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      in Environment

      Climate and sustainability classes expand at MIT

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      In fall 2019, a new class, 6.S898/12.S992 (Climate Change Seminar), arrived at MIT. It was, at the time, the only course in the Department of Electrical Engineering and Computer Science (EECS) to tackle the science of climate change. The class covered climate models and simulations alongside atmospheric science, policy, and economics.

      Ron Rivest, MIT Institute Professor of Computer Science, was one of the class’s three instructors, with Alan Edelman of the Computer Science and Artificial Intelligence Laboratory (CSAIL) and John Fernández of the Department of Urban Studies and Planning. “Computer scientists have much to contribute to climate science,” Rivest says. “In particular, the modeling and simulation of climate can benefit from advances in computer science.”

      Rivest is one of many MIT faculty members who have been working in recent years to bring topics in climate, sustainability, and the environment to students in a growing variety of fields. And students have said they want this trend to continue.

      “Sustainability is something that touches all disciplines,” says Megan Xu, a rising senior in biological engineering and advisory chair of the Undergraduate Association Sustainability Committee. “As students who have grown up knowing that climate change is real and witnessed climate disaster after disaster, we know this is a huge problem that needs to be addressed by our generation.”

      Expanding the course catalog

      As education program manager at the MIT Environmental Solutions Initiative, Sarah Meyers has repeatedly had a hand in launching new sustainability classes. She has steered grant money to faculty, brought together instructors, and helped design syllabi — all in the service of giving MIT students the same world-class education in climate and sustainability that they get in science and engineering.

      Her work has given Meyers a bird’s-eye view of MIT’s course offerings in this area. By her count, there are now over 120 undergraduate classes, across 23 academic departments, that teach climate, environment, and sustainability principles.

      “Educating the next generation is the most important way that MIT can have an impact on the world’s environmental challenges,” she says. “MIT students are going to be leaders in their fields, whatever they may be. If they really understand sustainable design practices, if they can balance the needs of all stakeholders to make ethical decisions, then that actually changes the way our world operates and can move humanity towards a more sustainable future.”

      Some sustainability classes are established institutions at MIT. Success stories include 2.00A (Fundamentals of Engineering Design: Explore Space, Sea and Earth), a hands-on engineering class popular with first-year students; and 21W.775 (Writing About Nature and Environmental Issues), which has helped undergraduates fulfill their HASS-H (humanities distribution subject) and CI-H (Communication Intensive subject in the Humanities, Arts, and Social Sciences) graduation requirements for 15 years.

      Expanding this list of classes is an institutional priority. In the recently released Climate Action Plan for the Decade, MIT pledged to recruit at least 20 additional faculty members who will teach climate-related classes.

      “I think it’s easy to find classes if you’re looking for sustainability classes to take,” says Naomi Lutz, a senior in mechanical engineering who helped advise the MIT administration on education measures in the Climate Action Plan. “I usually scroll through the titles of the classes in courses 1, 2, 11, and 12 to see if any are of interest. I also have used the Environment & Sustainability Minor class list to look for sustainability-related classes to take.

      “The coming years are critical for the future of our planet, so it’s important that we all learn about sustainability and think about how to address it,” she adds.

      Working with students’ schedules

      Still, despite all this activity, climate and sustainability are not yet mainstream parts of an MIT education. Last year, a survey of over 800 MIT undergraduates, taken by the Undergraduate Association Sustainability Committee, found that only one in four had ever taken a class related to sustainability. But it doesn’t seem to be from lack of interest in the topic. More than half of those surveyed said that sustainability is a factor in their career planning, and almost 80 percent try to practice sustainability in their daily lives.

      “I’ve often had conversations with students who were surprised to learn there are so many classes available,” says Meyers. “We do need to do a better job communicating about them, and making it as easy as possible to enroll.”

      A recurring challenge is helping students fit sustainability into their plans for graduation, which are often tightly mapped-out.

      “We each only have four years — around 32 to 40 classes — to absorb all that we can from this amazing place,” says Xu. “Many of these classes are mandated to be GIRs [General Institute Requirements] and major requirements. Many students recognize that sustainability is important, but might not have the time to devote an entire class to the topic if it would not count toward their requirements.”

      This was a central focus for the students who were involved in forming education recommendations for the Climate Action Plan. “We propose that more sustainability-related courses or tracks are offered in the most common majors, especially in Course 6 [EECS],” says Lutz. “If students can fulfill major requirements while taking courses that address environmental problems, we believe more students will pursue research and careers related to sustainability.”

      She also recommends that students look into the dozens of climate and sustainability classes that fulfill GIRs. “It’s really easy to take sustainability-related courses that fulfill HASS [Humanities, Arts, and Social Sciences] requirements,” she says. For example, students can meet their HASS-S (social sciences sistribution subject) requirement by taking 21H.185 (Environment and History), or fulfill their HASS-A requirement with CMS.374 (Transmedia Art, Extraction and Environmental Justice).

      Classes with impact

      For those students who do seek out sustainability classes early in their MIT careers, the experience can shape their whole education.

      “My first semester at MIT, I took Environment and History, co-taught by professors Susan Solomon and Harriet Ritvo,” says Xu. “It taught me that there is so much more involved than just science and hard facts to solving problems in sustainability and climate. I learned to look at problems with more of a focus on people, which has informed much of the extracurricular work that I’ve gone on to do at MIT.”

      And the faculty, too, sometimes find that teaching in this area opens new doors for them. Rivest, who taught the climate change seminar in Course 6, is now working to build a simplified climate model with his co-instructor Alan Edelman, their teaching assistant Henri Drake, and Professor John Deutch of the Department of Chemistry, who joined the class as a guest lecturer. “I very much enjoyed meeting new colleagues from all around MIT,” Rivest says. “Teaching a class like this fosters connections between computer scientists and climate scientists.”

      Which is why Meyers will continue helping to get these classes off the ground. “We know students think climate is a huge issue for their futures. We know faculty agree with them,” she says. “Everybody wants this to be part of an MIT education. The next step is to really reach out to students and departments to fill the classrooms. That’s the start of a virtuous cycle where enrollment drives more sustainability instruction in every part of MIT.” More

    • 88 Shares99 Views

      in Environment

      A new approach to preventing human-induced earthquakes

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      When humans pump large volumes of fluid into the ground, they can set off potentially damaging earthquakes, depending on the underlying geology. This has been the case in certain oil- and gas-producing regions, where wastewater, often mixed with oil, is disposed of by injecting it back into the ground — a process that has triggered sizable seismic events in recent years.

      Now MIT researchers, working with an interdisciplinary team of scientists from industry and academia, have developed a method to manage such human-induced seismicity, and have demonstrated that the technique successfully reduced the number of earthquakes occurring in an active oil field.

      Their results, appearing today in Nature, could help mitigate earthquakes caused by the oil and gas industry, not just from the injection of wastewater produced with oil, but also that produced from hydraulic fracturing, or “fracking.” The team’s approach could also help prevent quakes from other human activities, such as the filling of water reservoirs and aquifers, and the sequestration of carbon dioxide in deep geologic formations.

      “Triggered seismicity is a problem that goes way beyond producing oil,” says study lead author Bradford Hager, the Cecil and Ida Green Professor of Earth Sciences in MIT’s Department of Earth, Atmospheric and Planetary Sciences. “This is a huge problem for society that will have to be confronted if we are to safely inject carbon dioxide into the subsurface. We demonstrated the kind of study that will be necessary for doing this.”

      The study’s co-authors include Ruben Juanes, professor of civil and environmental engineering at MIT, and collaborators from the University of California at Riverside, the University of Texas at Austin, Harvard University, and Eni, a multinational oil and gas company based in Italy.

      Safe injections

      Both natural and human-induced earthquakes occur along geologic faults, or fractures between two blocks of rock in the Earth’s crust. In stable periods, the rocks on either side of a fault are held in place by the pressures generated by surrounding rocks. But when a large volume of fluid is suddenly injected at high rates, it can upset a fault’s fluid stress balance. In some cases, this sudden injection can lubricate a fault and cause rocks on either side to slip and trigger an earthquake.

      The most common source of such fluid injections is from the oil and gas industry’s disposal of wastewater that is brought up along with oil. Field operators dispose of this water through injection wells that continuously pump the water back into the ground at high pressures.

      “There’s a lot of water produced with the oil, and that water is injected into the ground, which has caused a large number of quakes,” Hager notes. “So, for a while, oil-producing regions in Oklahoma had more magnitude 3 quakes than California, because of all this wastewater that was being injected.”

      In recent years, a similar problem arose in southern Italy, where injection wells on oil fields operated by Eni triggered microseisms in an area where large naturally occurring earthquakes had previously occurred. The company, looking for ways to address the problem, sought consulation from Hager and Juanes, both leading experts in seismicity and subsurface flows.

      “This was an opportunity for us to get access to high-quality seismic data about the subsurface, and learn how to do these injections safely,” Juanes says.

      Seismic blueprint

      The team made use of detailed information, accumulated by the oil company over years of operation in the Val D’Agri oil field, a region of southern Italy that lies in a tectonically active basin. The data included information about the region’s earthquake record, dating back to the 1600s, as well as the structure of rocks and faults, and the state of the subsurface corresponding to the various injection rates of each well.

      This video shows the change in stress on the geologic faults of the Val d’Agri field from 2001 to 2019, as predicted by a new MIT-derived model. Video credit: A. Plesch (Harvard University)

      This video shows small earthquakes occurring on the Costa Molina fault within the Val d’Agri field from 2004 to 2016. Each event is shown for two years fading from an initial bright color to the final dark color. Video credit: A. Plesch (Harvard University)

      The researchers integrated these data into a coupled subsurface flow and geomechanical model, which predicts how the stresses and strains of underground structures evolve as the volume of pore fluid, such as from the injection of water, changes. They connected this model to an earthquake mechanics model in order to translate the changes in underground stress and fluid pressure into a likelihood of triggering earthquakes. They then quantified the rate of earthquakes associated with various rates of water injection, and identified scenarios that were unlikely to trigger large quakes.

      When they ran the models using data from 1993 through 2016, the predictions of seismic activity matched with the earthquake record during this period, validating their approach. They then ran the models forward in time, through the year 2025, to predict the region’s seismic response to three different injection rates: 2,000, 2,500, and 3,000 cubic meters per day. The simulations showed that large earthquakes could be avoided if operators kept injection rates at 2,000 cubic meters per day — a flow rate comparable to a small public fire hydrant.

      Eni field operators implemented the team’s recommended rate at the oil field’s single water injection well over a 30-month period between January 2017 and June 2019. In this time, the team observed only a few tiny seismic events, which coincided with brief periods when operators went above the recommended injection rate.

      “The seismicity in the region has been very low in these two-and-a-half years, with around four quakes of 0.5 magnitude, as opposed to hundreds of quakes, of up to 3 magnitude, that were happening between 2006 and 2016,” Hager says. 

      The results demonstrate that operators can successfully manage earthquakes by adjusting injection rates, based on the underlying geology. Juanes says the team’s modeling approach may help to prevent earthquakes related to other processes, such as the building of water reservoirs and the sequestration of carbon dioxide — as long as there is detailed information about a region’s subsurface.

      “A lot of effort needs to go into understanding the geologic setting,” says Juanes, who notes that, if carbon sequestration were carried out on depleted oil fields, “such reservoirs could have this type of history, seismic information, and geologic interpretation that you could use to build similar models for carbon sequestration. We show it’s at least possible to manage seismicity in an operational setting. And we offer a blueprint for how to do it.”

      This research was supported, in part, by Eni. More