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Thursday, October 11th, 2018
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| 12:00a |
Self-healing material can build itself from carbon in the air A material designed by MIT chemical engineers can react with carbon dioxide from the air, to grow, strengthen, and even repair itself. The polymer, which might someday be used as construction or repair material or for protective coatings, continuously converts the greenhouse gas into a carbon-based material that reinforces itself.
The current version of the new material is a synthetic gel-like substance that performs a chemical process similar to the way plants incorporate carbon dioxide from the air into their growing tissues. The material might, for example, be made into panels of a lightweight matrix that could be shipped to a construction site, where they would harden and solidify just from exposure to air and sunlight, thereby saving on the energy and cost of transportation.
The finding is described in a paper in the journal Advanced Materials, by Professor Michael Strano, postdoc Seon-Yeong Kwak, and eight others at MIT and at the University of California at Riverside
“This is a completely new concept in materials science,” says Strano, the Carbon C. Dubbs Professor of Chemical Engineering. “What we call carbon-fixing materials don’t exist yet today” outside of the biological realm, he says, describing materials that can transform carbon dioxide in the ambient air into a solid, stable form, using only the power of sunlight, just as plants do.
Developing a synthetic material that not only avoids the use of fossil fuels for its creation, but actually consumes carbon dioxide from the air, has obvious benefits for the environment and climate, the researchers point out. “Imagine a synthetic material that could grow like trees, taking the carbon from the carbon dioxide and incorporating it into the material’s backbone,” Strano says.
The material the team used in these initial proof-of-concept experiments did make use of one biological component — chloroplasts, the light-harnessing components within plant cells, which the researchers obtained from spinach leaves. The chloroplasts are not alive but catalyze the reaction of carbon dioxide to glucose. Isolated chloroplasts are quite unstable, meaning that they tend to stop functioning after a few hours when removed from the plant. In their paper, Strano and his co-workers demonstrate methods to significantly increase the catalytic lifetime of extracted chloroplasts. In ongoing and future work, the chloroplast is being replaced by catalysts that are nonbiological in origin, Strano explains.
The material the researchers used, a gel matrix composed of a polymer made from aminopropyl methacrylamide (APMA) and glucose, an enzyme called glucose oxidase, and the chloroplasts, becomes stronger as it incorporates the carbon. It is not yet strong enough to be used as a building material, though it might function as a crack filling or coating material, the researchers say.
The team has worked out methods to produce materials of this type by the ton, and is now focusing on optimizing the material’s properties. Commercial applications such as self-healing coatings and crack filling are realizable in the near term, they say, whereas additional advances in backbone chemistry and materials science are needed before construction materials and composites can be developed.
One key advantage of such materials is they would be self-repairing upon exposure to sunlight or some indoor lighting, Strano says. If the surface is scratched or cracked, the affected area grows to fill in the gaps and repair the damage, without requiring any external action.
While there has been widespread effort to develop self-healing materials that could mimic this ability of biological organisms, the researchers say, these have all required an active outside input to function. Heating, UV light, mechanical stress, or chemical treatment were needed to activate the process. By contrast, these materials need nothing but ambient light, and they incorporate mass from carbon in the atmosphere, which is ubiquitous.
The material starts out as a liquid, Kwak says, adding, “it is exciting to watch it as it starts to grow and cluster” into a solid form.
“Materials science has never produced anything like this,” Strano says. “These materials mimic some aspects of something living, even though it’s not reproducing.” Because the finding opens up a wide array of possible follow-up research, the U.S. Department of Energy is sponsoring a new program directed by Strano to develop it further.
“Our work shows that carbon dioxide need not be purely a burden and a cost,” Strano says. “It is also an opportunity in this respect. There’s carbon everywhere. We build the world with carbon. Humans are made of carbon. Making a material that can access the abundant carbon all around us is a significant opportunity for materials science. In this way, our work is about making materials that are not just carbon neutral, but carbon negative.”
The research team included Juan Pablo Giraldo at UC Riverside, and Tedrick Lew, Min Hao Wong, Pingwei Liu, Yun Jung Yang, Volodomyr Koman, Melissa McGee and Bradley Olsen at MIT. The work was supported by the U.S. Department of Energy. | | 9:00a |
Powered by idealism and pragmatism When they first met as graduate students in 2012, Samuel Shaner SM ’14, PhD ’18 and Mathew Ellis PhD ’17 realized they shared a common passion.
“Sam was one year ahead of me, and as my official buddy during orientation weekend, he took me to the MIT Energy Conference,” recalls Ellis. “That first night, we began sharing ideas about what we wanted to see happen in the nuclear industry.”
Adds Shaner: “We were both really interested in the innovative side of the industry and doing something entrepreneurial with nuclear reactor development.”
The connection sparked at the start of their acquaintance is now generating dividends. In June, Yellowstone Energy, the company launched by the duo in 2016, received $2.6 million from the Department of Energy's Advanced Research Projects Agency-Energy (ARPA-E). This was one of just 10 awards distributed by a new ARPA-E program, Modeling-Enhanced Innovations Trailblazing Nuclear Energy Reinvigoration (MEITNER), which is intended to identify and develop novel technologies to advance safer and more cost-efficient nuclear reactors.
“It was one of our best days, a really big moment for us,” says Ellis. “After working hard on the enabling technology, winning the grant through a selective and rigorous process was a great accomplishment.”
Shaner says it was incredibly gratifying to receive “such significant validation of the idea we had come up with.”
This idea, the culmination of several years of independent research by Shaner and Ellis, is a design for an advanced, modular nuclear reactor integrating a suite of commonsense but forward-thinking features. Yellowstone Energy’s reactor uses conventional, commercially available uranium dioxide fuel (UO2); operates at near-ambient pressure; and deploys a molten nitrate salt coolant that allows the reactor to reach higher operating temperatures than current water-cooled nuclear reactors. At the heart of this design lies a novel control device that is now under patent review, and in the first stages of testing at Oak Ridge National Laboratory.
Shared frustration to shared vision
Yellowstone Energy and its innovative approach was born out of “frustration with the policy, regulatory, and supply chain challenges of bringing new technologies to market,” says Shaner. “Just to make a small tweak, such as feeding more highly-enriched fuel to current reactors, involves tens of millions of dollars and many years,” he says.
“Sam and I are a good mix of dreamers and pragmatists,” says Ellis. “We realized that a lot of advanced reactor concepts faced hurdles to get to market that went beyond nuclear physics, so we started thinking about how to fix that problem.”
The pair set out to identify a set of reactor properties that would leapfrog the hurdles.
“We needed to have a reactor design and technology that would be inexpensive to build and operate, and given the risks in building new reactors, a design that would promise a time- and capital-efficient pathway to market,” says Shaner.
“We figured that the more we leveraged proven technology, the easier it would be to license the reactor,” says Ellis.
Their first decision was to use what Shaner calls “off-the-shelf” fuel: UO2, the industry standard. But to increase operating efficiency with this fuel, they would need heat transfer fluids different from those circulating in current generation reactors. Other advanced reactor designs suggested fluoride and chloride salts, but these fluids prove technically challenging to engineer for reliable, commercial-scale systems. That led to another major design decision: to deploy molten nitrate salts, a high-temperature, ambient-pressure heat transfer fluid already in widespread use in the chemical and concentrated solar power industries.
The challenge then came in bringing together the current fuel and the molten nitrate salt coolant, says Shaner. As graduate students working in Nuclear Science and Engineering with professors Ben Forget and Kord Smith, Ellis and Shaner had developed expertise in analyzing, modeling, and computing the physics of reactor systems. In a matter of months, they had devised a novel control device that would potentially enable their UO2 and molten-nitrate-salt-based reactor to function.
A leg up for entrepreneurs
In the fall of 2016, the team applied for and received a $25,000 grant from the MIT Sandbox Innovation Fund. With this money, they applied for intellctual property protection on their core enabling technology. But they also received valuable non-financial assistance.
“MIT is one of the few places where big, ambitious ideas like a nuclear reactor startup are encouraged,” says Ellis. “The entrepreneurial ecosystem at MIT, specifically the mentoring through Sandbox, was a big inflection point for us, allowing us to get off the ground, move on with our idea, and ultimately make it a business.”
Today, the team is based in Knoxville, Tennessee, working under the auspices of a Department of Energy incubator, and preparing a first round of simulations at the Oak Ridge Laboratory, with the help of nuclear industry and utility partners. Their collaboration has weathered well.
“Sam and I are very aligned with what we want to do, and the impact we want to make, but we’re always willing to challenge each other to improve our ideas,” says Ellis. “We learned each other's abilities, strengths and quirks during five years together at MIT, which allows us to work really efficiently.”
They've faced their share of challenges. “The hardest part has been the uncertainty, which can make things a roller coaster of emotions,” says Shaner. “For instance, when we finished grad school, we didn't know if we would get funding to continue working on our idea.”
With the endorsement and financial backing of the Department of Energy, they are taking a moment to savor their accomplishment. But they never lose sight of the path before them.
“Nuclear has a longer time horizon than most technologies, so we really have to believe in our mission — clean energy and reducing CO2 emissions — in order to get to the finish line,” says Ellis. “If we’re here a decade from now, it will be because people recognize our approach is fundamentally different, that our technology successfully reduced a lot of the risks, and that we can make a major impact in the near term on energy markets.” | | 9:50a |
3 Questions: Frances Ross on witnessing nanostructure formation Professor Frances Ross joined the MIT Department of Materials Science and Engineering this fall after a career of developing techniques that probe materials reactions while they take place. Formerly with the IBM Thomas J. Watson Research Center in Yorktown Heights, New York, Ross brings to MIT her expertise in applying transmission electron microscopy to understand how nanostructures form in real time and using the data from such movies to develop new structures and growth pathways. She addressed the MIT Materials Research Laboratory Materials Day Symposium “Materials Research at the Nanoscale” on Oct. 10.
Q: What insights do we gain from observing nanoscale crystal structures forming in real-time that were missed when observation was limited to analyzing structures only after their formation?
A: Recording a movie of something growing, rather than images before and after growth, has many exciting advantages. The movie gives us a continuous view of a process, which shows the full evolution. This can include detailed information like the growth rate of an individual nanocrystal. Recording a continuous view makes it easier to catch a rapid nucleation event or a really short-lived intermediate shape, which may often be quite unexpected. The movie also gives us a window into the behavior of materials under real processing conditions, avoiding the changes that usually occur when you stop growth to get ready for post-growth analysis. And finally, it is possible to grow a single object then measure its properties, such as the electrical conductivity of one nanowire or the melting point of a nanocrystal. Of course obtaining such information involves greater experimental complexity, but the results make this extra effort worthwhile, and we really enjoy designing and carrying out these experiments.
Q: What will your role be in moving these techniques forward through the new MIT.nano facility?
A: MIT.nano has some very quiet rooms downstairs. The rooms are designed to have a stable temperature and minimize vibrations and electromagnetic fields from the surroundings, including the nearby T line [subway]. Our plan is to use one of these rooms for a unique new electron microscope. It will be designed for growth experiments that involve two-dimensional materials: not just the famous graphene but others as well. We plan to study growth reactions where “conventional” (three-dimensional) nanocrystals grow on two-dimensional materials — a necessary step in making full use of the interesting new opportunities offered by two-dimensional materials. Growth reactions involving two-dimensional materials are difficult to study using our existing equipment because the materials are damaged by the electrons used for imaging. The new microscope will use lower voltage electrons and will have a high vacuum for precise control of the environment and capabilities for carrying out growth and other processes using reactive gases. This microscope will benefit growth studies in many other materials as well. But not every experiment requires such state-of-the-art equipment, and we also plan to develop new capabilities, particularly for looking at reactions in liquids, in the microscopes that are already operating in Building 13.
Q: What technologies will most immediately benefit through enhanced observation of nanoscale structure formation?
A: I think that any new way of looking at a material or a process tends to impact a much broader area than you at first imagine. It has been very exciting to see how many areas have made use of the opportunities presented by these types of growth experiment. Growth processes in liquids have already probed catalysts in action, biomineralization, fluid physics (such as nanoscale bubbles), corrosion, and materials for rechargeable batteries. Some biological, geological, or atmospheric processes will also eventually benefit from this type of microscopy. Growth reactions involving gases are particularly well suited to addressing questions in catalysis (again), thin films and coatings, processing for microelectronics, structures used in solid-state lighting, and a variety of other technology areas. Our approach has been to choose relatively simple materials that have useful applications — silicon, germanium, copper — but then use the experiments to probe the basic physics underlying the materials’ reaction and see how that might teach us how to build more complex structures. The simpler and more general the model is that explains our observations, the happier we are. | | 2:00p |
Researchers quickly harvest 2-D materials, bringing them closer to commercialization Since the 2003 discovery of the single-atom-thick carbon material known as graphene, there has been significant interest in other types of 2-D materials as well.
These materials could be stacked together like Lego bricks to form a range of devices with different functions, including operating as semiconductors. In this way, they could be used to create ultra-thin, flexible, transparent and wearable electronic devices.
However, separating a bulk crystal material into 2-D flakes for use in electronics has proven difficult to do on a commercial scale.
The existing process, in which individual flakes are split off from the bulk crystals by repeatedly stamping the crystals onto an adhesive tape, is unreliable and time-consuming, requiring many hours to harvest enough material and form a device.
Now researchers in the Department of Mechanical Engineering at MIT have developed a technique to harvest 2-inch diameter wafers of 2-D material within just a few minutes. They can then be stacked together to form an electronic device within an hour.
The technique, which they describe in a paper published in the journal Science, could open up the possibility of commercializing electronic devices based on a variety of 2-D materials, according to Jeehwan Kim, an associate professor in the Department of Mechanical Engineering, who led the research.
The paper’s co-first authors were Sanghoon Bae, who was involved in flexible device fabrication, and Jaewoo Shim, who worked on the stacking of the 2-D material monolayers. Both are postdocs in Kim’s group.
The paper’s co-authors also included students and postdocs from within Kim’s group, as well as collaborators at Georgia Tech, the University of Texas, Yonsei University in South Korea, and the University of Virginia. Sang-Hoon Bae, Jaewoo Shim, Wei Kong, and Doyoon Lee in Kim’s research group equally contributed to this work.
“We have shown that we can do monolayer-by-monolayer isolation of 2-D materials at the wafer scale,” Kim says. “Secondly, we have demonstrated a way to easily stack up these wafer-scale monolayers of 2-D material.”
The researchers first grew a thick stack of 2-D material on top of a sapphire wafer. They then applied a 600-nanometer-thick nickel film to the top of the stack.
Since 2-D materials adhere much more strongly to nickel than to sapphire, lifting off this film allowed the researchers to separate the entire stack from the wafer.
What’s more, the adhesion between the nickel and the individual layers of 2-D material is also greater than that between each of the layers themselves.
As a result, when a second nickel film was then added to the bottom of the stack, the researchers were able to peel off individual, single-atom thick monolayers of 2-D material.
That is because peeling off the first nickel film generates cracks in the material that propagate right through to the bottom of the stack, Kim says.
Once the first monolayer collected by the nickel film has been transferred to a substrate, the process can be repeated for each layer.
“We use very simple mechanics, and by using this controlled crack propagation concept we are able to isolate monolayer 2-D material at the wafer scale,” he says.
The universal technique can be used with a range of different 2-D materials, including hexagonal boron nitride, tungsten disulfide, and molybdenum disulfide.
In this way it can be used to produce different types of monolayer 2-D materials, such as semiconductors, metals, and insulators, which can then be stacked together to form the 2-D heterostructures needed for an electronic device.
“If you fabricate electronic and photonic devices using 2-D materials, the devices will be just a few monolayers thick,” Kim says. “They will be extremely flexible, and can be stamped on to anything,” he says.
The process is fast and low-cost, making it suitable for commercial operations, he adds.
The researchers have also demonstrated the technique by successfully fabricating arrays of field-effect transistors at the wafer scale, with a thickness of just a few atoms.
“The work has a lot of potential to bring 2-D materials and their heterostructures towards real-world applications,” says Philip Kim, a professor of physics at Harvard University, who was not involved in the research.
The researchers are now planning to apply the technique to develop a range of electronic devices, including a nonvolatile memory array and flexible devices that can be worn on the skin.
They are also interested in applying the technique to develop devices for use in the “internet of things,” Kim says.
“All you need to do is grow these thick 2-D materials, then isolate them in monolayers and stack them up. So it is extremely cheap — much cheaper than the existing semiconductor process. This means it will bring laboratory-level 2-D materials into manufacturing for commercialization,” Kim says.
“That makes it perfect for IoT networks, because if you were to use conventional semiconductors for the sensing systems it would be expensive.” | | 2:30p |
Progress against pancreatic cancer Genetically complex and hard to detect in its early stages, pancreatic cancer is the fourth leading cause of cancer mortality in the U.S. It is also a long-standing staple of the MIT cancer research portfolio, with multiple active projects at the Koch Institute and beyond seeking to transform the way the disease is studied and treated.
On Sept. 21, the Lustgarten Foundation, the nation’s largest private funder of pancreatic cancer research, honored MIT’s commitment to pancreatic cancer research with the naming of the Lustgarten Laboratory for Pancreatic Cancer Research at MIT. The Lustgarten Laboratory is headed by Tyler Jacks, director of the Koch Institute and the David H. Koch Professor of Biology.
The Lustgarten Foundation’s investment will support postdocs, graduate students, technicians and a senior scientist for its duration. The Lustgarten Lab’s goals are to better understand the immunological conditions and genetic events that contribute to the development of pancreatic cancer, to study the disease on a single-cell level in both humans and mouse models, and to develop novel high throughput tools for culture and drug testing using mini-organs known as organoids.
The Jacks lab is ideally suited for this massive undertaking, thanks to its solid portfolio of pancreatic cancer research, developed with the support of the Lustgarten Foundation and others, and its deep connections with both biology and engineering laboratories at the Koch Institute and across the MIT campus.
At the dedication ceremony, David Tuveson, the chief scientist of the Lustgarten Foundation, praised the Jacks lab’s “collective skills and talents” and its “highly collaborative approach” as the driving force behind many advances in pancreatic cancer research over the last two decades, a legacy of which Tuveson is part.
Of mice and mentorship
Jacks is widely considered a pioneer in the development of engineered mouse models of human cancers. It was in his laboratory, then a part of MIT’s Center for Cancer Research, the predecessor to the Koch Institute, that Tuveson began work on what would become the KPC mouse model of pancreatic ductal adenocarcinoma (PDAC). The model, which centers around the exploitation of commonly mutated genes Kras (a cancer driver) and p53 (a tumor suppressor) is now the gold standard for pre-clinical studies of the disease. With it, scientists can trace the development of tumors inside a living pancreas from a single mutated cell to metastatic invasion of distant organs.
In a way, the model presents a microcosm of the robust training environment within the Jacks Lab. Current postdoctoral researcher and designated Lustgarten Lab lead scientist Will Freed-Pastor praises his mentor’s willingness to step back and give his mentees space to make their own marks on the world. “Training future leaders,” he says, “is one of Tyler’s most valuable contributions to the field.”
With the new resources from Lustgarten, Jacks looks forward to bringing even more researchers into field and applying knowledge gained from his lab’s work in lung cancer, immunology, and gene editing to the unique challenges of pancreatic tumors.
“We have a formidable team and it is only going to get stronger,” Jacks says. “We are grateful for the Lustgarten Foundation’s investment in our work as it allows us to recruit new investigators from across MIT who have never worked in pancreatic cancer before but whose tools and approaches will help us develop new treatment paradigms for early diagnosis and intervention.”
A signature investment
The naming of the Lustgarten Laboratory for Pancreatic Cancer Research at MIT is happening side-by-side with that of Brian Wolpin’s lab across the river at Dana-Farber Cancer Institute. In addition to serving as the Jacks lab’s clinical liaison, Wolpin has collaborated on pancreatic cancer research with Matthew Vander Heiden, professor of biology and associate director of the Koch Institute.
The dual investment represents a milestone for the Lustgarten Foundation — the second and third lab spaces dedicated to pancreatic cancer research — in its 20th anniversary year. Tuveson heads the first, Cold Spring Harbor Laboratory, where he is now a professor and the director of the Cancer Center.
“We are so excited to usher in a new era of pancreatic cancer research,” says Kerri Kaplan, president and chief executive officer of the Lustgarten Foundation. “Twenty years ago, this was truly an ‘orphan’ disease, but thanks to the commitment and innovative approaches of these researchers at MIT and beyond, we are rapidly expanding our knowledge and ability to improve patient outcomes.”
As a researcher himself and the shepherd of MIT’s transition from the Center for Cancer Research to the Koch Institute, Jacks has long sought to balance basic science research with clinical applications. Pancreatic cancer was among the first disease areas identified as a priority for the Bridge Project, the Koch Institute’s signature collaboration between MIT and Dana-Farber/Harvard Cancer Center. The Lustgarten Foundation was among the primary supporters of the Bridge Project in its inaugural year. Even with these resources, however, pancreatic cancer continues to be a difficult disease to approach.
Jacks and his colleagues describe the Lustgarten investment as high-risk, high-reward — an innovation fund to move beyond incremental improvements at both the bench and the bedside.
“This gives us the freedom to ask very challenging questions about cancer cells themselves and the immune system,” Freed-Pastor says.
Jacks agrees. “This is exactly the right time for this work,” he says. “We understand so much more about this disease than we did two decades ago, and we now have the teams and technologies to transform that knowledge into actionable solutions for patients. We are honored by the Lustgarten Foundation’s trust in that endeavor.” | | 2:45p |
Charting the Earth’s future for the 21st century In 2015 the Paris Agreement specified the need for its nearly 200 signatory nations to implement greenhouse gas emissions reduction policies consistent with keeping the increase in the global average temperature since preindustrial times to well below 2 degrees Celsius — and pursue efforts to further limit that increase to 1.5 C.
Recognizing that the initial, near-term Paris pledges, known as Nationally Determined Contributions (NDCs), are inadequate by themselves to put the globe on track to achieve those goals and thus avoid the worst consequences of climate change, the agreement calls for participating nations to strengthen their NDCs over time. Toward that end, the Intergovernmental Panel on Climate Change (IPCC) released a special report on Oct. 8 on pathways to achieving the 1.5 C goal, and the next Conference of the Parties (COP24) to the United Nations Framework Convention on Climate Change (UNFCCC) convenes in December.
In line with these developments, the MIT Joint Program on the Science and Policy of Global Change has released its 2018 Food, Water, Energy and Climate Outlook. Based on a rigorous, integrated analysis of population and economic growth, technological change, Paris Agreement NDCs, and other factors, the MIT report projects likely global and regional environmental changes over the course of this century and identifies steps needed to align near-term Paris pledges with the long-term 2 C and 1.5 C goals.
This year’s Outlook extends the program’s analysis of Paris Agreement pledges to include commitments of most of the countries of the world, uses a newly updated version of the Joint Program’s Integrated Global System Modeling (IGSM) framework, and relies on updated gross national product (GDP) projections. Projections of the Outlook, which assume that all NDCs (generally including commitments only through 2025 or 2030) are met and retained throughout the century, map out the future of energy and land use; water and agriculture; and emissions and climate. The Outlook concludes with expert perspectives on the progress of key countries and regions in fulfilling their short-term Paris pledges, and potential pathways to meeting the long-term Paris goals.
Future of energy, water and food
Between 2015 and 2050, population and economic growth are projected to lead to further increases in primary energy of about 33 percent, growth in the global vehicle stock by nearly 61 percent, further electrification of the economy, and, with continued land productivity improvement, relatively modest changes in land use.
While successful achievement of Paris Agreement pledges should accelerate a shift away from fossil fuels (from 84 percent in 2015 to 78 percent of primary energy use by 2050) and temper potential rises in fossil fuel prices, it is likely to contribute to increasing global average electricity prices (rising to about 31 percent above 2015 levels by 2050).
Water and agriculture are key sectors that will be shaped not only by increasing demands from population and economic growth but also by the changing global environment. Climate change is likely to add to water stress and reduce agricultural productivity, but adaptation and agricultural development offer opportunities to overcome these challenges.
Projections for the U.S. show a central tendency of increases in water stress between 2015 and 2050 for much of eastern half of the country and the far west, and a slight reduction in water stress for the upper plains and lower western mountains.
Projections for agricultural production and prices reflect the effects of the Paris Agreement on energy and land-use decisions. Results show that at the global level between 2015 and 2050, the value of overall food production increases by about 130 percent, crop production increases by 75 percent and livestock production by 120 percent. Simulating yield effects of climate change ranging from reductions of approximately 5 percent to about 25 percent varying by crop, livestock type, and region drawn from studies reviewed by the IPCC, the Outlook finds that commodity prices increase above the baseline projection by about 4-7 percent by 2050 for major crops, 25-30 percent for livestock and forestry products, and less than 5 percent for other crops and food.
Emissions and climate projections
Total global emissions of greenhouse gases remain essentially unchanged through 2030, but gradually increase thereafter (rising by about 33 percent between 2015 and 2100) as regions of the world that have not adopted absolute emissions constraints see emissions increases. Future emissions growth will increase the risks associated with global environmental change.
The projected median increase in global mean surface temperature by 2100, above the 1861-1880 mean value, is 3.0 C (the 10 and 90 percent confidence limits of the distribution are 2.6 and 3.5 C). Other important projected changes in the Earth system include: a median ocean pH drop to 7.85 from a preindustrial level of 8.14 in 1861 and, relative to 1861-1880 mean values, a median global precipitation increase of 0.18 millimeters per day and median sea-level rise of 0.23 meters in 2100. The latter figure, based solely on thermal expansion, will likely be higher due to contributions from melting glaciers and ice sheets.
Prospects for meeting near- and long-term Paris goals
The MIT Joint Program invited leading experts on policy developments around the world to provide their perspectives on how well key countries and regions are progressing in fulfilling their NDCs. They report on some bright prospects, including expectations that China may exceed its commitments and that India is on a course to meet its goals. But they also observe a number of dark clouds, from U.S. climate policy developments to the increasing likelihood that financing to assist the least developed countries in sustainable development will not be forthcoming at the levels needed.
Looking at the long-term, the 2018 Outlook finds that the Paris Agreement’s ambitious targets of keeping global warming well below 2 C and ideally below 1.5 C remain technically achievable, but require much deeper, more near-term reductions than those embodied in current NDCs. Making deeper cuts immediately (2020) rather than as a next step in the Paris process (waiting until 2030) would lower the carbon prices needed to achieve long-term goals, and lessen the need for unproven options to achieve zero or negative emissions after 2050.
“More aggressive action sooner rather than later on mitigation will give us a better chance of meeting the long-term targets,” says MIT Joint Program co-director John Reilly. “At the same time, we need to prepare our homes, communities and the industries on which we depend for the climate change we will experience, even if we manage to hold the increase to less than 2 or 1.5 degrees, and make even greater preparations to account for the risk that we may fail to hold the line on the temperature rise.” |
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