Image of the Day: Spectacular storm clouds

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This picture of a storm cloud was taken during the Verification of the Origins of Rotation in Tornadoes Experiment 2, or VORTEX2, project between 2009 and 2010. VORTEX2 explored tornadoes, their origins, their structure and evolution, and how to increase the accuracy and timeliness of tornado forecasts and warnings. VORTEX2 was designed to improve the understanding of tornadogenesis, allowing us to assess the likelihood of tornadoes in supercell thunderstorms.

Image credit: University Corporation for Atmospheric Research

Report: Unless we change direction, the world will warm 3-5 degrees Celsius

Global temperature is likely to rise 3.3-5.6 degrees Celsius by the end of this century, unless international climate negotiations in Paris next year are more effective than expected, according to a report released Monday by the MIT Joint Program on the Science and Policy of Global Change. The predicted temperature increase surpasses the threshold identified by the United Nations as necessary to avoid the most serious impacts of climate change, altering precipitation patterns and heightening the pressures of population and economic growth.

“Our world is rapidly changing,” says John Reilly, co-director of the MIT Joint Program and a coauthor of the report. “We need to understand the nature of the risks we’re facing so we can prepare for them.”

Publication of the report, “2014 Climate and Energy Outlook,” comes on the heels of last week’s UN Climate Summit in New York City, where more than 120 heads of state gathered in preparation for climate negotiations next year. The agreement that comes out of the 2015 talks will inform global climate action after 2020, when existing measures agreed to in Copenhagen and Cancun expire.

The outlook report extends the existing measures after they end to evaluate global changes under possible post-2020 climate action. It uses UN population data and projects economic growth to explore the connections between socioeconomic factors and changing climate, land use, and water. 

“Population and economic growth are key drivers of change,” Reilly says. “Developing countries like China and India are growing fast, and will play a big role in future emissions. They’re also facing the unique challenge of trying to plan for this growth under a changing climate.”

The MIT team expects world energy use to double by 2050, largely due to increased energy use in developing countries, where booming industry and larger, wealthier populations will have more access to personal vehicles. Globally, clean energy sources will make some headway, but energy use will continue to be largely dominated by fossil fuels. As a result, global emissions are expected to double by the end of the century. To stay below the warming threshold, global emissions need to peak soon, if not immediately, the report concludes.

The outlook also examines a more ambitious climate agreement, based on expectations of what countries might pledge in the 2015 climate talks. The more ambitious pledges will further reduce greenhouse gas emissions, it finds, but even with these pledges the world will release enough greenhouse gases by 2040 to make it unlikely that warming will stop at 2 C. 

“There is some uncertainty associated with these estimates,” says Erwan Monier, a research scientist at the Joint Program and a coauthor of the report. “The fact is that there is uncertainty about future emissions, and also in the climate’s response to those emissions. Yet, it is clear that we are not meeting the 2 C target based on current efforts alone.”

New this year is a focus on how these changes impact water resources, which will have to support a growing population’s need for food and energy. The “2014 Climate and Energy Outlook” evaluates water stress, or the amount of water used in an area for irrigation, industry, and household use, compared with how much freshwater is available in that area.

By the end of the century, freshwater supplies will increase 15 percent as hotter temperatures speed up the hydrological cycle, leading to more rain and snow. Global water use will keep pace, and is expected to increase 19 percent.

Water use is expected to skyrocket in India, China, parts of the Middle East, and North Africa, even though some of these countries, like India, will see more rain and snow. Hotter temperatures will lead to more precipitation, but it may fall at the wrong time of the year, after the growing season is over, or may runoff into the ocean.

Globally, most water is used for irrigation. As industrial and household water use grow, they can edge out irrigation, just as more water is needed for irrigation to feed more people.

“These pressures on water will mean increased focus on making sure there is enough water where and when it is needed,” says Charles Fant, a postdoctoral associate at the Joint Program and a coauthor of the report. “This can be done by transporting water to where it is needed, building more storage, or conservation and efficiency efforts.”

Solutions like these are often difficult to put in place, Fant cautions, as they are expensive and may be damaging to the environment.

“Preparing for these issues now simplifies things quite a lot for the future,” Fant says.

By Audrey Resutek | MIT Joint Program on the Science and Policy of Global Change

Image of the Day: The universe at 7.7 billion years old

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This is a simulation of the early life of our universe run on the Argonne National Laboratory’s supercomputer Mira. The simulation starts at 5.6 million years after the big bang and goes to almost 8 billion years later. The full simulation contains 1.1 trillion dark matter particles and shows the universe at 13 billion light-years across. Mira has a little over 262 thousand processors that ran 24 hours a day for two weeks, so the entire simulation took 88 million computing hours to complete. On a single-processor laptop, it would have taken 10,000 years.

Image credit: H. Finkel, S. Habib, K. Heitmann, K. Kumaran, V. Morozov, T. Peterka, A. Pope, T. Williams, M. Papka, M. Hereld, and J. Insley, Argonne National Laboratory; D. Daniel, P. Fasel, N. Frontiere, Los Alamos National Laboratory; and Z. Lukic, Lawrence Berkeley National Laboratory. Figures compiled by Argonne scientists Joe Insley, Katrin Heitmann, and Salman Habib.

Tom Hughes: Remembering a non-lifer

Thomas Hughes, a Distinguished Visiting Professor at MIT and Mellon Professor Emeritus of the History of Science at the University of Pennsylvania, passed away Feb. 3, 2014 at age 89. Hughes, who pioneered the field of the history of technology, was also a founder of the Society for the History of Technology. Below is a reflection on his life and contributions by his MIT colleague Rosalind Williams, the Bern Dibner Professor of the History of Science and Technology. 

MIT is justifiably proud of its “lifers”: individuals who enter MIT as freshmen, continue here for graduate school, join the faculty, and live out their entire professional lives under the Great Dome. In some cases — Paul Gray and Sheila Widnall come to mind — the character of the individual becomes so intertwined with the character of the Institute that it becomes hard to know where one stops and the other begins.

Thomas Parke Hughes (1923-2014) was a non-lifer. He came to MIT in the 1960s for a short stint as an assistant professor. He soon moved on to other institutions, where over time he developed into the nation’s pre-eminent historian of technology. When he returned to MIT as a Distinguished Visiting Professor in the 1990s and early 2000s, he brought with him a deep understanding of how the history of technology transforms our understanding of general history, as well as of the role and responsibilities of engineering. 

Would he have developed such perspectives if he had spent his whole career at MIT? This is an unanswerable question, but without question Tom Hughes reminds us of the invigorating role of non-lifers in our community.

The nation’s pre-eminent historian of technology 

Born and raised in Richmond, Va., Thomas Parke Hughes served in the U.S. Navy during World War II before earning his undergraduate degree in mechanical engineering at the University of Virginia. He stayed there to get his doctorate in modern European history in 1953. Tom came to MIT in the mid-1960s, when the relatively new School of Humanities and Social Science was trying to figure out how to stock a faculty for an amorphous Course XXI. He was part of a cohort of 13 junior faculty; only one of them (Bruce Mazlish, in history) was ultimately tenured. Along with the rest, Tom departed MIT, first for a temporary appointment at Johns Hopkins University and then for a professorship at Southern Methodist University.

At SMU, Tom published a biography of Elmer Sperry (1971), still valuable reading for anyone interested in engineering control systems and their role in 20th-century history. Primarily on the strength of this acclaimed study, he was invited to become a professor in the Department of the History and Sociology of Science at the University of Pennsylvania. He was 50 years old when he accepted the appointment, which elevated both him and the department to academic fame and glory. Graduate students applied to Penn to work with Tom, and the Philadelphia area became a magnet for historians of technology.

Conceptualizing technological systems, defining structures of modern life 

Tom sealed his pre-eminence in the field with the 1983 publication of “Networks of Power: Electrification in Western Society, 1880-1930.” This was more than a comparative history of electrification in the United States, Britain, and Germany: It was also a manifesto declaring the concept of technological systems, which reoriented the history of technology from a focus on the invention of devices to a focus on the construction of large complex systems. Because such systems are defining structures of modern life, this reorientation confirmed the history of technology as an element of general history.

Tom began to write for broader audiences, most notably in “American Genesis: A Century of Invention and Technological Enthusiasm, 1870-1970″ (1989), which was a finalist for the 1990 Pulitzer Prize in history. Also in 1990, Tom returned to MIT as a visiting professor. He taught here for a semester and returned for shorter visits to help supervise graduate students and to run workshops on technological systems. The latter involved faculty from across the Institute, especially from the Program in Science, Technology, and Society and from the School of Engineering. 

An enduring affinity for MIT

After retiring from Penn in 1994, Tom was elevated to Distinguished Visiting Professor at MIT, and spent even more time here. In 1998, he was on campus for two months giving a series of lectures on “open technological systems,” which he defined as ones exhibiting “a complex mix of technical, economic, political, social, and environmental factors.” His favorite example was the Central Artery and Tunnel (CAT, better known as Boston’s “Big Dig”), with Fred Salvucci playing the role as chief system-builder. The CAT, along with the SAGE computer-based defense system and ARPANET, were featured in Tom’s book “Rescuing Prometheus” (1998), an influential cluster of case studies of open technological systems.

In a 2002 email to Philip Khoury (then dean of the School of Humanities, Arts, and Social Sciences) requesting a renewal of his visiting appointment, Tom wrote: “I am so pleased to have the MIT appointment. For years, even decades, I have felt close to MIT, sharing its notable achievements and sensing its problems and opportunities.”

He went on to explain why he felt this closeness: “Over the years, I have tried to understand the character of the engineering profession and, in a limited way, broaden its horizons by helping it to see the central role and daunting responsibilities that it has in the modern world. Engineers lament that they are not appreciated. They do not need the appreciation of others so much as they need secure self-esteem. This would come, I believe, if they accepted the messy complexity and moral dimensions of their calling.”

Technology as a part of a broader human history

Tom was already engaged with the problems and opportunities of engineering when I first met him in the mid-1960s, as a Radcliffe College senior serving him as a research assistant. I enjoyed visiting Tom to discuss my assignments, but the questions he asked me to research were sober and difficult. The imprint of World War II was pronounced. He was already studying the Manhattan Project as an engineering project, a topic he later wrote about in “American Genesis.” He was also, with obvious emotional difficulty, trying to understand the mechanisms of slaughter used in the Holocaust. Many years later I heard him discuss in a seminar the concept of “technological sin” as something both historians and engineers need to contemplate, because the historical world is a sinful one. 

Like William Barton Rogers himself, Tom Hughes came to MIT from Virginia with a vision of what technology and engineering mean in the broad context of human experience. Providing scholarly grounding for that vision was a difficult problem — but Tom would quote Sperry to the effect that he chose the most difficult problems because doing this was a way to avoid vulgar competition.

It took Tom many years in the academic wilderness to redefine technological systems and engineering practice as part of larger history. These views do not come naturally to MIT. We have too much invested in defining engineering as a specialized or semispecialized activity that brings order and moral clarity to the world. But engineering cannot assume “the central role and daunting responsibilities that it has in the modern world” unless we confront its messy complexities and moral ambiguities. They inevitably arise because engineering is inseparable from political, economic, social, and legal structures and activities. By reminding us of this broad historical perspective, Tom Hughes, MIT non-lifer, made an immeasurable contribution to the life of the Institute.

_________________________________________________________________________________

Prepared by MIT SHASS Communications
Communication and Design Director: Emily Hiestand
Associate News Manager: Kathryn O’Neill
Communications Assistant: Kierstin Wesolowski 

By School of Humanities, Arts, and Social Sciences

How to make stronger, “greener” cement

Concrete is the world’s most-used construction material, and a leading contributor to global warming, producing as much as one-tenth of industry-generated greenhouse-gas emissions. Now a new study suggests a way in which those emissions could be reduced by more than half — and the result would be a stronger, more durable material.

The findings come from the most detailed molecular analysis yet of the complex structure of concrete, which is a mixture of sand, gravel, water, and cement. Cement is made by cooking calcium-rich material, usually limestone, with silica-rich material — typically clay — at temperatures of 1,500 degrees Celsius, yielding a hard mass called “clinker.” This is then ground up into a powder. The decarbonation of limestone, and the heating of cement, are responsible for most of the material’s greenhouse-gas output.

The new analysis suggests that reducing the ratio of calcium to silicate would not only cut those emissions, but would actually produce better, stronger concrete. These findings are described in the journal Nature Communications by MIT senior research scientist Roland Pellenq; professors Krystyn Van Vliet, Franz-Josef Ulm, Sidney Yip, and Markus Buehler; and eight co-authors at MIT and at CNRS in Marseille, France.

“Cement is the most-used material on the planet,” Pellenq says, noting that its present usage is estimated to be three times that of steel. “There’s no other solution to sheltering mankind in a durable way — turning liquid into stone in 10 hours, easily, at room temperature. That’s the magic of cement.”

In conventional cements, Pellenq explains, the calcium-to-silica ratio ranges anywhere from about 1.2 to 2.2, with 1.7 accepted as the standard. But the resulting molecular structures have never been compared in detail. Pellenq and his colleagues built a database of all these chemical formulations, finding that the optimum mixture was not the one typically used today, but rather a ratio of about 1.5.

As the ratio varies, he says, the molecular structure of the hardened material progresses from a tightly ordered crystalline structure to a disordered glassy structure. They found the ratio of 1.5 parts calcium for every one part silica to be “a magical ratio,” Pellenq says, because at that point the material can achieve “two times the resistance of normal cement, in mechanical resistance to fracture, with some molecular-scale design.”

The findings, Pellenq adds, were “validated against a large body of experimental data.” Since emissions related to concrete production are estimated to represent 5 to 10 percent of industrial greenhouse-gas emissions, he says, “any reduction in calcium content in the cement mix will have an impact on the CO2.” In fact, he says, the reduction in carbon emissions could be as much as 60 percent.

In addition to the overall improvement in mechanical strength, Pellenq says, because the material would be more glassy and less crystalline, there would be “no residual stresses in the material, so it would be more fracture-resistant.”

The work is the culmination of five years of research by a collaborative team from MIT and CNRS, where Pellenq is research director. The two institutions have a joint laboratory at MIT called the Multi-Scale Materials Science for Energy and Environment, run by Pellenq and Ulm, who is director of MIT’s Concrete Sustainability Hub, and hosted by the MIT Energy Initiative.

Because of its improved resistance to mechanical stress, Pellenq says the revised formulation could be of particular interest to the oil and gas industries, where cement around well casings is crucial to preventing leakage and blowouts. “More resistant cement certainly is something they would consider,” Pellenq says.

So far, the work has remained at the molecular level of analysis, he says. “Next, we have to make sure these nanoscale properties translate to the mesoscale” — that is, to the engineering scale of applications for infrastructure, housing, and other uses.

Zdeněk Bažant, a professor of civil and environmental engineering, mechanical engineering, and materials science and engineering at Northwestern University who was not involved in this research, says, “Roland Pellenq, with his group at MIT, is doing cutting-edge research, clarifying the nanostructure and properties of cement hydrates.”

The Concrete Sustainability Hub is supported by the Portland Cement Association and the Ready Mixed Concrete Research and Education Foundation.

By David L. Chandler | MIT News Office

Image of the Day: The happy seal

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Although only six of the 35 species of seals live in Antarctica, Antarctic seals make up a majority of the world’s seal population. All of the seals in Antarctica are true seals, meaning they have no ears. Despite these missing ears, seal hearing out of the water is as good as human’s, and in the water, it’s even better. Unlike their northern cousins, Antarctic seals have no natural land predators, making them almost fearless of humans.

Image credit: Tim Nash, National Science Foundation

How to make stronger, “greener” cement

Concrete is the world’s most-used construction material, and a leading contributor to global warming, producing as much as one-tenth of industry-generated greenhouse-gas emissions. Now a new study suggests a way in which those emissions could be reduced by more than half — and the result would be a stronger, more durable material.

The findings come from the most detailed molecular analysis yet of the complex structure of concrete, which is a mixture of sand, gravel, water, and cement. Cement is made by cooking calcium-rich material, usually limestone, with silica-rich material — typically clay — at temperatures of 1,500 degrees Celsius, yielding a hard mass called “clinker.” This is then ground up into a powder. The decarbonation of limestone, and the heating of cement, are responsible for most of the material’s greenhouse-gas output.

The new analysis suggests that reducing the ratio of calcium to silicate would not only cut those emissions, but would actually produce better, stronger concrete. These findings are described in the journal Nature Communications by MIT senior research scientist Roland Pellenq; professors Krystyn Van Vliet, Franz-Josef Ulm, Sidney Yip, and Markus Buehler; and eight co-authors at MIT and at CNRS in Marseille, France.

“Cement is the most-used material on the planet,” Pellenq says, noting that its present usage is estimated to be three times that of steel. “There’s no other solution to sheltering mankind in a durable way — turning liquid into stone in 10 hours, easily, at room temperature. That’s the magic of cement.”

In conventional cements, Pellenq explains, the calcium-to-silica ratio ranges anywhere from about 1.2 to 2.2, with 1.7 accepted as the standard. But the resulting molecular structures have never been compared in detail. Pellenq and his colleagues built a database of all these chemical formulations, finding that the optimum mixture was not the one typically used today, but rather a ratio of about 1.5.

As the ratio varies, he says, the molecular structure of the hardened material progresses from a tightly ordered crystalline structure to a disordered glassy structure. They found the ratio of 1.5 parts calcium for every one part silica to be “a magical ratio,” Pellenq says, because at that point the material can achieve “two times the resistance of normal cement, in mechanical resistance to fracture, with some molecular-scale design.”

The findings, Pellenq adds, were “validated against a large body of experimental data.” Since emissions related to concrete production are estimated to represent 5 to 10 percent of industrial greenhouse-gas emissions, he says, “any reduction in calcium content in the cement mix will have an impact on the CO2.” In fact, he says, the reduction in carbon emissions could be as much as 60 percent.

In addition to the overall improvement in mechanical strength, Pellenq says, because the material would be more glassy and less crystalline, there would be “no residual stresses in the material, so it would be more fracture-resistant.”

The work is the culmination of five years of research by a collaborative team from MIT and CNRS, where Pellenq is research director. The two institutions have a joint laboratory at MIT called the Multi-Scale Materials Science for Energy and Environment, run by Pellenq and Ulm, who is director of MIT’s Concrete Sustainability Hub, and hosted by the MIT Energy Initiative.

Because of its improved resistance to mechanical stress, Pellenq says the revised formulation could be of particular interest to the oil and gas industries, where cement around well casings is crucial to preventing leakage and blowouts. “More resistant cement certainly is something they would consider,” Pellenq says.

So far, the work has remained at the molecular level of analysis, he says. “Next, we have to make sure these nanoscale properties translate to the mesoscale” — that is, to the engineering scale of applications for infrastructure, housing, and other uses.

Zdeněk Bažant, a professor of civil and environmental engineering, mechanical engineering, and materials science and engineering at Northwestern University who was not involved in this research, says, “Roland Pellenq, with his group at MIT, is doing cutting-edge research, clarifying the nanostructure and properties of cement hydrates.”

The Concrete Sustainability Hub is supported by the Portland Cement Association and the Ready Mixed Concrete Research and Education Foundation.

By David L. Chandler | MIT News Office

Image of the Day: Blue flame, stained glass

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This isn’t actually a stained glass mosaic, but individual grains of strengthened copper. The largest orange blobs are about the size of a fine human hair. The dappled pattern came from applying ferric acid, which ate through the metal but left some copper crystallites behind.

Image credit: Gary Navrotski, Mike Bosek, Jeff Collins, Jeremy Nudell, Ali Khounsary, Bran Brajuskovic, Patric Den Hartog and John Quintana

More than a prize

Bright and early on Saturday, Sept. 27, 2014, more than 200 mathletes will converge on the MIT campus to compete in the world’s largest mathematics competition for young women in high school, the Advantage Testing Foundation’s Math Prize for Girls.

Joining them will be Sindy Tan, an undergraduate at Harvard University and a volunteer for the Math Prize for Girls. Tan herself is a veteran of math competitions, having participated in her first competition in the eighth grade and continuing all through high school. Math competitions were central to Tan’s growing love of math. They gave her the chance to build a tool box of powerful problem-solving concepts and to use them in creative ways. She was excited to meet other talented people who also appreciated the beauty of math and who were eager to share their own imaginative ways of solving problems.

But when Tan looked around at her peers on the competition circuit, she didn’t find very many other women and girls. There was nothing to counter the sense of being surrounded by “boys, boys, and boys,” Tan says.

That is, until Tan was invited to compete in the Math Prize for Girls for the first time in 2011 and again in 2013. She found a community of girls and women who loved math and encouraged each other to pursue it. Now she is back to help other girls have the same inspiring experience she did.

The Math Prize for Girls was established in 2009 by Ravi Boppana, the co-director of mathematics at Advantage Testing, with the aim of bringing math-minded girls together, inspiring them to pursue their love of mathematics, and encouraging them to become mentors to others. After New York University hosted the competition for its first two years, the Math Prize for Girls has been held at MIT since 2011. Two professors from the MIT Department of Mathematics, Gigliola Staffilani and Michael Sipser — who is also dean of the School of Science — serve on the competition’s board of advisors.

“I am impressed by the achievements and enthusiasm of the Math Prize for Girls competitors,” says Sipser. “I am delighted that we have the opportunity to support the girls in their growth as problem solvers and mentors. I look forward to seeing what they accomplish in the future — and hope that many of them will come to MIT as students or faculty someday.”

In many ways, the Math Prize for Girls is not very different from other high school math competitions. Participants, who qualify by taking the American Mathematics Competition exam, must complete 20 short-answer problems in geometry, algebra, and trigonometry in 150 minutes. The exams are then reviewed by a panel of judges, who award a cash prizes to the top-scoring participants — in this case, $25,000 for first place, $10,000 for second place, and $5,000 for third place. 

But as the girls enjoy Games Night at Microsoft the evening before the competition, and while they wait nervously for their scores after they take the test, the girls will have an opportunity to meet new like-minded people, see old friends, and — of course — talk about math. They will begin to build a network of peers that will last into their college years and beyond.

Melody Guan, another Harvard undergraduate and Math Prize for Girls alumna believes that networking and mentorship are important tools for encouraging girls and women to keep pursuing their love of math.

“Math remains a male-dominated field,” says Guan, “so being a female mathlete can be a lonesome and isolating experience, which can turn girls off to math.”

However, finding a network of other women and girls who share a passion for mathematics can be a powerful experience — one that helps many girls pursue their interests in mathematics and other science fields in the long run. Guan thinks that this is why the community of girls brought together by the Math Prize for Girls is so important.

“Indeed, while there is an increasing number of successful female mathematicians who can serve as fantastic role models for math-loving girls — the most recent example being Fields Medalist Maryam Mirzahkani — they can be seen as the exception rather than the rule,” says Guan. “And in a way, there is nothing quite as empowering as finding yourself in a huge auditorium surrounded by other girls who love and rock math.”

Where Tan and Guan are concerned, the Math Prize for Girls has succeeded in its mission of inspiring girls to pursue math and science and in building a network of peers and mentors. Tan, still in her first year at Harvard, hasn’t declared her major yet, but is considering math and is a co-organizer of the Harvard-MIT Math Tournament, a semi-annual competition for high school and middle school students. Guan, in her third year at Harvard, is studying chemistry, physics, and statistics, and is an undergraduate researcher at the Harvard Stem Cell Institute. Guan assists at math camps, serves as a board member at the Harvard-MIT Math Tournament, has designed and taught high school math and science classes through the MIT Educational Studies Program, and has been a course assistant to her fellow students at Harvard. They will both be volunteering at the Math Prize for Girl on Saturday.

To learn more about how you can support the Math Prize for Girls, please visit their their website.

By Bendta Schroeder | School of Science

Image of the Day: Orion ‘bullets’

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In this image of the Orion Nebula, the blue spots are clouds of gaseous iron “bullets” being propelled at supersonic speeds from a region of massive star formation outside and below this image’s field of view. As these bullets pass through neutral hydrogen gas, it heats up the hydrogen and produces the pillars that trace the passage of the iron clouds.

Image credit: Gemini Observatory/AURA 2013.01.09

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