More stories

  • in

    Computing our climate future

    On Monday, MIT announced five multiyear flagship projects in the first-ever Climate Grand Challenges, a new initiative to tackle complex climate problems and deliver breakthrough solutions to the world as quickly as possible. This article is the first in a five-part series highlighting the most promising concepts to emerge from the competition, and the interdisciplinary research teams behind them.

    With improvements to computer processing power and an increased understanding of the physical equations governing the Earth’s climate, scientists are continually working to refine climate models and improve their predictive power. But the tools they’re refining were originally conceived decades ago with only scientists in mind. When it comes to developing tangible climate action plans, these models remain inscrutable to the policymakers, public safety officials, civil engineers, and community organizers who need their predictive insight most.

    “What you end up having is a gap between what’s typically used in practice, and the real cutting-edge science,” says Noelle Selin, a professor in the Institute for Data, Systems and Society and the Department of Earth, Atmospheric and Planetary Sciences (EAPS), and co-lead with Professor Raffaele Ferrari on the MIT Climate Grand Challenges flagship project “Bringing Computation to the Climate Crisis.” “How can we use new computational techniques, new understandings, new ways of thinking about modeling, to really bridge that gap between state-of-the-art scientific advances and modeling, and people who are actually needing to use these models?”

    Using this as a driving question, the team won’t just be trying to refine current climate models, they’re building a new one from the ground up.

    This kind of game-changing advancement is exactly what the MIT Climate Grand Challenges is looking for, which is why the proposal has been named one of the five flagship projects in the ambitious Institute-wide program aimed at tackling the climate crisis. The proposal, which was selected from 100 submissions and was among 27 finalists, will receive additional funding and support to further their goal of reimagining the climate modeling system. It also brings together contributors from across the Institute, including the MIT Schwarzman College of Computing, the School of Engineering, and the Sloan School of Management.

    When it comes to pursuing high-impact climate solutions that communities around the world can use, “it’s great to do it at MIT,” says Ferrari, EAPS Cecil and Ida Green Professor of Oceanography. “You’re not going to find many places in the world where you have the cutting-edge climate science, the cutting-edge computer science, and the cutting-edge policy science experts that we need to work together.”

    The climate model of the future

    The proposal builds on work that Ferrari began three years ago as part of a joint project with Caltech, the Naval Postgraduate School, and NASA’s Jet Propulsion Lab. Called the Climate Modeling Alliance (CliMA), the consortium of scientists, engineers, and applied mathematicians is constructing a climate model capable of more accurately projecting future changes in critical variables, such as clouds in the atmosphere and turbulence in the ocean, with uncertainties at least half the size of those in existing models.

    To do this, however, requires a new approach. For one thing, current models are too coarse in resolution — at the 100-to-200-kilometer scale — to resolve small-scale processes like cloud cover, rainfall, and sea ice extent. But also, explains Ferrari, part of this limitation in resolution is due to the fundamental architecture of the models themselves. The languages most global climate models are coded in were first created back in the 1960s and ’70s, largely by scientists for scientists. Since then, advances in computing driven by the corporate world and computer gaming have given rise to dynamic new computer languages, powerful graphics processing units, and machine learning.

    For climate models to take full advantage of these advancements, there’s only one option: starting over with a modern, more flexible language. Written in Julia, a part of Julialab’s Scientific Machine Learning technology, and spearheaded by Alan Edelman, a professor of applied mathematics in MIT’s Department of Mathematics, CliMA will be able to harness far more data than the current models can handle.

    “It’s been real fun finally working with people in computer science here at MIT,” Ferrari says. “Before it was impossible, because traditional climate models are in a language their students can’t even read.”

    The result is what’s being called the “Earth digital twin,” a climate model that can simulate global conditions on a large scale. This on its own is an impressive feat, but the team wants to take this a step further with their proposal.

    “We want to take this large-scale model and create what we call an ‘emulator’ that is only predicting a set of variables of interest, but it’s been trained on the large-scale model,” Ferrari explains. Emulators are not new technology, but what is new is that these emulators, being referred to as the “Earth digital cousins,” will take advantage of machine learning.

    “Now we know how to train a model if we have enough data to train them on,” says Ferrari. Machine learning for projects like this has only become possible in recent years as more observational data become available, along with improved computer processing power. The goal is to create smaller, more localized models by training them using the Earth digital twin. Doing so will save time and money, which is key if the digital cousins are going to be usable for stakeholders, like local governments and private-sector developers.

    Adaptable predictions for average stakeholders

    When it comes to setting climate-informed policy, stakeholders need to understand the probability of an outcome within their own regions — in the same way that you would prepare for a hike differently if there’s a 10 percent chance of rain versus a 90 percent chance. The smaller Earth digital cousin models will be able to do things the larger model can’t do, like simulate local regions in real time and provide a wider range of probabilistic scenarios.

    “Right now, if you wanted to use output from a global climate model, you usually would have to use output that’s designed for general use,” says Selin, who is also the director of the MIT Technology and Policy Program. With the project, the team can take end-user needs into account from the very beginning while also incorporating their feedback and suggestions into the models, helping to “democratize the idea of running these climate models,” as she puts it. Doing so means building an interactive interface that eventually will give users the ability to change input values and run the new simulations in real time. The team hopes that, eventually, the Earth digital cousins could run on something as ubiquitous as a smartphone, although developments like that are currently beyond the scope of the project.

    The next thing the team will work on is building connections with stakeholders. Through participation of other MIT groups, such as the Joint Program on the Science and Policy of Global Change and the Climate and Sustainability Consortium, they hope to work closely with policymakers, public safety officials, and urban planners to give them predictive tools tailored to their needs that can provide actionable outputs important for planning. Faced with rising sea levels, for example, coastal cities could better visualize the threat and make informed decisions about infrastructure development and disaster preparedness; communities in drought-prone regions could develop long-term civil planning with an emphasis on water conservation and wildfire resistance.

    “We want to make the modeling and analysis process faster so people can get more direct and useful feedback for near-term decisions,” she says.

    The final piece of the challenge is to incentivize students now so that they can join the project and make a difference. Ferrari has already had luck garnering student interest after co-teaching a class with Edelman and seeing the enthusiasm students have about computer science and climate solutions.

    “We’re intending in this project to build a climate model of the future,” says Selin. “So it seems really appropriate that we would also train the builders of that climate model.” More

  • in

    New power sources

    In the mid-1990s, a few energy activists in Massachusetts had a vision: What if citizens had choice about the energy they consumed? Instead of being force-fed electricity sources selected by a utility company, what if cities, towns, and groups of individuals could purchase power that was cleaner and cheaper?

    The small group of activists — including a journalist, the head of a small nonprofit, a local county official, and a legislative aide — drafted model legislation along these lines that reached the state Senate in 1995. The measure stalled out. In 1997, they tried again. Massachusetts legislators were busy passing a bill to reform the state power industry in other ways, and this time the activists got their low-profile policy idea included in it — as a provision so marginal it only got a brief mention in The Boston Globe’s coverage of the bill.

    Today, this idea, often known as Community Choice Aggregation (CCA), is used by roughly 36 million people in the U.S., or 11 percent of the population. Local residents, as a bloc, purchase energy with certain specifications attached, and over 1,800 communities have adopted CCA in six states, with others testing CCA pilot programs. From such modest beginnings, CCA has become a big deal.

    “It started small, then had a profound impact,” says David Hsu, an associate professor at MIT who studies energy policy issues. Indeed, the trajectory of CCA is so striking that Hsu has researched its origins, combing through a variety of archival sources and interviewing the principals. He has now written a journal article examining the lessons and implications of this episode.

    Hsu’s paper, “Straight out of Cape Cod: The origin of community choice aggregation and its spread to other states,” appears in advance online form in the journal Energy Research and Social Science, and in the April print edition of the publication.

    “I wanted to show people that a small idea could take off into something big,” Hsu says. “For me that’s a really hopeful democratic story, where people could do something without feeling they had to take on a whole giant system that wouldn’t immediately respond to only one person.”

    Local control

    Aggregating consumers to purchase energy was not a novelty in the 1990s. Companies within many industries have long joined forces to gain purchasing power for energy. And Rhode Island tried a form of CCA slightly earlier than Massachusetts did.

    However, it is the Massachusetts model that has been adopted widely: Cities or towns can require power purchases from, say, renewable sources, while individual citizens can opt out of those agreements. More state funding (for things like efficiency improvements) is redirected to cities and towns as well.

    In both ways, CCA policies provide more local control over energy delivery. They have been adopted in California, Illinois, New Jersey, New York, and Ohio. Meanwhile, Maryland, New Hampshire, and Virginia have recently passed similar legislation (also known as municipal or government aggregation, or community choice energy).

    For cities and towns, Hsu says, “Maybe you don’t own outright the whole energy system, but let’s take away one particular function of the utility, which is procurement.”

    That vision motivated a handful of Massachusetts activists and policy experts in the 1990s, including journalist Scott Ridley, who co-wrote a 1986 book, “Power Struggle,” with the University of Massachusetts historian Richard Rudolph and had spent years thinking about ways to reconfigure the energy system; Matt Patrick, chair of a local nonprofit focused on energy efficiency; Rob O’Leary, a local official in Barnstable County, on Cape Cod; and Paul Fenn, a staff aide to the state senator who chaired the legislature’s energy committee.

    “It started with these political activists,” Hsu says.

    Hsu’s research emphasizes several lessons to be learned from the fact the legislation first failed in 1995, before unexpectedly passing in 1997. Ridley remained an author and public figure; Patrick and O’Leary would each eventually be elected to the state legislature, but only after 2000; and Fenn had left his staff position by 1995 and worked with the group long-distance from California (where he became a long-term advocate about the issue). Thus, at the time CCA passed in 1997, none of its main advocates held an insider position in state politics. How did it succeed?

    Lessons of the legislation

    In the first place, Hsu believes, a legislative process resembles what the political theorist John Kingdon has called a “multiple streams framework,” in which “many elements of the policymaking process are separate, meandering, and uncertain.” Legislation isn’t entirely controlled by big donors or other interest groups, and “policy entrepreneurs” can find success in unpredictable windows of opportunity.

    “It’s the most true-to-life theory,” says Hsu.  

    Second, Hsu emphasizes, finding allies is crucial. In the case of CCA, that came about in a few ways. Many towns in Massachusetts have a town-level legislature known as Town Meeting; the activists got those bodies in about 20 towns to pass nonbinding resolutions in favor of community choice. O’Leary helped create a regional county commission in Barnstable County, while Patrick crafted an energy plan for it. High electricity rates were affecting all of Cape Cod at the time, so community choice also served as an economic benefit for Cape Cod’s working-class service-industry employees. The activists also found that adding an opt-out clause to the 1997 version appealed to legislators, who would support CCA if their constituents were not all bound to it.

    “You really have to stick with it, and you have to look for coalition partners,” Hsu says. “It’s fun to hear them [the activists] talk about going to Town Meetings, and how they tried to build grassroots support. If you look for allies, you can get things done. [I hope] the people can see [themselves] in other people’s activism even if they’re not exactly the same as you are.”

    By 1997, the CCA legislation had more geographic support, was understood as both an economic and environmental benefit for voters, and would not force membership upon anyone. The activists, while giving media interviews, and holding conferences, had found additional traction in the principle of citizen choice.

    “It’s interesting to me how the rhetoric of [citizen] choice and the rhetoric of democracy proves to be effective,” Hsu says. “Legislators feel like they have to give everyone some choice. And it expresses a collective desire for a choice that the utilities take away by being monopolies.”

    He adds: “We need to set out principles that shape systems, rather than just taking the system as a given and trying to justify principles that are 150 years old.”

    One last element in CCA passage was good timing. The governor and legislature in Massachusetts were already seeking a “grand bargain” to restructure electricity delivery and loosen the grip of utilities; the CCA fit in as part of this larger reform movement. Still, CCA adoption has been gradual; about one-third of Massachusetts towns with CCA have only adopted it within the last five years.

    CCA’s growth does not mean it’s invulnerable to repeal or utility-funded opposition efforts — “In California there’s been pretty intense pushback,” Hsu notes. Still, Hsu concludes, the fact that a handful of activists could start a national energy-policy movement is a useful reminder that everyone’s actions can make a difference.

    “It wasn’t like they went charging through a barricade, they just found a way around it,” Hsu says. “I want my students to know you can organize and rethink the future. It takes some commitment and work over a long time.” More

  • in

    Conversations at the front line of climate

    The climate crisis is a novel and developing chapter in human and planetary history. As a species, humankind is still very much learning how to face this crisis, and the world’s frontline communities — those being most affected by climate change — are struggling to make their voices heard. How can communities imperiled by climate change convey the urgency of their situation to countries and organizations with the means to make a difference? And how can governments and other powerful groups provide resources to these vulnerable frontline communities?The MIT Civic Design Initiative (CDI), an interdisciplinary confluence of media studies and design expertise, emerged in 2020 to tackle just these kinds of questions. It brings together the MIT Design Lab, a program originally founded in the School of Architecture and Planning with its research practices in design, and the Comparative Media Studies program (CMS/W) with its focus on the fundamentals of human connection and communication. Drawing on these complementary sources of scholarly perspective and expertise, CDI is a suitably broad umbrella for the range of climate-related issues that humanistic research and design can potentially address. Based in the CMS/W program of the School of Humanities, Arts, and Social Sciences, the initiative is responding to the climate crises with a spirit of inquiry, listening, and solid data. Reflecting on the mission, James Paradis, the Robert M. Metcalfe Professor of CMS/W and CDI faculty director, says the core idea is to address global issues by combining new and emerging technologies with an equally keen focus on the social and cultural contexts — the human dimensions of the issue — with many of their nuances.  Working closely with Paradis on this vision are the two CDI co-directors: Yihyun Lim, an architect, urban designer, and MIT researcher; and Eric Gordon, a visiting professor of civic media in MIT CMS/W. Prior to CDI, when she was leading the MIT Design Lab research group, Lim says “At MIT Design Lab, I was working within the realm of applied research with industry partnerships, how we can apply user-centered design methods in creating connected experiences. Eric, Jim, and I wanted to shift the focus into a more civic realm, where we could bring all our collective expertise together to address tricky problems.”

    Deep listeningThe initiative’s flagship project, the Deep Listening Project, is currently working with an initial group of frontline communities in Nepal and Indigenous tribes in the United States and Canada. The work is a direct application of communication protocols: understanding how people are communicating with and often without technologies — and how technologies can be better used to help people get the help they need, when they need it, in the face of the climate crisis.

    The CDI team describes deep listening as “a form of institutional and community intake that considers diversity, tensions, and frictions, and that incorporates communities’ values in creating solutions.”

    Globally, the majority of climate response funding currently goes toward mitigation efforts — such as reducing emissions or using more eco-friendly materials. It is only in recent years that more substantial funding has been focused on climate adaptation: making adjustments that can help a community adapt to present changes and impacts and also prepare for future climate-related crises. For the millions of people in frontline communities, such adaptation can be crucial to protecting and sustaining their communities.Gordon describes the scope of the situation: “We know that over the next 10 years, climate change will drive over 100 million people to adapt where and how they live, regardless of the success of mitigation efforts. And in order for those adaptations to succeed, there must be a concerted collaborative effort between frontline communities and institutions with the resources to facilitate adaptation.“Communication between institutions and their constituents is a fundamental planning problem in any context,” Gordon continues. “In the case of climate adaptation, there will not be a surplus of time to get things right. Putting communication mechanisms in place to connect affected communities with institutional resources is already imperative.“This situation requires that we figure out, quickly, how to listen to the people who will rely on [those institutions] for their lives and livelihoods. We want to understand how institutions — from governments to universities to NGOs [nongovernmental organizations] — are adopting and adapting technologies, and how that is benefiting or hurting their constituencies.  People with direct frontline experience need to be supported in their speech and ideas, and institutions need to be able to take in the data from these communities, listen carefully to discern its significance, and then act upon it.” Sensemaking: infrastructure for connection

    One important aspect of meaningful, effective communication will be the ability of frontline and Indigenous communities to communicate likely or imagined futures, based on their own knowledge and desires. One potential tool is what the initiative calls “sensemaking:” producing and sharing data visualizations that can communicate to governments the experiences of frontline communities. The initiative also hopes to develop additional elements of the “deep listening infrastructure” — mechanisms to make sure important community voices carry and that important data isn’t lost to noise in the vast question of climate adaptability.“Oftentimes in academia, the paper gets published or the website gets developed, and everybody says, ‘OK, we’ve done our work,’” Paradis observes. “What we’re aiming to do in the CDI is the necessary work that happens after the publication of research — where research is applied to actually improve peoples’ lives.”The Deep Listening Project is also building a network of scholars and practitioners nationwide, including Henry Jenkins, co-founder and former faculty member at MIT CMS/W; Sangita Shresthova SM ’03 at the University of Southern California; and Darren Ranco at the University of Maine. Ranco, an anthropologist, Indigenous activist, and organizational leader, has been instrumental in connecting with Indigenous groups and tribal governments across North America. Meanwhile, Gordon has helped forge connections with groups like the International Red Cross/Red Crescent, the World Bank, and the UN Development. At the root of these connections is the impetus to communicate lived realities from the level of a small community to that of global relief organizations and governmental powers.

    Potential human futures

    Mona Vijaykumar, a second-year student in the SMArchS Architecture and Urbanism program in the Department of Architecture, and among the first student researcher assistants attached to the new initiative, is excited to have the chance to help build CDI from the ground up. “It’s been a great honor to be working with CDI’s amazing team for the last eight months,” she says. With her background in urban design and research interest in climate adaptation processes, Vijaykumar has been engaged in developing the Deep Listening Project’s white paper as part of MIT Climate Grand Challenges. She works alongside the initiative’s two other inaugural research assistants: Tomas Guarna, a master’s student in CMS, and Gabriela Degetau, a master’s student in the SMarchS Urbanism program, with Vijaykumar.“I was involved in analyzing the literature case study on community-based adaptation processes and co-writing the white paper,” Vijaykumar says, “and am currently working on conducting interviews with communities and institutions in India. Going forward, Gabriela and I will be presenting the white paper at gatherings such as the American Association of Geographers’ Conference in New York and the Climate and Social Impact Conference in Vancouver.”“The support and collaboration of the team have been incredibly empowering,” reflects Degetau, who will be co-presenting the white paper with Vijaykumar in New York and Vancouver, British Columbia. “Even when working from different countries and through Zoom, the experience has been unique and cohesive.”Both Degetau and Vijaykumar were selected as the first fellows of the Vuslat Foundation, organized by the MIT Transmedia Storytelling Initiative. In this one-year fellowship, they are seeking to co-design “climate imaginaries” through the Deep Listening Project. Vijaykumar’s work is also supported by the MIT Human Rights and Technology Fellowship for 2021-22, which guides her personal focus on what she refers to as the “dual sword” of technology and data colonialism in India.As the Deep Listening Project continues to develop a sustainable and balanced communication infrastructure, Lim reflects that a vital part of that is sharing how potential futures are envisioned. Both large institutions and individual communities imagine, separately — and hopefully soon together — how the human world will reshape itself to be viable in profoundly shifting climate conditions. “What are our possible futures?” asks Lim. “What are people dreaming?” 

    Story prepared by MIT SHASS CommunicationsEditorial and design director: Emily HiestandSenior communications associate: Alison Lanier More

  • in

    J-PAL North America announces five new partnerships with state and local governments

    J-PAL North America, a research center in MIT’s Department of Economics, has announced five new partnerships with state and local governments across the United States after a call for proposals in early February. Over the next year, these partners will work with J-PAL North America’s State and Local Innovation Initiative to evaluate policy-relevant questions critical to alleviating poverty in the United States.

    J-PAL North America will work with the Colorado Department of Higher Education, Ohio’s Franklin County Department of Job and Family Services, the New Mexico Public Education Department, Puerto Rico’s Department of Economic Development and Commerce, and Oregon’s Jackson County Fire District 3. Each partner will leverage support from J-PAL North America to develop randomized evaluations, which have the potential to reveal widely applicable lessons about which programs and policies are most effective. 

    State and local leaders are vital stakeholders in developing rigorous evidence in order to understand which policies and programs work to reduce poverty, and why. By supporting each government partner in developing these five evaluation projects, the voice of policymakers and practitioners will remain a central part of the research process. Each of this year’s selected projects seeks to address policy concerns that have been identified by state and local governments in J-PAL North America’s State and Local Learning Agenda as key areas for addressing barriers to mobility from poverty, including environment, education, economic security, and housing stability. 

    One project looks to mitigate the emission of carbon co-pollutants, which cause disproportionately high rates of health problems among communities experiencing poverty. 

    Oregon’s Jackson County Fire District 3 will investigate the impact of subsidies on the uptake of wildfire risk reduction activities in a county severely affected by wildfires. “Wildfires have become more prevalent, longer lasting, and more destructive in Oregon and across the western United States. We also know that wildfire is disproportionately impacting our most vulnerable populations,” says Bob Horton, fire chief of Jackson County Fire District 3. “With technical support from JPAL North America’s staff and this grant funding, we will devise the most current and effective strategy, deeply rooted in the evidence, to drive the take-up of home-hardening behaviors — methods to increase a home’s resistance to fire — and lower the risk to homes when faced with wildfire.” 

    This project is in alignment with the priorities of J-PAL’s Environment, Energy, and Climate Change sector and its agenda for catalyzing more policy-relevant research on adaptation strategies. 

    Policymakers and researchers have also identified programs aimed at increasing opportunity within education as a key priority for evaluation. In partnering with J-PAL North America, the Colorado Department of Higher Education will assess the impact of My Colorado Journey, an online platform available to all Coloradans that provides information on education, training, and career pathways. 

    “As Colorado builds back stronger from the pandemic, we know that education and workforce development are at the center of Colorado’s recovery agenda,” shares Executive Director Angie Paccione of the Colorado Department of Education. “Platforms like My Colorado Journey are key to supporting the education, training, and workforce exploration of Coloradans of any age. With support from J-PAL North America, we can better understand how to effectively serve Coloradans, further enhance this vital platform, and continue to build a Colorado for all.”

    Similarly, the New Mexico Public Education Department proposes their intervention within the context of New Mexico’s community school state initiative. They will look at the impact of case management and cash transfers on students at risk of multiple school transfers throughout their education, which include children who are experiencing homelessness, migrant children, children in the foster care system, and military-connected children, among others. “New Mexico is delighted to partner with J-PAL North America to explore visionary pathways to success for highly mobile students,” says New Mexico Public Education Secretary (Designate) Kurt Steinhaus. “We look forward to implementing and testing innovative solutions, such as cash transfers, that can expand our current nationally recognized community schools strategy. Together, we aim to find solutions that meet the needs of highly mobile students and families who lack stable housing.”

    Another key priority for the intersection of policy and research is economic security — fostering upward mobility by providing individuals with resources to promote stable incomes and increase standards of living. By adjusting caseworker employment services to better align with local needs, Puerto Rico’s Department of Economic Development and Commerce (DEDC) looks to understand how individualized services can impact employment and earnings. 

    “The commitment of the government of Puerto Rico is to develop human resources to the highest quality standards,” says DEDC Secretary Cidre Miranda, whose statement was provided in Spanish and translated. “For the DEDC, it is fundamental to contribute to the development of initiatives like this one, because they have the objective of forging the future professionals that Puerto Rico requires and needs.” J-PAL North America’s partnership with DEDC has the potential to provide valuable lessons for other state and local programs also seeking to promote economic security. 

    Finally, Ohio’s Franklin County Department of Job and Family Services seeks to understand the impact of an eviction prevention workshop in a county with eviction rates that are higher than both the state and national average. “Stable housing should not be a luxury, but for far too many Franklin County families it has become one,” Deputy Franklin County Administrator Joy Bivens says. “We need to view our community’s affordable housing crisis through both a social determinants of health and racial equity lens. We are grateful for the opportunity to partner with J-PAL North America to ensure we are pursuing research-based interventions that, yes, address immediate housing needs, but also provide long-term stability so they can climb the economic ladder.”

    Franklin County Department of Job and Family Services’ evaluation aligns with policymaker and researcher interests to ensure safe and affordable housing. This partnership will have great potential to not only improve resources local to Franklin County, but, along with each of the other four agencies, can also provide a useful model for other government agencies facing similar challenges.For more information on state and local policy priorities, see J-PAL North America’s State and Local Learning Agenda. To learn more about the State and Local Innovation Initiative, please visit the Initiative webpage or contact Initiative Manager Louise Geraghty. More

  • in

    Q&A: Can the world change course on climate?

    In this ongoing series on climate issues, MIT faculty, students, and alumni in the humanistic fields share perspectives that are significant for solving climate change and mitigating its myriad social and ecological impacts. Nazli Choucri is a professor of political science and an expert on climate issues, who also focuses on international relations and cyberpolitics. She is the architect and director of the Global System for Sustainable Development, an evolving knowledge networking system centered on sustainability problems and solution strategies. The author and/or editor of 12 books, she is also the founding editor of the MIT Press book series “Global Environmental Accord: Strategies for Sustainability and Institutional Innovation.” Q: The impacts of climate change — including storms, floods, wildfires, and droughts — have the potential to destabilize nations, yet they are not constrained by borders. What international developments most concern you in terms of addressing climate change and its myriad ecological and social impacts?

    A: Climate change is a global issue. By definition, and a long history of practice, countries focus on their own priorities and challenges. Over time, we have seen the gradual development of norms reflecting shared interests, and the institutional arrangements to support and pursue the global good. What concerns me most is that general responses to the climate crisis are being framed in broad terms; the overall pace of change remains perilously slow; and uncertainty remains about operational action and implementation of stated intent. We have just seen the completion of the 26th meeting of states devoted to climate change, the United Nations Climate Change Conference (COP26). In some ways this is positive. Yet, past commitments remain unfulfilled, creating added stress in an already stressful political situation. Industrial countries are uneven in their recognition of, and responses to, climate change. This may signal uncertainty about whether climate matters are sufficiently compelling to call for immediate action. Alternatively, the push for changing course may seem too costly at a time when other imperatives — such as employment, economic growth, or protecting borders — inevitably dominate discourse and decisions. Whatever the cause, the result has been an unwillingness to take strong action. Unfortunately, climate change remains within the domain of “low politics,” although there are signs the issue is making a slow but steady shift to “high politics” — those issues deemed vital to the existence of the state. This means that short-term priorities, such as those noted above, continue to shape national politics and international positions and, by extension, to obscure the existential threat revealed by scientific evidence. As for developing countries, these are overwhelmed by internal challenges, and managing the difficulties of daily life always takes priority over other challenges, however compelling. Long-term thinking is a luxury, but daily bread is a necessity. Non-state actors — including registered nongovernmental organizations, climate organizations, sustainability support groups, activists of various sorts, and in some cases much of civil society — have been left with a large share of the responsibility for educating and convincing diverse constituencies of the consequences of inaction on climate change. But many of these institutions carry their own burdens and struggle to manage current pressures. The international community, through its formal and informal institutions, continues to articulate the perils of climate change and to search for a powerful consensus that can prove effective both in form and in function. The general contours are agreed upon — more or less. But leadership of, for, and by the global collective is elusive and difficult to shape. Most concerning of all is the clear reluctance to address head-on the challenge of planning for changes that we know will occur. The reality that we are all being affected — in different ways and to different degrees — has yet to be sufficiently appreciated by everyone, everywhere. Yet, in many parts of the world, major shifts in climate will create pressures on human settlements, spur forced migrations, or generate social dislocations. Some small island states, for example, may not survive a sea-level surge. Everywhere there is a need to cut emissions, and this means adaptation and/or major changes in economic activity and in lifestyle.The discourse and debate at COP26 reflect all of such persistent features in the international system. So far, the largest achievements center on the common consensus that more must be done to prevent the rise in temperature from creating a global catastrophe. This is not enough, however. Differences remain, and countries have yet to specify what cuts in emissions they are willing to make.Echoes of who is responsible for what remains strong. The thorny matter of the unfulfilled pledge of $100 billion once promised by rich countries to help countries to reduce their emissions remained unresolved. At the same time, however, some important agreements were reached. The United States and China announced they would make greater efforts to cut methane, a powerful greenhouse gas. More than 100 countries agreed to end deforestation. India joined the countries committed to attain zero emissions by 2070. And on matters of finance, countries agreed to a two-year plan to determine how to meet the needs of the most-vulnerable countries. Q: In what ways do you think the tools and insights from political science can advance efforts to address climate change and its impacts?A: I prefer to take a multidisciplinary view of the issues at hand, rather than focus on the tools of political science alone. Disciplinary perspectives can create siloed views and positions that undermine any overall drive toward consensus. The scientific evidence is pointing to, even anticipating, pervasive changes that transcend known and established parameters of social order all across the globe.That said, political science provides important insight, even guidance, for addressing the impacts of climate change in some notable ways. One is understanding the extent to which our formal institutions enable discussion, debate, and decisions about the directions we can take collectively to adapt, adjust, or even depart from the established practices of managing social order.If we consider politics as the allocation of values in terms of who gets what, when, and how, then it becomes clear that the current allocation requires a change in course. Coordination and cooperation across the jurisdictions of sovereign states is foundational for any response to climate change impacts.We have already recognized, and to some extent, developed targets for reducing carbon emissions — a central impact from traditional forms of energy use — and are making notable efforts to shift toward alternatives. This move is an easy one compared to all the work that needs to be done to address climate change. But, in taking this step we have learned quite a bit that might help in creating a necessary consensus for cross-jurisdiction coordination and response.Respecting individuals and protecting life is increasingly recognized as a global value — at least in principle. As we work to change course, new norms will be developed, and political science provides important perspectives on how to establish such norms. We will be faced with demands for institutional design, and these will need to embody our guiding values. For example, having learned to recognize the burdens of inequity, we can establish the value of equity as foundational for our social order both now and as we recognize and address the impacts of climate change.

    Q: You teach a class on “Sustainability Development: Theory and Practice.” Broadly speaking, what are goals of this class? What lessons do you hope students will carry with them into the future?A: The goal of 17.181, my class on sustainability, is to frame as clearly as possible the concept of sustainable development (sustainability) with attention to conceptual, empirical, institutional, and policy issues.The course centers on human activities. Individuals are embedded in complex interactive systems: the social system, the natural environment, and the constructed cyber domain — each with distinct temporal, special, and dynamic features. Sustainability issues intersect with, but cannot be folded into, the impacts of climate change. Sustainability places human beings in social systems at the core of what must be done to respect the imperatives of a highly complex natural environment.We consider sustainability an evolving knowledge domain with attendant policy implications. It is driven by events on the ground, not by revolution in academic or theoretical concerns per se. Overall, sustainable development refers to the process of meeting the needs of current and future generations, without undermining the resilience of the life-supporting properties, the integrity of social systems, or the supports of the human-constructed cyberspace.More specifically, we differentiate among four fundamental dimensions and their necessary conditions:

    (a) ecological systems — exhibiting balance and resilience;(b) economic production and consumption — with equity and efficiency;(c) governance and politics — with participation and responsiveness; and(d) institutional performance — demonstrating adaptation and incorporating feedback.The core proposition is this: If all conditions hold, then the system is (or can be) sustainable. Then, we must examine the critical drivers — people, resources, technology, and their interactions — followed by a review and assessment of evolving policy responses. Then we ask: What are new opportunities?I would like students to carry forward these ideas and issues: what has been deemed “normal” in modern Western societies and in developing societies seeking to emulate the Western model is damaging humans in many ways — all well-known. Yet only recently have alternatives begun to be considered to the traditional economic growth model based on industrialization and high levels of energy use. To make changes, we must first understand the underlying incentives, realities, and choices that shape a whole set of dysfunctional behaviors and outcomes. We then need to delve deep into the driving sources and consequences, and to consider the many ways in which our known “normal” can be adjusted — in theory and in practice. Q: In confronting an issue as formidable as global climate change, what gives you hope?  A: I see a few hopeful signs; among them:The scientific evidence is clear and compelling. We are no longer discussing whether there is climate change, or if we will face major challenges of unprecedented proportions, or even how to bring about an international consensus on the salience of such threats.Climate change has been recognized as a global phenomenon. Imperatives for cooperation are necessary. No one can go it alone. Major efforts have and are being made in world politics to forge action agendas with specific targets.The issue appears to be on the verge of becoming one of “high politics” in the United States.Younger generations are more sensitive to the reality that we are altering the life-supporting properties of our planet. They are generally more educated, skilled, and open to addressing such challenges than their elders.However disappointing the results of COP26 might seem, the global community is moving in the right direction.None of the above points, individually or jointly, translates into an effective response to the known impacts of climate change — let alone the unknown. But, this is what gives me hope.

    Interview prepared by MIT SHASS CommunicationsEditorial, design, and series director: Emily HiestandSenior writer: Kathryn O’Neill More

  • in

    At UN climate change conference, trying to “keep 1.5 alive”

    After a one-year delay caused by the Covid-19 pandemic, negotiators from nearly 200 countries met this month in Glasgow, Scotland, at COP26, the United Nations climate change conference, to hammer out a new global agreement to reduce greenhouse gas emissions and prepare for climate impacts. A delegation of approximately 20 faculty, staff, and students from MIT was on hand to observe the negotiations, share and conduct research, and launch new initiatives.

    On Saturday, Nov. 13, following two weeks of negotiations in the cavernous Scottish Events Campus, countries’ representatives agreed to the Glasgow Climate Pact. The pact reaffirms the goal of the 2015 Paris Agreement “to pursue efforts” to limit the global average temperature increase to 1.5 degrees Celsius above preindustrial levels, and recognizes that achieving this goal requires “reducing global carbon dioxide emissions by 45 percent by 2030 relative to the 2010 level and to net zero around mid-century.”

    “On issues like the need to reach net-zero emissions, reduce methane pollution, move beyond coal power, and tighten carbon accounting rules, the Glasgow pact represents some meaningful progress, but we still have so much work to do,” says Maria Zuber, MIT’s vice president for research, who led the Institute’s delegation to COP26. “Glasgow showed, once again, what a wicked complex problem climate change is, technically, economically, and politically. But it also underscored the determination of a global community of people committed to addressing it.”

    An “ambition gap”

    Both within the conference venue and at protests that spilled through the streets of Glasgow, one rallying cry was “keep 1.5 alive.” Alok Sharma, who was appointed by the UK government to preside over COP26, said in announcing the Glasgow pact: “We can now say with credibility that we have kept 1.5 degrees alive. But, its pulse is weak and it will only survive if we keep our promises and translate commitments into rapid action.”

    In remarks delivered during the first week of the conference, Sergey Paltsev, deputy director of MIT’s Joint Program on the Science and Policy of Global Change, presented findings from the latest MIT Global Change Outlook, which showed a wide gap between countries’ nationally determined contributions (NDCs) — the UN’s term for greenhouse gas emissions reduction pledges — and the reductions needed to put the world on track to meet the goals of the Paris Agreement and, now, the Glasgow pact.

    Pointing to this ambition gap, Paltsev called on all countries to do more, faster, to cut emissions. “We could dramatically reduce overall climate risk through more ambitious policy measures and investments,” says Paltsev. “We need to employ an integrated approach of moving to zero emissions in energy and industry, together with sustainable development and nature-based solutions, simultaneously improving human well-being and providing biodiversity benefits.”

    Finalizing the Paris rulebook

    A key outcome of COP26 (COP stands for “conference of the parties” to the UN Framework Convention on Climate Change, held for the 26th time) was the development of a set of rules to implement Article 6 of the Paris Agreement, which provides a mechanism for countries to receive credit for emissions reductions that they finance outside their borders, and to cooperate by buying and selling emissions reductions on international carbon markets.

    An agreement on this part of the Paris “rulebook” had eluded negotiators in the years since the Paris climate conference, in part because negotiators were concerned about how to prevent double-counting, wherein both buyers and sellers would claim credit for the emissions reductions.

    Michael Mehling, the deputy director of MIT’s Center for Energy and Environmental Policy Research (CEEPR) and an expert on international carbon markets, drew on a recent CEEPR working paper to describe critical negotiation issues under Article 6 during an event at the conference on Nov. 10 with climate negotiators and private sector representatives.

    He cited research that finds that Article 6, by leveraging the cost-efficiency of global carbon markets, could cut in half the cost that countries would incur to achieve their nationally determined contributions. “Which, seen from another angle, means you could double the ambition of these NDCs at no additional cost,” Mehling noted in his talk, adding that, given the persistent ambition gap, “any such opportunity is bitterly needed.”

    Andreas Haupt, a graduate student in the Institute for Data, Systems, and Society, joined MIT’s COP26 delegation to follow Article 6 negotiations. Haupt described the final days of negotiations over Article 6 as a “roller coaster.” Once negotiators reached an agreement, he says, “I felt relieved, but also unsure how strong of an effect the new rules, with all their weaknesses, will have. I am curious and hopeful regarding what will happen in the next year until the next large-scale negotiations in 2022.”

    Nature-based climate solutions

    World leaders also announced new agreements on the sidelines of the formal UN negotiations. One such agreement, a declaration on forests signed by more than 100 countries, commits to “working collectively to halt and reverse forest loss and land degradation by 2030.”

    A team from MIT’s Environmental Solutions Initiative (ESI), which has been working with policymakers and other stakeholders on strategies to protect tropical forests and advance other nature-based climate solutions in Latin America, was at COP26 to discuss their work and make plans for expanding it.

    Marcela Angel, a research associate at ESI, moderated a panel discussion featuring John Fernández, professor of architecture and ESI’s director, focused on protecting and enhancing natural carbon sinks, particularly tropical forests such as the Amazon that are at risk of deforestation, forest degradation, and biodiversity loss.

    “Deforestation and associated land use change remain one of the main sources of greenhouse gas emissions in most Amazonian countries, such as Brazil, Peru, and Colombia,” says Angel. “Our aim is to support these countries, whose nationally determined contributions depend on the effectiveness of policies to prevent deforestation and promote conservation, with an approach based on the integration of targeted technology breakthroughs, deep community engagement, and innovative bioeconomic opportunities for local communities that depend on forests for their livelihoods.”

    Energy access and renewable energy

    Worldwide, an estimated 800 million people lack access to electricity, and billions more have only limited or erratic electrical service. Providing universal access to energy is one of the UN’s sustainable development goals, creating a dual challenge: how to boost energy access without driving up greenhouse gas emissions.

    Rob Stoner, deputy director for science and technology of the MIT Energy Initiative (MITEI), and Ignacio Pérez-Arriaga, a visiting professor at the Sloan School of Management, attended COP26 to share their work as members of the Global Commission to End Energy Poverty, a collaboration between MITEI and the Rockefeller Foundation. It brings together global energy leaders from industry, the development finance community, academia, and civil society to identify ways to overcome barriers to investment in the energy sectors of countries with low energy access.

    The commission’s work helped to motivate the formation, announced at COP26 on Nov. 2, of the Global Energy Alliance for People and Planet, a multibillion-dollar commitment by the Rockefeller and IKEA foundations and Bezos Earth Fund to support access to renewable energy around the world.

    Another MITEI member of the COP26 delegation, Martha Broad, the initiative’s executive director, spoke about MIT research to inform the U.S. goal of scaling offshore wind energy capacity from approximately 30 megawatts today to 30 gigawatts by 2030, including significant new capacity off the coast of New England.

    Broad described research, funded by MITEI member companies, on a coating that can be applied to the blades of wind turbines to prevent icing that would require the turbines’ shutdown; the use of machine learning to inform preventative turbine maintenance; and methodologies for incorporating the effects of climate change into projections of future wind conditions to guide wind farm siting decisions today. She also spoke broadly about the need for public and private support to scale promising innovations.

    “Clearly, both the public sector and the private sector have a role to play in getting these technologies to the point where we can use them in New England, and also where we can deploy them affordably for the developing world,” Broad said at an event sponsored by America Is All In, a coalition of nonprofit and business organizations.

    Food and climate alliance

    Food systems around the world are increasingly at risk from the impacts of climate change. At the same time, these systems, which include all activities from food production to consumption and food waste, are responsible for about one-third of the human-caused greenhouse gas emissions warming the planet.

    At COP26, MIT’s Abdul Latif Jameel Water and Food Systems Lab announced the launch of a new alliance to drive research-based innovation that will make food systems more resilient and sustainable, called the Food and Climate Systems Transformation (FACT) Alliance. With 16 member institutions, the FACT Alliance will better connect researchers to farmers, food businesses, policymakers, and other food systems stakeholders around the world.

    Looking ahead

    By the end of 2022, the Glasgow pact asks countries to revisit their nationally determined contributions and strengthen them to bring them in line with the temperature goals of the Paris Agreement. The pact also “notes with deep regret” the failure of wealthier countries to collectively provide poorer countries $100 billion per year in climate financing that they pledged in 2009 to begin in 2020.

    These and other issues will be on the agenda for COP27, to be held in Sharm El-Sheikh, Egypt, next year.

    “Limiting warming to 1.5 degrees is broadly accepted as a critical goal to avoiding worsening climate consequences, but it’s clear that current national commitments will not get us there,” says ESI’s Fernández. “We will need stronger emissions reductions pledges, especially from the largest greenhouse gas emitters. At the same time, expanding creativity, innovation, and determination from every sector of society, including research universities, to get on with real-world solutions is essential. At Glasgow, MIT was front and center in energy systems, cities, nature-based solutions, and more. The year 2030 is right around the corner so we can’t afford to let up for one minute.” More

  • in

    Q&A: Options for the Diablo Canyon nuclear plant

    The Diablo Canyon nuclear plant in California, the only one still operating in the state, is set to close in 2025. A team of researchers at MIT’s Center for Advanced Nuclear Energy Systems, Abdul Latif Jameel Water and Food Systems Lab, and Center for Energy and Environmental Policy Research; Stanford’s Precourt Energy Institute; and energy analysis firm LucidCatalyst LLC have analyzed the potential benefits the plant could provide if its operation were extended to 2030 or 2045.

    They found that this nuclear plant could simultaneously help to stabilize the state’s electric grid, provide desalinated water to supplement the state’s chronic water shortages, and provide carbon-free hydrogen fuel for transportation. MIT News asked report co-authors Jacopo Buongiorno, the TEPCO Professor of Nuclear Science and Engineering, and John Lienhard, the Jameel Professor of Water and Food, to discuss the group’s findings.

    Q: Your report suggests co-locating a major desalination plant alongside the existing Diablo Canyon power plant. What would be the potential benefits from operating a desalination plant in conjunction with the power plant?

    Lienhard: The cost of desalinated water produced at Diablo Canyon would be lower than for a stand-alone plant because the cost of electricity would be significantly lower and you could take advantage of the existing infrastructure for the intake of seawater and the outfall of brine. Electricity would be cheaper because the location takes advantage of Diablo Canyon’s unique capability to provide low cost, zero-carbon baseload power.

    Depending on the scale at which the desalination plant is built, you could make a very significant impact on the water shortfalls of state and federal projects in the area. In fact, one of the numbers that came out of this study was that an intermediate-sized desalination plant there would produce more fresh water than the highest estimate of the net yield from the proposed Delta Conveyance Project on the Sacramento River. You could get that amount of water at Diablo Canyon for an investment cost less than half as large, and without the associated impacts that would come with the Delta Conveyance Project.

    And the technology envisioned for desalination here, reverse osmosis, is available off the shelf. You can buy this equipment today. In fact, it’s already in use in California and thousands of other places around the world.

    Q: You discuss in the report three potential products from the Diablo Canyon plant:  desalinatinated water, power for the grid, and clean hydrogen. How well can the plant accommodate all of those efforts, and are there advantages to combining them as opposed to doing any one of them separately?

    Buongiorno: California, like many other regions in the world, is facing multiple challenges as it seeks to reduce carbon emissions on a grand scale. First, the wide deployment of intermittent energy sources such as solar and wind creates a great deal of variability on the grid that can be balanced by dispatchable firm power generators like Diablo. So, the first mission for Diablo is to continue to provide reliable, clean electricity to the grid.

    The second challenge is the prolonged drought and water scarcity for the state in general. And one way to address that is water desalination co-located with the nuclear plant at the Diablo site, as John explained.

    The third challenge is related to decarbonization the transportation sector. A possible approach is replacing conventional cars and trucks with vehicles powered by fuel cells which consume hydrogen. Hydrogen has to be produced from a primary energy source. Nuclear power, through a process called electrolysis, can do that quite efficiently and in a manner that is carbon-free.

    Our economic analysis took into account the expected revenue from selling these multiple products — electricity for the grid, hydrogen for the transportation sector, water for farmers or other local users — as well as the costs associated with deploying the new facilities needed to produce desalinated water and hydrogen. We found that, if Diablo’s operating license was extended until 2035, it would cut carbon emissions by an average of 7 million metric tons a year — a more than 11 percent reduction from 2017 levels — and save ratepayers $2.6 billion in power system costs.

    Further delaying the retirement of Diablo to 2045 would spare 90,000 acres of land that would need to be dedicated to renewable energy production to replace the facility’s capacity, and it would save ratepayers up to $21 billion in power system costs.

    Finally, if Diablo was operated as a polygeneration facility that provides electricity, desalinated water, and hydrogen simultaneously, its value, quantified in terms of dollars per unit electricity generated, could increase by 50 percent.

    Lienhard: Most of the desalination scenarios that we considered did not consume the full electrical output of that plant, meaning that under most scenarios you would continue to make electricity and do something with it, beyond just desalination. I think it’s also important to remember that this power plant produces 15 percent of California’s carbon-free electricity today and is responsible for 8 percent of the state’s total electrical production. In other words, Diablo Canyon is a very large factor in California’s decarbonization. When or if this plant goes offline, the near-term outcome is likely to be increased reliance on natural gas to produce electricity, meaning a rise in California’s carbon emissions.

    Q: This plant in particular has been highly controversial since its inception. What’s your assessment of the plant’s safety beyond its scheduled shutdown, and how do you see this report as contributing to the decision-making about that shutdown?

    Buongiorno: The Diablo Canyon Nuclear Power Plant has a very strong safety record. The potential safety concern for Diablo is related to its proximity to several fault lines. Being located in California, the plant was designed to withstand large earthquakes to begin with. Following the Fukushima accident in 2011, the Nuclear Regulatory Commission reviewed the plant’s ability to withstand external events (e.g., earthquakes, tsunamis, floods, tornadoes, wildfires, hurricanes) of exceptionally rare and severe magnitude. After nine years of assessment the NRC’s conclusion is that “existing seismic capacity or effective flood protection [at Diablo Canyon] will address the unbounded reevaluated hazards.” That is, Diablo was designed and built to withstand even the rarest and strongest earthquakes that are physically possible at this site.

    As an additional level of protection, the plant has been retrofitted with special equipment and procedures meant to ensure reliable cooling of the reactor core and spent fuel pool under a hypothetical scenario in which all design-basis safety systems have been disabled by a severe external event.

    Lienhard: As for the potential impact of this report, PG&E [the California utility] has already made the decision to shut down the plant, and we and others hope that decision will be revisited and reversed. We believe that this report gives the relevant stakeholders and policymakers a lot of information about options and value associated with keeping the plant running, and about how California could benefit from clean water and clean power generated at Diablo Canyon. It’s not up to us to make the decision, of course — that is a decision that must be made by the people of California. All we can do is provide information.

    Q: What are the biggest challenges or obstacles to seeing these ideas implemented?

    Lienhard: California has very strict environmental protection regulations, and it’s good that they do. One of the areas of great concern to California is the health of the ocean and protection of the coastal ecosystem. As a result, very strict rules are in place about the intake and outfall of both power plants and desalination plants, to protect marine life. Our analysis suggests that this combined plant can be implemented within the parameters prescribed by the California Ocean Plan and that it can meet the regulatory requirements.

    We believe that deeper analysis would be needed before you could proceed. You would need to do site studies and really get out into the water and look in detail at what’s there. But the preliminary analysis is positive. A second challenge is that the discourse in California around nuclear power has generally not been very supportive, and similarly some groups in California oppose desalination. We expect that that both of those points of view would be part of the conversation about whether or not to procede with this project.

    Q: How particular is this analysis to the specifics of this location? Are there aspects of it that apply to other nuclear plants, domestically or globally?

    Lienhard: Hundreds of nuclear plants around the world are situated along the coast, and many are in water stressed regions. Although our analysis focused on Diablo Canyon, we believe that the general findings are applicable to many other seaside nuclear plants, so that this approach and these conclusions could potentially be applied at hundreds of sites worldwide. More

  • in

    Making roadway spending more sustainable

    The share of federal spending on infrastructure has reached an all-time low, falling from 30 percent in 1960 to just 12 percent in 2018.

    While the nation’s ailing infrastructure will require more funding to reach its full potential, recent MIT research finds that more sustainable and higher performing roads are still possible even with today’s limited budgets.

    The research, conducted by a team of current and former MIT Concrete Sustainability Hub (MIT CSHub) scientists and published in Transportation Research D, finds that a set of innovative planning strategies could improve pavement network environmental and performance outcomes even if budgets don’t increase.

    The paper presents a novel budget allocation tool and pairs it with three innovative strategies for managing pavement networks: a mix of paving materials, a mix of short- and long-term paving actions, and a long evaluation period for those actions.

    This novel approach offers numerous benefits. When applied to a 30-year case study of the Iowa U.S. Route network, the MIT CSHub model and management strategies cut emissions by 20 percent while sustaining current levels of road quality. Achieving this with a conventional planning approach would require the state to spend 32 percent more than it does today. The key to its success is the consideration of a fundamental — but fraught — aspect of pavement asset management: uncertainty.

    Predicting unpredictability

    The average road must last many years and support the traffic of thousands — if not millions — of vehicles. Over that time, a lot can change. Material prices may fluctuate, budgets may tighten, and traffic levels may intensify. Climate (and climate change), too, can hasten unexpected repairs.

    Managing these uncertainties effectively means looking long into the future and anticipating possible changes.

    “Capturing the impacts of uncertainty is essential for making effective paving decisions,” explains Fengdi Guo, the paper’s lead author and a departing CSHub research assistant.

    “Yet, measuring and relating these uncertainties to outcomes is also computationally intensive and expensive. Consequently, many DOTs [departments of transportation] are forced to simplify their analysis to plan maintenance — often resulting in suboptimal spending and outcomes.”

    To give DOTs accessible tools to factor uncertainties into their planning, CSHub researchers have developed a streamlined planning approach. It offers greater specificity and is paired with several new pavement management strategies.

    The planning approach, known as Probabilistic Treatment Path Dependence (PTPD), is based on machine learning and was devised by Guo.

    “Our PTPD model is composed of four steps,” he explains. “These steps are, in order, pavement damage prediction; treatment cost prediction; budget allocation; and pavement network condition evaluation.”

    The model begins by investigating every segment in an entire pavement network and predicting future possibilities for pavement deterioration, cost, and traffic.

    “We [then] run thousands of simulations for each segment in the network to determine the likely cost and performance outcomes for each initial and subsequent sequence, or ‘path,’ of treatment actions,” says Guo. “The treatment paths with the best cost and performance outcomes are selected for each segment, and then across the network.”

    The PTPD model not only seeks to minimize costs to agencies but also to users — in this case, drivers. These user costs can come primarily in the form of excess fuel consumption due to poor road quality.

    “One improvement in our analysis is the incorporation of electric vehicle uptake into our cost and environmental impact predictions,” Randolph Kirchain, a principal research scientist at MIT CSHub and MIT Materials Research Laboratory (MRL) and one of the paper’s co-authors. “Since the vehicle fleet will change over the next several decades due to electric vehicle adoption, we made sure to consider how these changes might impact our predictions of excess energy consumption.”

    After developing the PTPD model, Guo wanted to see how the efficacy of various pavement management strategies might differ. To do this, he developed a sophisticated deterioration prediction model.

    A novel aspect of this deterioration model is its treatment of multiple deterioration metrics simultaneously. Using a multi-output neural network, a tool of artificial intelligence, the model can predict several forms of pavement deterioration simultaneously, thereby, accounting for their correlations among one another.

    The MIT team selected two key metrics to compare the effectiveness of various treatment paths: pavement quality and greenhouse gas emissions. These metrics were then calculated for all pavement segments in the Iowa network.

    Improvement through variation

     The MIT model can help DOTs make better decisions, but that decision-making is ultimately constrained by the potential options considered.

    Guo and his colleagues, therefore, sought to expand current decision-making paradigms by exploring a broad set of network management strategies and evaluating them with their PTPD approach. Based on that evaluation, the team discovered that networks had the best outcomes when the management strategy includes using a mix of paving materials, a variety of long- and short-term paving repair actions (treatments), and longer time periods on which to base paving decisions.

    They then compared this proposed approach with a baseline management approach that reflects current, widespread practices: the use of solely asphalt materials, short-term treatments, and a five-year period for evaluating the outcomes of paving actions.

    With these two approaches established, the team used them to plan 30 years of maintenance across the Iowa U.S. Route network. They then measured the subsequent road quality and emissions.

    Their case study found that the MIT approach offered substantial benefits. Pavement-related greenhouse gas emissions would fall by around 20 percent across the network over the whole period. Pavement performance improved as well. To achieve the same level of road quality as the MIT approach, the baseline approach would need a 32 percent greater budget.

    “It’s worth noting,” says Guo, “that since conventional practices employ less effective allocation tools, the difference between them and the CSHub approach should be even larger in practice.”

    Much of the improvement derived from the precision of the CSHub planning model. But the three treatment strategies also play a key role.

    “We’ve found that a mix of asphalt and concrete paving materials allows DOTs to not only find materials best-suited to certain projects, but also mitigates the risk of material price volatility over time,” says Kirchain.

    It’s a similar story with a mix of paving actions. Employing a mix of short- and long-term fixes gives DOTs the flexibility to choose the right action for the right project.

    The final strategy, a long-term evaluation period, enables DOTs to see the entire scope of their choices. If the ramifications of a decision are predicted over only five years, many long-term implications won’t be considered. Expanding the window for planning, then, can introduce beneficial, long-term options.

    It’s not surprising that paving decisions are daunting to make; their impacts on the environment, driver safety, and budget levels are long-lasting. But rather than simplify this fraught process, the CSHub method aims to reflect its complexity. The result is an approach that provides DOTs with the tools to do more with less.

    This research was supported through the MIT Concrete Sustainability Hub by the Portland Cement Association and the Ready Mixed Concrete Research and Education Foundation. More