygen from getting in, and if oxygen gets in, microbes breathe it and eat the peat and turn it into carbon dioxide,” Harvey explains.

      “There is an internal surface inside the peat dome below which the carbon is safe because it can’t be drained, because the bounding rivers and water bodies are such that it will keep saturated up to that level even if you cut canals and try to drain it,” he adds. In between the visible surface of the bog and this internal layer is the “vulnerable zone” of peat that can rapidly decompose and release its carbon compounds or become dry enough to promote fires that also release the carbon and pollute the air.

      Through years of on-the-ground sampling and testing, and detailed analysis comparing the ground data with satellite lidar data on surface elevations, the team was able to figure out a kind of universal mathematical formula that describes the structure of peat domes of all kinds and in all locations. They tested it by comparing their predicted results with field measurements from several widely distributed locations, including Alaska, Maine, Quebec, Estonia, Finland, Brunei, and New Zealand.

      These bogs contain carbon that has in many cases accumulated over thousands of years but can be released in just a few years when the bogs are drained. “If we could have policies to preserve these, it is a tremendous opportunity to reduce carbon fluxes to the atmosphere. This framework or model gives us the understanding, the intellectual framework, to figure out how to do that,” Harvey says.

      Many people assume that the biggest greenhouse gas emissions from cutting down these forested lands is from the decomposition of the trees themselves. “The misconception is that that’s the carbon that goes to the atmosphere,” Harvey says. “It’s actually a small amount, because the real fluxes to the atmosphere come from draining” the peat bogs. “Then, the much larger pool of carbon, which is underground beneath the forest, oxidizes and goes to the air, or catches fire and burns.”

      But there is hope, he says, that much of this drained peatland can still be restored before the stored carbon all gets released. First of all, he says, “you’ve got to stop draining it.” That can be accomplished by damming up the drainage canals. “That’s what’s good about this mathematical framework: You need to figure out how to do that, where to put your dams. There’s all sorts of interesting complexities. If you just dam up the canal, the water may flow around it. So, it’s a neat geometric and engineering project to figure out how to do this.”

      While much of the peatland in southeast Asia has already been drained, the new analysis should make it possible to make much more accurate assessments of less-well-studied peatlands in places like the Amazon basin, New Guinea and the Congo basin, which are also threatened by development.

      The new formulation should also help to make some carbon offset programs more reliable, because it is now possible to calculate accurately the carbon content of a given peatland. “It’s quantifiable, because the peat is 100 percent organic carbon. So, if you just measure the change in the surface going up or down, you can say with pretty good certainty how much carbon has been accumulated or lost, whereas if you go to a rainforest, it’s virtually impossible to calculate the amount of underground carbon, and it’s pretty hard to calculate what’s above ground too,” Harvey says. “But this is relatively easy to calculate with satellite measurements of elevation.”

      “We can turn the knob,” he says, “because we have this mathematical framework for how the hydrology, the water table position, affects the growth and loss of peat. We can design a scheme that will change emissions by X amount, for Y dollars.”

      The research team included Rene Dommain, Kimberly Yeap, and Cao Hannan at Nanyang Technical University in Singapore, Nathan Dadap at Stanford University, Bodo Bookhagen at the University of Potsdam, Germany, and Paul Glaser at the University of Minnesota. The work was supported by the National Research Foundation Singapore through the SMART program, by the U.S. National Science Foundation, and Singapore’s Office for Space Technology and Industry. More

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      in Environment

      Unlocking the secrets of natural materials

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      Growing up in Milan, Benedetto Marelli liked figuring out how things worked. He repaired broken devices simply to have the opportunity to take them apart and put them together again. Also, from a young age, he had a strong desire to make a positive impact on the world. Enrolling at the Polytechnic University of Milan, he chose to study engineering.

      “Engineering seemed like the right fit to fulfill my passions at the intersection of discovering how the world works, together with understanding the rules of nature and harnessing this knowledge to create something new that could positively impact our society,” says Marelli, MIT’s Paul M. Cook Career Development Associate Professor of Civil and Environmental Engineering.

      Marelli decided to focus on biomedical engineering, which at the time was the closest thing available to biological engineering. “I liked the idea of pursuing studies that provided me a background to engineer life,” in order to improve human health and agriculture, he says.

      Marelli went on to earn a PhD in materials science and engineering at McGill University and then worked in Tufts University’s biomaterials Silklab as a postdoc. After his postdoc, Marelli was drawn to MIT’s Department of Civil and Environmental in large part because of the work of Markus Buehler, MIT’s McAfee Professor of Engineering, who studies how to design new materials by understanding the architecture of natural ones.

      “This resonated with my training and idea of using nature’s building blocks to build a more sustainable society,” Marelli says. “It was a big leap forward for me to go from biomedical engineering to civil and environmental engineering. It meant completely changing my community, understanding what I could teach and how to mentor students in a new engineering branch. As Markus is working with silk to study how to engineer better materials, this made me see a clear connection with what I was doing and what I could be doing. I consider him one of my mentors here at MIT and was fortunate to end up collaborating with him.”

      Marelli’s research is aimed at mitigating several pressing global problems, he says.

      “Boosting food production to provide food security to an ever-increasing population, soil restoration, decreasing the environmental impact of fertilizers, and addressing stressors coming from climate change are societal challenges that need the development of rapidly scalable and deployable technologies,” he says.

      Marelli and his fellow researchers have developed coatings derived from natural silk that extend the shelf life of food, deliver biofertilizers to seeds planted in salty, unproductive soils, and allow seeds to establish healthier plants and increase crop yield in drought-stricken lands. The technologies have performed well in field tests being conducted in Morocco in collaboration with the Mohammed VI Polytechnic University in Ben Guerir, according to Marelli, and offer much potential.

      “I believe that with this technology, together with the common efforts shared by the MIT PIs participating in the Climate Grand Challenge on Revolutionizing Agriculture, we have a  real opportunity to positively impact planetary health and find new solutions that work in both rural settings and highly modernized agricultural fields,” says Marelli, who recently earned tenure.

      As a researcher and entrepreneur with about 20 patents to his name and awards including a National Science Foundation CAREER award, the Presidential Early Career Award for Scientists and Engineers award, and the Ole Madsen Mentoring Award, Marelli says that in general his insights into structural proteins — and how to use that understanding to manufacture advanced materials at multiple scales — are among his proudest achievements.

      More specifically, Marelli cites one of his breakthroughs involving a strawberry. Having dipped the berry in an odorless, tasteless edible silk suspension as part of a cooking contest held in his postdoctoral lab, he accidentally left it on his bench, only to find a week or so later that it had been well-preserved.

      “The coating of the strawberry to increase its shelf life is difficult to beat when it comes to inspiring people that natural polymers can serve as technical materials that can positively impact our society” by lessening food waste and the need for energy-intensive refrigerated shipping, Marelli says.

      When Marelli won the BioInnovation Institute and Science Prize for Innovation in 2022, he told the journal Science that he thinks students should be encouraged to choose an entrepreneurial path. He acknowledged the steepness of the learning curve of being an entrepreneur but also pointed out how the impact of research can be exponentially increased.

      He expanded on this idea more recently.

      “I believe an increasing number of academics and graduate students should try to get their hands ‘dirty’ with entrepreneurial efforts. We live in a time where academics are called to have a tangible impact on our society, and translating what we study in our labs is clearly a good way to employ our students and enhance the global effort to develop new technology that can make our society more sustainable and equitable,” Marelli says.

      Referring to a spinoff company, Mori, that grew out of the coated strawberry discovery and that develops silk-based products to preserve a wide range of perishable foods, Marelli says he finds it very satisfying to know that Mori has a product on the market that came out of his research efforts — and that 80 people are working to translate the discovery from “lab to fork.”

      “Knowing that the technology can move the needle in crises such as food waste and food-related environmental impact is the highest reward of all,” he says.

      Marelli says he tells students who are seeking solutions to extremely complicated problems to come up with one solution, “however crazy it might be,” and then do an extensive literature review to see what other researchers have done and whether “there is any hint that points toward developing their solution.”

      “Once we understand the feasibility, I typically work with them to simplify it as much as we can, and then to break down the problem in small parts that are addressable in series and/or in parallel,” Marelli says.

      That process of discovery is ongoing. Asked which of his technologies will have the greatest impact on the world, Marelli says, “I’d like to think it’s the ones that still need to be discovered.” More

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      in Environment

      Forging climate connections across the Institute

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      Climate change is the ultimate cross-cutting issue: Not limited to any one discipline, it ranges across science, technology, policy, culture, human behavior, and well beyond. The response to it likewise requires an all-of-MIT effort.

      Now, to strengthen such an effort, a new grant program spearheaded by the Climate Nucleus, the faculty committee charged with the oversight and implementation of Fast Forward: MIT’s Climate Action Plan for the Decade, aims to build up MIT’s climate leadership capacity while also supporting innovative scholarship on diverse climate-related topics and forging new connections across the Institute.

      Called the Fast Forward Faculty Fund (F^4 for short), the program has named its first cohort of six faculty members after issuing its inaugural call for proposals in April 2023. The cohort will come together throughout the year for climate leadership development programming and networking. The program provides financial support for graduate students who will work with the faculty members on the projects — the students will also participate in leadership-building activities — as well as $50,000 in flexible, discretionary funding to be used to support related activities. 

      “Climate change is a crisis that truly touches every single person on the planet,” says Noelle Selin, co-chair of the nucleus and interim director of the Institute for Data, Systems, and Society. “It’s therefore essential that we build capacity for every member of the MIT community to make sense of the problem and help address it. Through the Fast Forward Faculty Fund, our aim is to have a cohort of climate ambassadors who can embed climate everywhere at the Institute.”

      F^4 supports both faculty who would like to begin doing climate-related work, as well as faculty members who are interested in deepening their work on climate. The program has the core goal of developing cohorts of F^4 faculty and graduate students who, in addition to conducting their own research, will become climate leaders at MIT, proactively looking for ways to forge new climate connections across schools, departments, and disciplines.

      One of the projects, “Climate Crisis and Real Estate: Science-based Mitigation and Adaptation Strategies,” led by Professor Siqi Zheng of the MIT Center for Real Estate in collaboration with colleagues from the MIT Sloan School of Management, focuses on the roughly 40 percent of carbon dioxide emissions that come from the buildings and real estate sector. Zheng notes that this sector has been slow to respond to climate change, but says that is starting to change, thanks in part to the rising awareness of climate risks and new local regulations aimed at reducing emissions from buildings.

      Using a data-driven approach, the project seeks to understand the efficient and equitable market incentives, technology solutions, and public policies that are most effective at transforming the real estate industry. Johnattan Ontiveros, a graduate student in the Technology and Policy Program, is working with Zheng on the project.

      “We were thrilled at the incredible response we received from the MIT faculty to our call for proposals, which speaks volumes about the depth and breadth of interest in climate at MIT,” says Anne White, nucleus co-chair and vice provost and associate vice president for research. “This program makes good on key commitments of the Fast Forward plan, supporting cutting-edge new work by faculty and graduate students while helping to deepen the bench of climate leaders at MIT.”

      During the 2023-24 academic year, the F^4 faculty and graduate student cohorts will come together to discuss their projects, explore opportunities for collaboration, participate in climate leadership development, and think proactively about how to deepen interdisciplinary connections among MIT community members interested in climate change.

      The six inaugural F^4 awardees are:

      Professor Tristan Brown, History Section: Humanistic Approaches to the Climate Crisis  

      With this project, Brown aims to create a new community of practice around narrative-centric approaches to environmental and climate issues. Part of a broader humanities initiative at MIT, it brings together a global working group of interdisciplinary scholars, including Serguei Saavedra (Department of Civil and Environmental Engineering) and Or Porath (Tel Aviv University; Religion), collectively focused on examining the historical and present links between sacred places and biodiversity for the purposes of helping governments and nongovernmental organizations formulate better sustainability goals. Boyd Ruamcharoen, a PhD student in the History, Anthropology, and Science, Technology, and Society (HASTS) program, will work with Brown on this project.

      Professor Kerri Cahoy, departments of Aeronautics and Astronautics and Earth, Atmospheric, and Planetary Sciences (AeroAstro): Onboard Autonomous AI-driven Satellite Sensor Fusion for Coastal Region Monitoring

      The motivation for this project is the need for much better data collection from satellites, where technology can be “20 years behind,” says Cahoy. As part of this project, Cahoy will pursue research in the area of autonomous artificial intelligence-enabled rapid sensor fusion (which combines data from different sensors, such as radar and cameras) onboard satellites to improve understanding of the impacts of climate change, specifically sea-level rise and hurricanes and flooding in coastal regions. Graduate students Madeline Anderson, a PhD student in electrical engineering and computer science (EECS), and Mary Dahl, a PhD student in AeroAstro, will work with Cahoy on this project.

      Professor Priya Donti, Department of Electrical Engineering and Computer Science: Robust Reinforcement Learning for High-Renewables Power Grids 

      With renewables like wind and solar making up a growing share of electricity generation on power grids, Donti’s project focuses on improving control methods for these distributed sources of electricity. The research will aim to create a realistic representation of the characteristics of power grid operations, and eventually inform scalable operational improvements in power systems. It will “give power systems operators faith that, OK, this conceptually is good, but it also actually works on this grid,” says Donti. PhD candidate Ana Rivera from EECS is the F^4 graduate student on the project.

      Professor Jason Jackson, Department of Urban Studies and Planning (DUSP): Political Economy of the Climate Crisis: Institutions, Power and Global Governance

      This project takes a political economy approach to the climate crisis, offering a distinct lens to examine, first, the political governance challenge of mobilizing climate action and designing new institutional mechanisms to address the global and intergenerational distributional aspects of climate change; second, the economic challenge of devising new institutional approaches to equitably finance climate action; and third, the cultural challenge — and opportunity — of empowering an adaptive socio-cultural ecology through traditional knowledge and local-level social networks to achieve environmental resilience. Graduate students Chen Chu and Mrinalini Penumaka, both PhD students in DUSP, are working with Jackson on the project.

      Professor Haruko Wainwright, departments of Nuclear Science and Engineering (NSE) and Civil and Environmental Engineering: Low-cost Environmental Monitoring Network Technologies in Rural Communities for Addressing Climate Justice 

      This project will establish a community-based climate and environmental monitoring network in addition to a data visualization and analysis infrastructure in rural marginalized communities to better understand and address climate justice issues. The project team plans to work with rural communities in Alaska to install low-cost air and water quality, weather, and soil sensors. Graduate students Kay Whiteaker, an MS candidate in NSE, and Amandeep Singh, and MS candidate in System Design and Management at Sloan, are working with Wainwright on the project, as is David McGee, professor in earth, atmospheric, and planetary sciences.

      Professor Siqi Zheng, MIT Center for Real Estate and DUSP: Climate Crisis and Real Estate: Science-based Mitigation and Adaptation Strategies 

      See the text above for the details on this project. More

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      in Environment

      Bringing the environment to the forefront of engineering

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      In a recent podcast interview with MIT President Sally Kornbluth, Associate Professor Desirée Plata described her childhood pastime of roaming the backyards and businesses of her grandmother’s hometown of Gray, Maine. Through her wanderings, Plata noticed a disturbing pattern.

      “I was 7 or 8 when I caught wind of all the illness,” Plata recalls. “It seemed like in every other house there was somebody who had a neurological disorder or a cancer of some sort.”

      While driving home one night with her mom, Plata made her first environmental hypothesis from the back seat. “I told my mom, ‘I think there’s something in the water or air where these people live.’”

      The conversation happened in the late 1980s. Plata was a little older when she learned her intuition was correct: The Environmental Protection Agency determined that a waste disposal facility had contaminated drinking water in the area while processing more than 1 million gallons of waste between 1965 and 1978.

      “There was a New York Times article on it, but it was sort of buried in a Sunday paper and a lot of folks up in Maine didn’t hear about it,” Plata says.

      What most struck Plata was that Gray was a tight-knit community, and the people who owned the waste disposal facility were friends with everybody. Eventually, some of the owner’s children even got sick.

      “People don’t poison their neighbors on purpose,” Plata says. “A lot of industrial contamination happens either by accident or because the engineers don’t know better. As an environmental scientist and engineer, it’s part of my job to help industrial engineers of any variety design their systems and processes such that they are thinking about what’s going into the environment from the start.”

      The insight led Plata to MIT, first as a PhD student, then as a visiting professor, and today as the newly tenured associate professor of civil and environmental engineering.

      These days Plata’s work is a bit more complex than her early backseat musings. In fact, her efforts extend far beyond research and include mentoring students, entrepreneurship, coalition-building, and coordination across industry, academia, and government. But the work can still be traced back to the childhood insight that environmental optimization needs to be a more tangible and important part of everyone’s thinking.

      “People think sustainability is this nebulous thing they can’t get their hands around,” Plata says. “But there are actually a set of rigorous principles you can use, and each one of those has a metric or a thing you can measure to go with it. MIT is such an innovative place. If we can incorporate environmental objectives into design at a place like MIT, the hope is the world can engage as well.”

      Taking the plunge

      Plata was first introduced to environmental research in high school, but it wasn’t until she attended Union College and got to work in a research lab that she knew it was what she’d do for the rest of her life.

      After graduating from Union, Plata decided to skip a master’s degree and “take the plunge” into the MIT-Woods Hole Oceanographic Institution (WHOI) joint doctoral program.

      “Talk about drinking from a firehose,” Plata says. “Everybody you bump into knows something that can help you solve the very hard problem you’re working on.”

      Plata began the program studying oil spills, and a paper she co-authored helped spur a law that changed the way oil is transported off the coast of Massachusetts. But developments in her personal life made her want to prevent environmental disasters before they happen.

      In her last year at Union, Plata’s aunt was diagnosed with breast cancer — a disease that’s been linked to one of the chemicals dumped in Gray, Maine. While Plata was at MIT, her aunt was receiving treatment at Massachusetts General Hospital down the road, so Plata would work at the lab at night, stay with her aunt during treatments all day, and go home with her on the weekends.

      “As I’m sampling oil, I’m recognizing that nothing I’m doing is going to help women like her escape the illness,” Plata recalls.

      In her third year of the MIT-WHOI program, Plata shifted her research to explore how industrial emissions generated during the creation of materials known as carbon nanotubes could inform how those valuable new materials were forming. The work led to a dramatically more sustainable way to make the materials, which are needed for important environmental applications themselves.

      After earning her PhD, Plata served as a visiting professor at MIT for two years before working in faculty positions at Duke University and Yale University, where she studied green chemistry and green optimization. She returned to MIT as an assistant professor in civil and environmental engineering in 2018.

      Working beyond academia

      While at Yale, Plata started a company, Nth Cycle, which uses electric currents to extract critical minerals like cobalt and nickel from lithium-ion batteries and other electronic waste. The company began commercial production last year.

      Plata also works extensively with government and industry, serving on a Massachusetts committee that published a roadmap to decarbonizing the state by 2050 and advising companies both formally and informally. (She estimates she gets a call every two weeks from a new company working on a sustainability problem.)

      “It’s undeniable that industry has an enormous impact on the environment,” Plata says. “Some like to think the government can wave a magic wand and make some regulation and we won’t be in this situation, but that’s not the case. There are technical challenges that need to be solved and businesses play an incredibly important role as agents of change.”

      Plata’s research at MIT, meanwhile, is focused increasingly on methane. Last year she helped create the MIT Methane Network, which she directs.

      Plata’s research has explored ways to convert methane into less harmful carbon dioxide and other fuels in places like dairy farms and coal plants. This past summer she took a team of students to dairy barns to conduct field tests.

      “If you could take methane from coal mining out of the air globally, it’s equivalent to taking all of the combustion engine vehicles off the road, even accounting for the small generation of CO2 that we have [as the result of our process],” Plata says. “If you can fix the problem at dairy farms, it’s like all the combustion engine vehicle emissions times three. It’s a hugely impactful number.”

      Taking action

      When Plata was in fourth grade, her teacher had students pick up trash around a nearby bay. She’s since done the exercise with other fourth graders.

      “You ask them what they think they’ll find, and they say, ‘Nothing. I didn’t see any trash on the way to school today,’ but when you ask them to look, everybody fills their bag by the end of the trip, and you start to realize how much fugitive emissions of waste exists, and then you start to start thinking about all of the chemical contamination that you can’t see,” Plata says.

      One of Plata’s chief research goals can be summed up with that exercise: getting people to appreciate the importance of environmental criteria and motivating them to take action.

      “Today, I see people looking for these silver bullet solutions to solve environmental problems,” Plata says. “That’s not how we got into this mess, and it’s not how we’re going to get out of it. The problem is really distributed, so what we really need is the sum of a lot of small actions to change the system.” More