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  • richardmitnick 11:31 am on July 11, 2021 Permalink | Reply
    Tags: "Huge Volcanic Eruption Disrupted Climate but Not Human Evolution", , , , , Paleoclimatology, , , The Toba volcano was the largest volcanic eruption in the past two million years.   

    From Rutgers University (US) : “Huge Volcanic Eruption Disrupted Climate but Not Human Evolution” 

    Rutgers smaller
    Our Great Seal.

    From Rutgers University (US)

    July 9, 2021
    John Cramer
    jdc268@echo.rutgers.edu

    1
    A modern volcanic eruption pales in comparison to the Toba eruption, which was the largest volcanic eruption of the past 2 million years, dispersing ash as far as southern Africa 9,000 km away. The total volume of erupted deposits may exceed 5,000 cubic kilometers. Credit: Steve Self, University of California-Berkeley (US).

    A massive volcanic eruption in Indonesia about 74,000 years ago likely caused severe climate disruption in many areas of the globe, but early human populations were sheltered from the worst effects, according to a Rutgers-led study.

    The findings appear in the journal PNAS.

    The eruption of the Toba volcano was the largest volcanic eruption in the past two million years, but its impacts on climate and human evolution have been unclear. Resolving this debate is important for understanding environmental changes during a key interval in human evolution.

    “We were able to use a large number of climate model simulations to resolve what seemed like a paradox,” said lead author Benjamin Black, an assistant professor in the Department of Earth and Planetary Sciences at Rutgers University-New Brunswick. “We know this eruption happened and that past climate modeling has suggested the climate consequences could have been severe, but archaeological and paleoclimate records from Africa don’t show such a dramatic response.

    “Our results suggest that we might not have been looking in the right place to see the climate response. Africa and India are relatively sheltered, whereas North America, Europe and Asia bear the brunt of the cooling,” Black said. “One intriguing aspect of this is that Neanderthals and Denisovans were living in Europe and Asia at this time, so our paper suggests evaluating the effects of the Toba eruption on those populations could merit future investigation.”

    2
    The researchers examined explosive ash deposits that are tens of meters thick about 35 km north of the Toba caldera in Indonesia. Credit Steve Self, University of California-Berkeley.

    The researchers analyzed 42 global climate model simulations in which they varied magnitude of sulfur emissions, time of year of the eruption, background climate state and sulfur injection altitude to make a probabilistic assessment of the range of climate disruptions the Toba eruption may have caused. This approach let the team account for some of the unknowns related to the eruption.

    “By using a probabilistic approach, we aim at understanding the likelihood that some regions were less impacted by Toba, considering the wide range of estimates of its size and timing, in addition to our lack of knowledge of the underlying climate state,” said Black.

    The results suggest there was likely significant regional variation in climate impacts. The simulations predict cooling in the Northern Hemisphere of at least 4°C, with regional cooling as high as 10°C depending on the model parameters. In contrast, even under the most severe eruption conditions, cooling in the Southern Hemisphere — including regions populated by early humans — was unlikely to exceed 4°C, although regions in southern Africa and India may have seen decreases in precipitation at the highest sulfur emission level.

    The results explain independent archaeological evidence suggesting the Toba eruption had modest effects on the development of hominid species in Africa. According to the authors, their ensemble simulation approach could be used to better understand other past and future explosive eruptions.

    “Our results reconcile the simulated distribution of climate impacts from the eruption with paleoclimate and archaeological records,” according to the study. “This probabilistic view of climate disruption from Earth’s most recent super-eruption underscores the uneven expected distribution of societal and environmental impacts from future very large explosive eruptions.”

    The study included researchers from the National Center for Atmospheric Research, University of Leeds and University of Cambridge, and was supported by the NSF National Center for Atmospheric Research (US) and the National Science Foundation (US).

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    rutgers-campus

    Rutgers, The State University of New Jersey (US), is a leading national research university and the state’s preeminent, comprehensive public institution of higher education. Rutgers is dedicated to teaching that meets the highest standards of excellence; to conducting research that breaks new ground; and to providing services, solutions, and clinical care that help individuals and the local, national, and global communities where they live.

    Founded in 1766, Rutgers teaches across the full educational spectrum: preschool to precollege; undergraduate to graduate; postdoctoral fellowships to residencies; and continuing education for professional and personal advancement.

    Rutgers University (US) is a public land-grant research university based in New Brunswick, New Jersey. Chartered in 1766, Rutgers was originally called Queen’s College, and today it is the eighth-oldest college in the United States, the second-oldest in New Jersey (after Princeton University (US)), and one of the nine U.S. colonial colleges that were chartered before the American War of Independence. In 1825, Queen’s College was renamed Rutgers College in honor of Colonel Henry Rutgers, whose substantial gift to the school had stabilized its finances during a period of uncertainty. For most of its existence, Rutgers was a private liberal arts college but it has evolved into a coeducational public research university after being designated The State University of New Jersey by the New Jersey Legislature via laws enacted in 1945 and 1956.

    Rutgers today has three distinct campuses, located in New Brunswick (including grounds in adjacent Piscataway), Newark, and Camden. The university has additional facilities elsewhere in the state, including oceanographic research facilities at the New Jersey shore. Rutgers is also a land-grant university, a sea-grant university, and the largest university in the state. Instruction is offered by 9,000 faculty members in 175 academic departments to over 45,000 undergraduate students and more than 20,000 graduate and professional students. The university is accredited by the Middle States Association of Colleges and Schools and is a member of the Big Ten Academic Alliance, the Association of American Universities (US) and the Universities Research Association (US). Over the years, Rutgers has been considered a Public Ivy.

    Research

    Rutgers is home to the Rutgers University Center for Cognitive Science, also known as RUCCS. This research center hosts researchers in psychology, linguistics, computer science, philosophy, electrical engineering, and anthropology.

    It was at Rutgers that Selman Waksman (1888–1973) discovered several antibiotics, including actinomycin, clavacin, streptothricin, grisein, neomycin, fradicin, candicidin, candidin, and others. Waksman, along with graduate student Albert Schatz (1920–2005), discovered streptomycin—a versatile antibiotic that was to be the first applied to cure tuberculosis. For this discovery, Waksman received the Nobel Prize for Medicine in 1952.

    Rutgers developed water-soluble sustained release polymers, tetraploids, robotic hands, artificial bovine insemination, and the ceramic tiles for the heat shield on the Space Shuttle. In health related field, Rutgers has the Environmental & Occupational Health Science Institute (EOHSI).

    Rutgers is also home to the RCSB Protein Data bank, “…an information portal to Biological Macromolecular Structures’ cohosted with the San Diego Supercomputer Center (US). This database is the authoritative research tool for bioinformaticists using protein primary, secondary and tertiary structures worldwide….”

    Rutgers is home to the Rutgers Cooperative Research & Extension office, which is run by the Agricultural and Experiment Station with the support of local government. The institution provides research & education to the local farming and agro industrial community in 19 of the 21 counties of the state and educational outreach programs offered through the New Jersey Agricultural Experiment Station Office of Continuing Professional Education.

    Rutgers University Cell and DNA Repository (RUCDR) is the largest university based repository in the world and has received awards worth more than $57.8 million from the National Institutes of Health (US). One will fund genetic studies of mental disorders and the other will support investigations into the causes of digestive, liver and kidney diseases, and diabetes. RUCDR activities will enable gene discovery leading to diagnoses, treatments and, eventually, cures for these diseases. RUCDR assists researchers throughout the world by providing the highest quality biomaterials, technical consultation, and logistical support.

    Rutgers–Camden is home to the nation’s PhD granting Department of Childhood Studies. This department, in conjunction with the Center for Children and Childhood Studies, also on the Camden campus, conducts interdisciplinary research which combines methodologies and research practices of sociology, psychology, literature, anthropology and other disciplines into the study of childhoods internationally.

    Rutgers is home to several National Science Foundation (US) IGERT fellowships that support interdisciplinary scientific research at the graduate-level. Highly selective fellowships are available in the following areas: Perceptual Science, Stem Cell Science and Engineering, Nanotechnology for Clean Energy, Renewable and Sustainable Fuels Solutions, and Nanopharmaceutical Engineering.

    Rutgers also maintains the Office of Research Alliances that focuses on working with companies to increase engagement with the university’s faculty members, staff and extensive resources on the four campuses.

    As a ’67 graduate of University College, second in my class, I am proud to be a member of

    Alpha Sigma Lamda, National Honor Society of non-tradional students.

     
  • richardmitnick 8:38 pm on June 16, 2021 Permalink | Reply
    Tags: "Imagining the distant past — and finding keys to the future", , EAPS: MIT’s Department of Earth Atmospheric and Planetary Sciences, , , , , , MIT Terrascope, Paleoclimatology, Terrascope is one of four learning communities offered to first-year MIT students., Working with cores of sediment drilled from the Earth that hold clues to our planet’s climate long before there were records created by humans., You’re able to go basically from mud to a coherent picture of what the atmosphere was doing in the past-what the ocean was doing in the past.   

    From Massachusetts Institute of Technology (US) : “Imagining the distant past — and finding keys to the future” 

    MIT News

    From Massachusetts Institute of Technology (US)

    June 16, 2021
    Michaela Jarvis

    1
    MIT earth science professor David McGee studies the atmosphere’s response to paleoclimate changes. “A really basic message that comes from the study of paleoclimate is the sensitivity of the Earth’s system,” he says. “A few degrees of warming or cooling is a really big deal.” Credit: Adam Glanzman.

    The most dramatic moments of David McGee’s research occur when he is working with cores of sediment drilled from the Earth that hold clues to our planet’s climate long before there were records created by humans.

    “Some of the biggest excitement I have,” says McGee, an associate professor in MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS), “is when we’re working with sediments that have been taken from 2,000 meters down in the Atlantic Ocean, for example. You’re performing various geochemical measurements on the sediments, you’re using radiocarbon dating to figure how old a core is, and you’re developing records of how the climate has changed over the past thousands of years. You’re able to go basically from mud to a coherent picture of what the atmosphere was doing in the past-what the ocean was doing in the past.”

    Imagining the natural world as it was in the distant past, when no people were around to directly observe or write about it, always fascinated McGee. As a child, before it even occurred to him that there was such a thing as an Earth scientist, he was “constantly wondering about what mountains and beaches would have looked like millions of years ago and what they might look like a million years from now.” Recently, while going through the artifacts of his childhood, he found a rock collection and a creative writing project focused on time travel back to the Precambrian Era. He recalls that once when he was set loose in the school library to find a science project topic, he chose a book on ice ages and tried to develop related hypotheses that he could test.

    Later, stumbling into a geology class in college, as he describes it, McGee was completely taken in by the idea that Earth science involved a sort of detective work to uncover history out in the natural world, using the tools of modern science, such as geochemistry, computation, and close observation.

    “I really fell for it,” he says.

    McGee’s focus on studying paleoclimate and the atmosphere’s response to past climate changes satisfies his lifelong curiosity — and it yields important insights into the climate change the planet is currently undergoing.

    “A really basic message that comes from the study of paleoclimate is the sensitivity of the Earth’s system,” says McGee. “A few degrees of warming or cooling is a really big deal.”

    From the start of his career, McGee has been dedicated to sharing his love of exploration with students. He earned a master’s degree in teaching and spent seven years as a teacher in middle school and high school classrooms before earning his PhD in Earth and environmental sciences from Columbia University. He joined the MIT faculty in 2012 and in 2018 received the Excellence in Mentoring Award from MIT’s Undergraduate Advising and Academic Programming office. In 2019, he was granted tenure.

    In 2016, McGee became the director of MIT’s Terrascope first-year learning community, where he says he has been able to continue to pursue his interest in how students learn.

    1
    MIT Terrascope

    “Part of why Terrascope has been so important to me is it’s a place where there is a lot of great thinking about what makes a meaningful educational experience,” he says.

    Terrascope is one of four learning communities offered to first-year MIT students, allows them to address real-world sustainability issues in interdisciplinary, student-led teams. The projects the students undertake connect them to related experts and professionals, in part so the students can figure out what blend of areas of expertise — such as technology, policy, economics, and human behaviors — will serve them as they head toward their life’s work.

    “Students are often asking themselves, ‘How do I connect what I really like to do, what I’m good at, and what the world actually needs?’” McGee says. “In Terrascope, we try to provide a space for that exploration.”

    McGee’s work with Terrascope was, in part, the basis for his September 2020 appointment to the role of associate department head for diversity, equity, and inclusion within EAPS. On the occasion of McGee’s appointment, EAPS department head Rob van der Hilst said, “David has proven he is a dedicated and compassionate leader, able to build a robust community around collaboration, shared purpose, and deep respect for the strengths each member brings.”

    McGee says Earth science is often unwelcoming to women, members of racial or ethnic minoritized groups, and people who are LGBTQ+. Improved recruitment and retention policies are needed to diversify the field, he says.

    “Earth science is a very white science,” McGee says. “And yet we’re working on problems that affect everyone and disproportionately affect communities of color — things like climate change and natural disasters. It’s really important that the future of Earth science look different than the present in terms of the demographics.”

    One of the things McGee takes from his research experience as he approaches students is his observation that being an Earth scientist represents many different approaches and avenues of study — inherently, the field can extend itself to a wide diversity of talent.

    “The thing I try to make clear to students is there’s no way to be the expert in every aspect of even one Earth science study,” he says. “With the study of paleoclimate, for instance, there’s field geology, careful analytical chemistry, data analysis, computation, the physics of climate systems. You’re constantly on the edge of your learning and working with people who know more than you about a certain aspect of a study. Students are not coming to Earth science to become a carbon copy of any of us.”

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    MIT Seal

    USPS “Forever” postage stamps celebrating Innovation at MIT.

    MIT Campus

    Massachusetts Institute of Technology (US) is a private land-grant research university in Cambridge, Massachusetts. The institute has an urban campus that extends more than a mile (1.6 km) alongside the Charles River. The institute also encompasses a number of major off-campus facilities such as the MIT Lincoln Laboratory, the Bates Center, and the Haystack Observatory, as well as affiliated laboratories such as the Broad and Whitehead Institutes.

    Founded in 1861 in response to the increasing industrialization of the United States, MIT adopted a European polytechnic university model and stressed laboratory instruction in applied science and engineering. It has since played a key role in the development of many aspects of modern science, engineering, mathematics, and technology, and is widely known for its innovation and academic strength. It is frequently regarded as one of the most prestigious universities in the world.

    As of December 2020, 97 Nobel laureates, 26 Turing Award winners, and 8 Fields Medalists have been affiliated with MIT as alumni, faculty members, or researchers. In addition, 58 National Medal of Science recipients, 29 National Medals of Technology and Innovation recipients, 50 MacArthur Fellows, 80 Marshall Scholars, 3 Mitchell Scholars, 22 Schwarzman Scholars, 41 astronauts, and 16 Chief Scientists of the U.S. Air Force have been affiliated with MIT. The university also has a strong entrepreneurial culture and MIT alumni have founded or co-founded many notable companies. MIT is a member of the Association of American Universities (AAU).

    Foundation and vision

    In 1859, a proposal was submitted to the Massachusetts General Court to use newly filled lands in Back Bay, Boston for a “Conservatory of Art and Science”, but the proposal failed. A charter for the incorporation of the Massachusetts Institute of Technology, proposed by William Barton Rogers, was signed by John Albion Andrew, the governor of Massachusetts, on April 10, 1861.

    Rogers, a professor from the University of Virginia (US), wanted to establish an institution to address rapid scientific and technological advances. He did not wish to found a professional school, but a combination with elements of both professional and liberal education, proposing that:

    “The true and only practicable object of a polytechnic school is, as I conceive, the teaching, not of the minute details and manipulations of the arts, which can be done only in the workshop, but the inculcation of those scientific principles which form the basis and explanation of them, and along with this, a full and methodical review of all their leading processes and operations in connection with physical laws.”

    The Rogers Plan reflected the German research university model, emphasizing an independent faculty engaged in research, as well as instruction oriented around seminars and laboratories.

    Early developments

    Two days after MIT was chartered, the first battle of the Civil War broke out. After a long delay through the war years, MIT’s first classes were held in the Mercantile Building in Boston in 1865. The new institute was founded as part of the Morrill Land-Grant Colleges Act to fund institutions “to promote the liberal and practical education of the industrial classes” and was a land-grant school. In 1863 under the same act, the Commonwealth of Massachusetts founded the Massachusetts Agricultural College, which developed as the University of Massachusetts Amherst (US)). In 1866, the proceeds from land sales went toward new buildings in the Back Bay.

    MIT was informally called “Boston Tech”. The institute adopted the European polytechnic university model and emphasized laboratory instruction from an early date. Despite chronic financial problems, the institute saw growth in the last two decades of the 19th century under President Francis Amasa Walker. Programs in electrical, chemical, marine, and sanitary engineering were introduced, new buildings were built, and the size of the student body increased to more than one thousand.

    The curriculum drifted to a vocational emphasis, with less focus on theoretical science. The fledgling school still suffered from chronic financial shortages which diverted the attention of the MIT leadership. During these “Boston Tech” years, MIT faculty and alumni rebuffed Harvard University (US) president (and former MIT faculty) Charles W. Eliot’s repeated attempts to merge MIT with Harvard College’s Lawrence Scientific School. There would be at least six attempts to absorb MIT into Harvard. In its cramped Back Bay location, MIT could not afford to expand its overcrowded facilities, driving a desperate search for a new campus and funding. Eventually, the MIT Corporation approved a formal agreement to merge with Harvard, over the vehement objections of MIT faculty, students, and alumni. However, a 1917 decision by the Massachusetts Supreme Judicial Court effectively put an end to the merger scheme.

    In 1916, the MIT administration and the MIT charter crossed the Charles River on the ceremonial barge Bucentaur built for the occasion, to signify MIT’s move to a spacious new campus largely consisting of filled land on a one-mile-long (1.6 km) tract along the Cambridge side of the Charles River. The neoclassical “New Technology” campus was designed by William W. Bosworth and had been funded largely by anonymous donations from a mysterious “Mr. Smith”, starting in 1912. In January 1920, the donor was revealed to be the industrialist George Eastman of Rochester, New York, who had invented methods of film production and processing, and founded Eastman Kodak. Between 1912 and 1920, Eastman donated $20 million ($236.6 million in 2015 dollars) in cash and Kodak stock to MIT.

    Curricular reforms

    In the 1930s, President Karl Taylor Compton and Vice-President (effectively Provost) Vannevar Bush emphasized the importance of pure sciences like physics and chemistry and reduced the vocational practice required in shops and drafting studios. The Compton reforms “renewed confidence in the ability of the Institute to develop leadership in science as well as in engineering”. Unlike Ivy League schools, MIT catered more to middle-class families, and depended more on tuition than on endowments or grants for its funding. The school was elected to the Association of American Universities (US)in 1934.

    Still, as late as 1949, the Lewis Committee lamented in its report on the state of education at MIT that “the Institute is widely conceived as basically a vocational school”, a “partly unjustified” perception the committee sought to change. The report comprehensively reviewed the undergraduate curriculum, recommended offering a broader education, and warned against letting engineering and government-sponsored research detract from the sciences and humanities. The School of Humanities, Arts, and Social Sciences and the MIT Sloan School of Management were formed in 1950 to compete with the powerful Schools of Science and Engineering. Previously marginalized faculties in the areas of economics, management, political science, and linguistics emerged into cohesive and assertive departments by attracting respected professors and launching competitive graduate programs. The School of Humanities, Arts, and Social Sciences continued to develop under the successive terms of the more humanistically oriented presidents Howard W. Johnson and Jerome Wiesner between 1966 and 1980.

    MIT’s involvement in military science surged during World War II. In 1941, Vannevar Bush was appointed head of the federal Office of Scientific Research and Development and directed funding to only a select group of universities, including MIT. Engineers and scientists from across the country gathered at MIT’s Radiation Laboratory, established in 1940 to assist the British military in developing microwave radar. The work done there significantly affected both the war and subsequent research in the area. Other defense projects included gyroscope-based and other complex control systems for gunsight, bombsight, and inertial navigation under Charles Stark Draper’s Instrumentation Laboratory; the development of a digital computer for flight simulations under Project Whirlwind; and high-speed and high-altitude photography under Harold Edgerton. By the end of the war, MIT became the nation’s largest wartime R&D contractor (attracting some criticism of Bush), employing nearly 4000 in the Radiation Laboratory alone and receiving in excess of $100 million ($1.2 billion in 2015 dollars) before 1946. Work on defense projects continued even after then. Post-war government-sponsored research at MIT included SAGE and guidance systems for ballistic missiles and Project Apollo.

    These activities affected MIT profoundly. A 1949 report noted the lack of “any great slackening in the pace of life at the Institute” to match the return to peacetime, remembering the “academic tranquility of the prewar years”, though acknowledging the significant contributions of military research to the increased emphasis on graduate education and rapid growth of personnel and facilities. The faculty doubled and the graduate student body quintupled during the terms of Karl Taylor Compton, president of MIT between 1930 and 1948; James Rhyne Killian, president from 1948 to 1957; and Julius Adams Stratton, chancellor from 1952 to 1957, whose institution-building strategies shaped the expanding university. By the 1950s, MIT no longer simply benefited the industries with which it had worked for three decades, and it had developed closer working relationships with new patrons, philanthropic foundations and the federal government.

    In late 1960s and early 1970s, student and faculty activists protested against the Vietnam War and MIT’s defense research. In this period MIT’s various departments were researching helicopters, smart bombs and counterinsurgency techniques for the war in Vietnam as well as guidance systems for nuclear missiles. The Union of Concerned Scientists was founded on March 4, 1969 during a meeting of faculty members and students seeking to shift the emphasis on military research toward environmental and social problems. MIT ultimately divested itself from the Instrumentation Laboratory and moved all classified research off-campus to the MIT (US) Lincoln Laboratoryfacility in 1973 in response to the protests. The student body, faculty, and administration remained comparatively unpolarized during what was a tumultuous time for many other universities. Johnson was seen to be highly successful in leading his institution to “greater strength and unity” after these times of turmoil. However six MIT students were sentenced to prison terms at this time and some former student leaders, such as Michael Albert and George Katsiaficas, are still indignant about MIT’s role in military research and its suppression of these protests. (Richard Leacock’s film, November Actions, records some of these tumultuous events.)

    In the 1980s, there was more controversy at MIT over its involvement in SDI (space weaponry) and CBW (chemical and biological warfare) research. More recently, MIT’s research for the military has included work on robots, drones and ‘battle suits’.

    Recent history

    MIT has kept pace with and helped to advance the digital age. In addition to developing the predecessors to modern computing and networking technologies, students, staff, and faculty members at Project MAC, the Artificial Intelligence Laboratory, and the Tech Model Railroad Club wrote some of the earliest interactive computer video games like Spacewar! and created much of modern hacker slang and culture. Several major computer-related organizations have originated at MIT since the 1980s: Richard Stallman’s GNU Project and the subsequent Free Software Foundation were founded in the mid-1980s at the AI Lab; the MIT Media Lab was founded in 1985 by Nicholas Negroponte and Jerome Wiesner to promote research into novel uses of computer technology; the World Wide Web Consortium standards organization was founded at the Laboratory for Computer Science in 1994 by Tim Berners-Lee; the MIT OpenCourseWare project has made course materials for over 2,000 MIT classes available online free of charge since 2002; and the One Laptop per Child initiative to expand computer education and connectivity to children worldwide was launched in 2005.

    MIT was named a sea-grant college in 1976 to support its programs in oceanography and marine sciences and was named a space-grant college in 1989 to support its aeronautics and astronautics programs. Despite diminishing government financial support over the past quarter century, MIT launched several successful development campaigns to significantly expand the campus: new dormitories and athletics buildings on west campus; the Tang Center for Management Education; several buildings in the northeast corner of campus supporting research into biology, brain and cognitive sciences, genomics, biotechnology, and cancer research; and a number of new “backlot” buildings on Vassar Street including the Stata Center. Construction on campus in the 2000s included expansions of the Media Lab, the Sloan School’s eastern campus, and graduate residences in the northwest. In 2006, President Hockfield launched the MIT Energy Research Council to investigate the interdisciplinary challenges posed by increasing global energy consumption.

    In 2001, inspired by the open source and open access movements, MIT launched OpenCourseWare to make the lecture notes, problem sets, syllabi, exams, and lectures from the great majority of its courses available online for no charge, though without any formal accreditation for coursework completed. While the cost of supporting and hosting the project is high, OCW expanded in 2005 to include other universities as a part of the OpenCourseWare Consortium, which currently includes more than 250 academic institutions with content available in at least six languages. In 2011, MIT announced it would offer formal certification (but not credits or degrees) to online participants completing coursework in its “MITx” program, for a modest fee. The “edX” online platform supporting MITx was initially developed in partnership with Harvard and its analogous “Harvardx” initiative. The courseware platform is open source, and other universities have already joined and added their own course content. In March 2009 the MIT faculty adopted an open-access policy to make its scholarship publicly accessible online.

    MIT has its own police force. Three days after the Boston Marathon bombing of April 2013, MIT Police patrol officer Sean Collier was fatally shot by the suspects Dzhokhar and Tamerlan Tsarnaev, setting off a violent manhunt that shut down the campus and much of the Boston metropolitan area for a day. One week later, Collier’s memorial service was attended by more than 10,000 people, in a ceremony hosted by the MIT community with thousands of police officers from the New England region and Canada. On November 25, 2013, MIT announced the creation of the Collier Medal, to be awarded annually to “an individual or group that embodies the character and qualities that Officer Collier exhibited as a member of the MIT community and in all aspects of his life”. The announcement further stated that “Future recipients of the award will include those whose contributions exceed the boundaries of their profession, those who have contributed to building bridges across the community, and those who consistently and selflessly perform acts of kindness”.

    In September 2017, the school announced the creation of an artificial intelligence research lab called the MIT-IBM Watson AI Lab. IBM will spend $240 million over the next decade, and the lab will be staffed by MIT and IBM scientists. In October 2018 MIT announced that it would open a new Schwarzman College of Computing dedicated to the study of artificial intelligence, named after lead donor and The Blackstone Group CEO Stephen Schwarzman. The focus of the new college is to study not just AI, but interdisciplinary AI education, and how AI can be used in fields as diverse as history and biology. The cost of buildings and new faculty for the new college is expected to be $1 billion upon completion.

    The Caltech/MIT Advanced aLIGO (US) was designed and constructed by a team of scientists from California Institute of Technology, MIT, and industrial contractors, and funded by the National Science Foundation (US) .

    MIT/Caltech Advanced aLigo .

    It was designed to open the field of gravitational-wave astronomy through the detection of gravitational waves predicted by general relativity. Gravitational waves were detected for the first time by the LIGO detector in 2015. For contributions to the LIGO detector and the observation of gravitational waves, two Caltech physicists, Kip Thorne and Barry Barish, and MIT physicist Rainer Weiss won the Nobel Prize in physics in 2017. Weiss, who is also an MIT graduate, designed the laser interferometric technique, which served as the essential blueprint for the LIGO.

    The mission of MIT is to advance knowledge and educate students in science, technology, and other areas of scholarship that will best serve the nation and the world in the twenty-first century. We seek to develop in each member of the MIT community the ability and passion to work wisely, creatively, and effectively for the betterment of humankind.

     
  • richardmitnick 10:14 am on February 19, 2021 Permalink | Reply
    Tags: "Ancient relic points to a turning point in Earth's history 42000 years ago", "Laschamps Excursion", "The Hitchhiker’s Guide to the Galaxy", Adams Transitional Geomagnetic Event, , Douglas Adams, Early humans around the world would have seen amazing auroras., , Earth’s magnetic field dropped to only 0-6 per cent strength during the "Adams Event"., Just like in “The Hitchhiker’s Guide to the Galaxy” the answer was 42., Kauri trees encode magnetic pole reversals., Megafauna across mainland Australia and Tasmania went through simultaneous extinctions 42000 years ago., Paleoclimatology, Rresearchers were able to create a detailed timescale of how Earth’s atmosphere changed over this time by analysing rings on the ancient kauri trees., The magnetic north pole-that is the direction a compass needle points to-doesn’t have a fixed location., The weakening of its magnetic field can mean more space weather-like solar flares and galactic cosmic rays-could head Earth’s way., These findings come two years after a particularly important ancient kauri tree was uncovered at Ngāwhā Northland., University of New South Wales(AU)   

    From University of New South Wales(AU): “Ancient relic points to a turning point in Earth’s history 42000 years ago” 

    U NSW bloc

    From University of New South Wales(AU)

    19 Feb 2021
    Sherry Landow

    Just like in The Hitchhiker’s Guide to the Galaxy, the answer was 42.

    1
    This dramatic paleoclimate change – which was hallmarked with widespread auroras – could help explain other evolutionary mysteries, like the extinction of Neanderthals. Credit: Unsplash.

    The temporary breakdown of Earth’s magnetic field 42,000 years ago sparked major climate shifts that led to global environmental change and mass extinctions, a new international study co-led by UNSW Sydney and the South Australian Museum shows.

    This dramatic turning point in Earth’s history – laced with electrical storms, widespread auroras, and cosmic radiation – was triggered by the reversal of Earth’s magnetic poles and changing solar winds.

    The researchers dubbed this danger period the Adams Transitional Geomagnetic Event, or Adams Event for short – a tribute to science fiction writer Douglas Adams, who wrote in The Hitchhiker’s Guide to the Galaxy that ‘42’ was the answer to life, the universe, and everything.

    The findings are published today in Science.

    “For the first time ever, we have been able to precisely date the timing and environmental impacts of the last magnetic pole switch,” says Chris Turney, a professor at UNSW Science and co-lead author of the study.

    2
    This ancient kauri tree found in Ngāwhā, New Zealand, was alive during the Adams Event. Photo: Nelson Parker (http://www.nelsonskaihukauri.co.nz)

    “The findings were made possible with ancient New Zealand kauri trees, which have been preserved in sediments for over 40,000 years.

    “Using the ancient trees we could measure, and date, the spike in atmospheric radiocarbon levels caused by the collapse of Earth’s magnetic field.”

    While scientists already knew the magnetic poles temporarily flipped around 41-42,000 years ago (known as the Laschamps Excursion), they didn’t know exactly how it impacted life on Earth – if at all.

    But the researchers were able to create a detailed timescale of how Earth’s atmosphere changed over this time by analysing rings on the ancient kauri trees.

    “The kauri trees are like the Rosetta Stone, helping us tie together records of environmental change in caves, ice cores and peat bogs around the world,” says co-lead Professor Alan Cooper, Honorary Researcher at the South Australian Museum.

    The researchers compared the newly-created timescale with records from sites across the Pacific and used it in global climate modelling, finding that the growth of ice sheets and glaciers over North America and large shifts in major wind belts and tropical storm systems could be traced back to the Adams Event.

    One of their first clues was that megafauna across mainland Australia and Tasmania went through simultaneous extinctions 42,000 years ago.

    “This had never seemed right, because it was long after Aboriginal people arrived, but around the same time that the Australian environment shifted to the current arid state,” says Prof. Cooper.

    The paper suggests that the Adams Event could explain a lot of other evolutionary mysteries, like the extinction of Neandertals and the sudden widespread appearance of figurative art in caves around the world.

    “It’s the most surprising and important discovery I’ve ever been involved in,” says Prof. Cooper.


    “Paleopocalypse!”
    Watch as Stephen Fry brings to life the story of the ‘Adams event’. Credit: UNSW Sydney.

    The perfect (cosmic) storm

    The magnetic north pole – that is, the direction a compass needle points to – doesn’t have a fixed location. It usually wobbles close to the North Pole (the northern-most point of Earth’s axis) over time due to dynamic movements within the Earth’s core, just like the magnetic south pole.

    Sometimes, for reasons that aren’t clear, the magnetic poles’ movements can be more drastic. Around 41,000-42,000 years ago they swapped places entirely.

    “The Laschamps Excursion was the last time the magnetic poles flipped,” says Prof. Turney. “They swapped places for about 800 years before changing their minds and swapping back again.”

    Until now, scientific research has focused on changes that happened while the magnetic poles were reversed, when the magnetic field was weakened to about 28 per cent of its present-day strength.

    But according to the team’s findings, the most dramatic part was the lead-up to the reversal, when the poles were migrating across the Earth.

    “Earth’s magnetic field dropped to only 0-6 per cent strength during the Adams Event,” says Prof. Turney.

    “We essentially had no magnetic field at all – our cosmic radiation shield was totally gone.”

    During the magnetic field breakdown, the Sun experienced several Grand Solar Minima (GSM), long-term periods of quiet solar activity.

    Even though a GSM means less activity on the Sun’s surface, the weakening of its magnetic field can mean more space weather – like solar flares and galactic cosmic rays – could head Earth’s way.

    “Unfiltered radiation from space ripped apart air particles in Earth’s atmosphere, separating electrons and emitting light – a process called ionisation,” says Prof. Turney.

    “The ionised air ‘fried’ the Ozone layer, triggering a ripple of climate change across the globe.”

    3
    From auroras to lightning storms, the sky would have put on quite a show during the Adams Event. Credit: Unsplash.
    Into the caves

    Dazzling light shows would have been frequent in the sky during the Adams Event.

    Aurora borealis and aurora australis, also known as the northern and southern lights, are caused by solar winds hitting the Earth’s atmosphere.

    Usually confined to the polar northern and southern parts of the globe, the colourful sights would have been widespread during the breakdown of Earth’s magnetic field.

    “Early humans around the world would have seen amazing auroras, shimmering veils and sheets across the sky,” says Prof. Cooper.

    Ionised air – which is a great conductor for electricity – would have also increased the frequency of electrical storms.

    “It must have seemed like the end of days,” says Prof. Cooper.

    The researchers theorise that the dramatic environmental changes may have caused early humans to seek more shelter. This could explain the sudden appearance of cave art around the world roughly 42,000 years ago.

    “We think that the sharp increases in UV levels, particularly during solar flares, would suddenly make caves very valuable shelters,” says Prof. Cooper. “The common cave art motif of red ochre handprints may signal it was being used as sunscreen, a technique still used today by some groups.

    “The amazing images created in the caves during this time have been preserved, while other art out in open areas has since eroded, making it appear that art suddenly starts 42,000 years ago.”

    4
    The centre of this cave art from El Castillo Cave in Spain is believed to be almost 42,000 years old – the same age as the Adams Event. Credit: Paul Pettitt, courtesy Gobierno de Cantabria.

    Uncovering ancient clues

    These findings come two years after a particularly important ancient kauri tree was uncovered at Ngāwhā, Northland.

    The massive tree – with a trunk spanning over two and a half metres – was alive during the Laschamps.

    “Like other entombed kauri logs, the wood of the Ngāwhā tree is so well preserved that the bark is still attached,” says UNSW’s Dr Jonathan Palmer, a specialist in dating tree-rings (dendrochronology). Dr Palmer studied cross sections of the trees at UNSW Science’s Chronos 14Carbon-Cycle Facility.

    Using radiocarbon dating – a technique to date ancient relics or events – the team tracked the changes in radiocarbon levels during the magnetic pole reversal. This data was charted alongside the trees’ annual growth rings, which acts as an accurate, natural timestamp.

    The new timescale helped reveal the picture of this dramatic period in Earth’s history. The team were able to reconstruct the chain of environmental and extinction events using climate modelling.

    “The more we looked at the data, the more everything pointed to 42,” says Prof. Turney. “It was uncanny.

    “Douglas Adams was clearly on to something, after all.”


    Ancient trees show turning point in Earth history 42,000yr ago.
    The ancient kauri trees were key to the findings, explain Prof. Chris Turney and Prof. Alan Cooper. Credit: UNSW Sydney.

    An accelerant like no other

    While the magnetic poles often wander, some scientists are concerned about the current rapid movement of the north magnetic pole across the Northern Hemisphere.

    “This speed – alongside the weakening of Earth’s magnetic field by around nine per cent in the past 170 years – could indicate an upcoming reversal,” says Prof. Cooper.

    “If a similar event happened today, the consequences would be huge for modern society. Incoming cosmic radiation would destroy our electric power grids and satellite networks.”

    Prof. Turney says the human-induced climate crisis is catastrophic enough without throwing major solar changes or a pole reversal in the mix.

    “Our atmosphere is already filled with carbon at levels never seen by humanity before,” he says. “A magnetic pole reversal or extreme change in Sun activity would be unprecedented climate change accelerants.

    “We urgently need to get carbon emissions down before such a random event happens again.”

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    U NSW Campus

    Welcome to The University of New South Wales(AU), one of Australia’s leading research and teaching universities. At UNSW, we take pride in the broad range and high quality of our teaching programs. Our teaching gains strength and currency from our research activities, strong industry links and our international nature; UNSW has a strong regional and global engagement.

    In developing new ideas and promoting lasting knowledge we are creating an academic environment where outstanding students and scholars from around the world can be inspired to excel in their programs of study and research. Partnerships with both local and global communities allow UNSW to share knowledge, debate and research outcomes. UNSW’s public events include concert performances, open days and public forums on issues such as the environment, healthcare and global politics. We encourage you to explore the UNSW website so you can find out more about what we do.

     
  • richardmitnick 2:36 pm on December 30, 2020 Permalink | Reply
    Tags: "Largest study of Asia's rivers unearths 800 years of paleoclimate patterns", , Monsoon Asia Drought Atlas (MADA), Paleoclimatology, Singapore University of Technology and Design [新加坡科技设计大学] (SG)   

    From Singapore University of Technology and Design [新加坡科技设计大学] (SG) via phys.org: “Largest study of Asia’s rivers unearths 800 years of paleoclimate patterns” 

    From Singapore University of Technology and Design [新加坡科技设计大学] (SG)

    via


    From phys.org

    December 30, 2020

    1
    The Mekong from Phou si. Credit: Wikipedia.

    813 years of annual river discharge at 62 stations, 41 rivers in 16 countries, from 1200 to 2012. That is what researchers at the Singapore University of Technology and Design (SUTD) produced after two years of research in order to better understand past climate patterns of the Asian Monsoon region.

    3
    Map of the Asian Monsoon region; river basins involved in this study are highlighted by subregion, rivers belonging to the world’s 30 biggest are shown with names indicated in blue.
    Credit: SUTD.

    4
    This “heat map” shows the reconstructed history of 62 river reaches (each row) over 812 years (each column). The stations are arranged approximately north to south (top down on y?axis) and divided into five regions as delineated in Figure 1: CA (Central Asia), EA (East Asia), WA (West Asia), CN (eastern China), SEA (Southeast Asia), and SA (South Asia).
    Credit: SUTD.

    3
    Map showing the network of tree-ring chronologies in ‘MonsoonAsia’ that we now have access to. The solid blue dots are LDEO chronologies and the solid red triangles are non-LDEO chronologies. The “additional” chronologies are sites that will be available to us, but for which we do not have specific map coordinates for plotting at this time. The thick gray arrows signify the coupled nature of the analyses that we propose to conduct.

    Home to many populous river basins, including ten of the world’s biggest rivers, the Asian Monsoon region provides water, energy, and food for more than three billion people. This makes it crucial for us to understand past climate patterns so that we can better predict long term changes in the water cycle and the impact they will have on the water supply.

    To reconstruct histories of river discharge, the researchers relied on tree rings. An earlier study by Cook et al. (2010) developed an extensive network of tree ring data sites in Asia and created a paleodrought record called the Monsoon Asia Drought Atlas (MADA).

    4
    An updated version of the Monsoon Asia Drought Atlas (MADA e Cook et al., 2010: http://iridl.ldeo.columbia.edu/SOURCES/.LDEO/.TRL/.MADA/.pdsi/) grid mesh with locations of its underlying tree-ring.

    SUTD researchers used the MADA as an input for their river discharge model.

    They developed an innovative procedure to select the most relevant subset of the MADA for each river based on hydroclimatic similarity. This procedure allowed the model to extract the most important climate signals that influence river discharge from the underlying tree ring data.

    “Our results reveal that rivers in Asia behave in a coherent pattern. Large droughts and major pluvial periods have often occurred simultaneously in adjacent or nearby basins. Sometimes, droughts stretched as far as from the Godavari in India to the Mekong in Southeast Asia. This has important implications for water management, especially when a country’s economy depends on multiple river basins, like in the case of Thailand,” explained first author Nguyen Tan Thai Hung, a Ph.D. student from SUTD.

    Using modern measurements, it has been known that the behavior of Asian rivers is influenced by the oceans. For instance, if the Pacific Ocean becomes warmer in its tropical region in an El Nino event, this will alter atmospheric circulations and likely cause droughts in South and Southeast Asian rivers. However, the SUTD study revealed that this ocean-river connection is not constant over time. The researchers found that rivers in Asia were much less influenced by the oceans in the first half of the 20th century compared to the 50 years before and 50 years after that period.

    “This research is of great importance to policy makers; we need to know where and why river discharge changed during the past millennium to make big decisions on water-dependent infrastructure. One such example is the development of the ASEAN Power Grid, conceived to interconnect a system of hydropower, thermoelectric, and renewable energy plants across all ASEAN countries. Our records show that ‘mega-droughts’ have hit multiple power production sites simultaneously, so we can now use this information to design a grid that is less vulnerable during extreme events,” said principal investigator Associate Professor Stefano Galelli from SUTD.

    More information: Hung T. T. Nguyen et al, Coherent Streamflow Variability in Monsoon Asia Over the Past Eight Centuries—Links to Oceanic Drivers, Water Resources Research (2020).

    See the full article here.

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Mission

    The Singapore University of Technology and Design [新加坡科技设计大学] (SG) is established to advance knowledge and nurture technically-grounded leaders and innovators to serve societal needs, with a focus on Design, through an integrated multi-disciplinary curriculum and multi-disciplinary research.

    Technology and design always have been and always will be essential for society’s prosperity and well-being.

    Embracing this tenet as a call to action, SUTD will be a leading research-intensive global university focused on technology and all elements of technology-based design.

    It will educate technically-grounded leaders who are steeped in the fundamentals of mathematics, science, and technology; are creative and entrepreneurial; have broad perspectives informed by the humanities, arts and social sciences; and are engaged with the world.

    It will embrace the best of the East and West and drive knowledge creation and innovation, as well as innovative curriculum and teaching approaches.

    Its faculty, students and staff will have

    far-reaching aspirations to create a better world by design,
    the confidence and courage to try new ideas and approaches,
    a questioning spirit fueled by the thrill of multi-disciplinary learning and doing, and
    life-long competencies, especially the ability and appetite to learn and innovate.

    By excelling in all these dimensions, SUTD will be viewed as the foremost university in the world for technology and design education and research.

     
  • richardmitnick 12:06 pm on November 12, 2020 Permalink | Reply
    Tags: "Past is Key to Predicting Future Climate Scientists Say", , , Paleoclimatology,   

    From University of Arizona: “Past is Key to Predicting Future Climate, Scientists Say” 

    From University of Arizona

    Nov. 5, 2020
    Daniel Stolte

    In a review paper published in the journal Science, a group of climate experts makes the case for including paleoclimate data in the development of climate models. Such models are used globally to assess the impacts of human-caused greenhouse gas emissions, predict scenarios for future climate and propose strategies for mitigation.

    1
    Rising sea levels are but one of the projections of future climate change exacerbated by fossil fuel burning. Credit: Pete Linforth/Pixabay.

    An international team of climate scientists suggests that research centers around the world using numerical models to predict future climate change should include simulations of past climates in their evaluations and statements of their model performance.

    “We urge the climate model developer community to pay attention to the past and actively involve it in predicting the future,” said Jessica Tierney, an associate professor in the University of Arizona’s Department of Geosciences and lead author of a new research review paper in the journal Science. “If your model can simulate past climates accurately, it likely will do a much better job at getting future scenarios right.”

    As more and better information becomes available about climates in Earth’s distant history – reaching back many millions of years before humans existed – past climates become increasingly relevant for improving scientists’ understanding of how key elements of the climate system are affected by greenhouse gas levels, according to the Science paper’s authors. Unlike historic climate records, which typically only go back a century or two – a mere blink of an eye in the planet’s climate history – paleoclimates cover a vastly broader range of climatic conditions that can inform climate models in ways historical data cannot. These periods in Earth’s past span a large range of temperatures, precipitation patterns and ice sheet distribution.

    “Past climates should be used to evaluate and fine-tune climate models,” Tierney said. “Looking to the past to inform the future could help narrow uncertainties surrounding projections of changes in temperature, ice sheets and the water cycle.”

    2
    Past carbon dioxide concentrations (left) compared to possible future emissions scenarios (right). The rate of current emissions is much faster – occurring over decades – unlike geological changes, which occur over millions of years. If emissions continue unabated, carbon dioxide levels by the year 2300 could meet or exceed values associated with past warm climates, such as the Cretaceous period 100 million years ago or the Eocene epoch 50 million years ago. Credit: Jessica Tierney/University of Arizona.

    Typically, climate scientists evaluate their models with data from historical weather records, such as satellite measurements, sea surface temperatures, wind speeds, cloud cover and other parameters. The model’s algorithms are then adjusted and tuned until their predictions mesh with the observed climate records. If a computer simulation produces a historically accurate climate based on the observations made during that time, it is considered fit to predict future climate with reasonable accuracy.

    “We find that many models perform very well with historic climates, but not so well with climates from the Earth’s geological past,” Tierney said.

    One reason for the discrepancies are differences in how the models compute the effects of clouds, which is one of the great challenges in climate modeling, Tierney said. Such differences cause models to diverge from each other in terms of what climate scientists refer to as climate sensitivity – a measure of how strongly the Earth’s climate responds to a doubling of greenhouse gas emissions.

    Several of the latest generation models that are being used for the next report by the Intergovernmental Panel on Climate Change, or IPCC, have a higher climate sensitivity than previous iterations, Tierney explained.

    “This means that if you double carbon dioxide emissions, they produce more global warming than their previous counterparts, so the question is: How much confidence do we have in these very sensitive new models?”

    In between IPCC reports, which typically are released every eight years, climate models are being updated based on the latest research data.

    “Models become more complex and, in theory, they get better, but what does that mean?” Tierney said. “You want to know what happens in the future, so you want to be able to trust the model with regard to what happens in response to higher levels of carbon dioxide.”

    While there is no debate in the climate science community about human fossil fuel consumption pushing Earth toward a warmer state for which there is no historical precedent, different models generate varying predictions. Some forecast an increase as large as 6 degrees Celsius by the end of the century.

    Tierney said while Earth’s atmosphere has experienced carbon dioxide concentrations much higher than today’s level of about 400 parts per million, there is no time in the geological record that matches the speed at which humans are contributing to greenhouse gas emissions.

    In the paper, the authors applied climate models to several known past climate extremes from the geological record. The most recent warm climate that may offer a glimpse into the future occurred about 50 million years ago during the Eocene epoch, Tierney said. Global carbon dioxide was at 1,000 parts per million at that time, and there were no large ice sheets.

    “If we don’t cut back emissions, we are headed for Eocene-like CO2 levels by 2100,” Tierney said.

    The paper’s authors discuss climate changes all the way back to the Cretaceous period about 90 million years ago, when dinosaurs still roamed Earth. That period shows that the climate can get even warmer – a scenario that Tierney described as “even scarier,” with carbon dioxide levels up to 2,000 parts per million and the oceans as warm as a bathtub.

    “The key is CO2,” Tierney said. “Whenever we see evidence of warm climate in the geologic record, CO2 is high as well.”

    Some models are much better than others at producing the climates seen in the geologic record, which underscores the need to test climate models against paleoclimates, the authors said. In particular, past warm climates such as the Eocene highlight the role that clouds play in contributing to warmer temperatures under increased carbon dioxide levels.

    “We urge the climate community to test models on paleoclimates early on, while the models are being developed, rather than afterwards, which tends to be the current practice,” Tierney said. “Seemingly small things like clouds affect the Earth’s energy balance in major ways and can affect the temperatures your model produces for the year 2100.”

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    The University of Arizona (UA) is a place without limits-where teaching, research, service and innovation merge to improve lives in Arizona and beyond. We aren’t afraid to ask big questions, and find even better answers.

    In 1885, establishing Arizona’s first university in the middle of the Sonoran Desert was a bold move. But our founders were fearless, and we have never lost that spirit. To this day, we’re revolutionizing the fields of space sciences, optics, biosciences, medicine, arts and humanities, business, technology transfer and many others. Since it was founded, the UA has grown to cover more than 380 acres in central Tucson, a rich breeding ground for discovery.

    U Arizona mirror lab-Where else in the world can you find an astronomical observatory mirror lab under a football stadium?

    University of Arizona’s Biosphere 2, located in the Sonoran desert. An entire ecosystem under a glass dome? Visit our campus, just once, and you’ll quickly understand why the UA is a university unlike any other.

     
  • richardmitnick 2:15 pm on September 2, 2020 Permalink | Reply
    Tags: "New mathematical method shows how climate change led to the fall of an ancient civilization", Measuring the presence of a particular isotope in stalagmites from a cave in South Asia scientists were able to develop a record of monsoon rainfall in the region for the past 5700 years., Paleoclimatology, , Settlements of the Indus Valley Civilization during different phases of its evolution.   

    From Rochester Institute of Technology: “New mathematical method shows how climate change led to the fall of an ancient civilization” 

    From Rochester Institute of Technology

    September 2, 2020
    Luke Auburn
    luke.auburn@rit.edu

    Chaos paper by RIT Assistant Professor Nishant Malik applies method to Indus Valley Civilization.

    1
    This figure shows the settlements of the Indus Valley Civilization during different phases of its evolution. RIT Assistant Professor Nishant Malik developed a mathematical method that shows climate change likely caused the rise and fall of the ancient civilization.

    A Rochester Institute of Technology researcher developed a mathematical method that shows climate change likely caused the rise and fall of an ancient civilization. In an article recently featured in the journal Chaos: An Interdisciplinary Journal of Nonlinear Science, Nishant Malik, assistant professor in RIT’s School of Mathematical Sciences, outlined the new technique he developed and showed how shifting monsoon patterns led to the demise of the Indus Valley Civilization, a Bronze Age civilization contemporary to Mesopotamia and ancient Egypt.

    Malik developed a method to study paleoclimate time series, sets of data that tell us about past climates using indirect observations. For example, by measuring the presence of a particular isotope in stalagmites from a cave in South Asia, scientists were able to develop a record of monsoon rainfall in the region for the past 5,700 years. But as Malik notes, studying paleoclimate time series poses several problems that make it challenging to analyze them with mathematical tools typically used to understand climate.

    “Usually the data we get when analyzing paleoclimate is a short time series with noise and uncertainty in it,” said Malik. “As far as mathematics and climate is concerned, the tool we use very often in understanding climate and weather is dynamical systems. But dynamical systems theory is harder to apply to paleoclimate data. This new method can find transitions in the most challenging time series, including paleoclimate, which are short, have some amount of uncertainty and have noise in them.”

    There are several theories about why the Indus Valley Civilization declined—including invasion by nomadic Indo-Aryans and earthquakes—but climate change appears to be the most likely scenario. But until Malik applied his hybrid approach— rooted in dynamical systems but also drawing on methods from the fields of machine learning and information theory—there was no mathematical proof. His analysis showed there was a major shift in monsoon patterns just before the dawn of this civilization and that the pattern reversed course right before it declined, indicating it was in fact climate change that caused the fall.

    Malik said he hopes the method will allow scientists to develop more automated methods of finding transitions in paleoclimate data and leads to additional important historical discoveries.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Rochester Institute of Technology (RIT) is a private doctoral university within the town of Henrietta in the Rochester, New York metropolitan area.

    RIT is composed of nine academic colleges, including National Technical Institute for the Deaf. The Institute is one of only a small number of engineering institutes in the State of New York, including New York Institute of Technology, SUNY Polytechnic Institute, and Rensselaer Polytechnic Institute. It is most widely known for its fine arts, computing, engineering, and imaging science programs; several fine arts programs routinely rank in the national “Top 10” according to US News & World Report.

    The Institute as it is known today began as a result of an 1891 merger between Rochester Athenæum, a literary society founded in 1829 by Colonel Nathaniel Rochester and associates, and Mechanics Institute, a Rochester institute of practical technical training for local residents founded in 1885 by a consortium of local businessmen including Captain Henry Lomb, co-founder of Bausch & Lomb. The name of the merged institution at the time was called Rochester Athenæum and Mechanics Institute (RAMI). In 1944, the school changed its name to Rochester Institute of Technology and it became a full-fledged research university.

     
  • richardmitnick 1:34 pm on August 28, 2020 Permalink | Reply
    Tags: "Understand the past to understand the future: Climate science at Princeton", , Because they represent actual pieces of the past instead of fossilized proxies ice cores are considered the “gold standard” for paleoclimate studies., Both on the front end and the back end of building models you need to have very strong involvement of observations., , Geosciences at Princeton, Ice core research is emblematic of Princeton’s approach to climate science across the board over the last half-century., If you want to study the natural world you’re operating at the intersection between physics chemistry biology and geoscience., , Paleoclimatology, , SOCCOM-Southern Ocean Carbon and Climate Observations and Modeling project., The biogeochemistry of the ocean becomes critical to understanding the biogeochemistry of the globe., The combination of theory and observation has been critical., The ice cores in Guyot Hall include many samples in addition to the multi-million-year-old record setter., The international observational program known as TOGA or Tropical Ocean Global Atmosphere.   

    From Princeton University: “Understand the past to understand the future: Climate science at Princeton” 

    Princeton University
    From Princeton University

    Aug. 28, 2020
    Liz Fuller-Wright

    1
    This animation shows the snow and ice melt during a record heat wave in February 2020 on Eagle Island, near the northern tip of the Antarctic Peninsula. NASA Earth Observatory images by Joshua Stevens, using Landsat data from the U.S. Geological Survey and GEOS-5 data from the Global Modeling and Assimilation Office at NASA GSFC. Credit: Matilda Luk, Office of Communications.

    NASA/Landsat 8

    3
    GEOS-5. NOAA.

    Princeton’s vital research across the spectrum of environmental issues is today and will continue to be pivotal to solving some of humanity’s toughest problems. Our impact is built on a long, deep, broad legacy of personal commitment, intellectual leadership, perseverance and innovation. This article is part of a series to present the sweep of Princeton’s environmental excellence over the past half-century.

    Enter the front doors of Guyot Hall, the 111-year-old building that houses the Department of Geosciences at Princeton. Pass the glass specimen cases and the lobby’s iconic model of planet Earth and head to room M56. There, beyond the rows of heavy-duty snow boots and bulky parkas, stands a walk-in freezer storing some of the rarest artifacts of modern climate science: ancient ice cores harvested from Antarctica. At more than 2 million years old, these are the oldest ice cores ever collected.

    “Over the last 60-plus years, ice cores have produced the best evidence we have that carbon dioxide is linked to the Earth’s climate” said John Higgins, project leader for the group that recovered the ice in 2019 and an associate professor of geosciences.

    “When we had an ice age, atmospheric carbon dioxide was significantly lower than it is today, and every time we didn’t have an ice age, atmospheric carbon dioxide was high — all that is known from ice cores,” he said. “My team is contributing to that puzzle by extending that record further back in time.”

    The ice core research is emblematic of Princeton’s approach to climate science across the board over the last half-century, said Bess Ward, the William J. Sinclair Professor of Geosciences and the Princeton Environmental Institute (PEI) and chair of the geosciences department. “There’s a saying that geoscientists believe firmly, which is, ‘The key to the present is the past, and the key to the future is the present,’” she said. “If we can understand the past, we can understand the future.”

    And for more than 50 years, Princeton researchers have been doing just that. They’ve pushed back the boundaries of climate knowledge across a wide range of lynchpin issues. Princeton climate modelers, for example, developed the world’s first coupled ocean-atmosphere model, using physical laws and present Earth conditions to develop mathematical algorithms that can predict how Earth’s climate will respond to different conditions in the future — and to understand what drove climate changes in the past. Funneling data into the models are Princeton oceanographers and field geologists who have fanned out across the globe to understand what oceans and ecosystems are doing today. And paleoclimatologists have been using fossils, pollen records, ice cores and other tools to study how the global climate has already changed in the planet’s long history.

    Ground-truthing the theory

    The combination of theory and observation has been critical. The importance of “boots on the ground, boats in the water” can’t be overstated, said Gabriel Vecchi, a leading climate modeler as well as a professor of geosciences and PEI. Modern climate modelers such as himself benefit from the direct observations gathered by the geologists and oceanographers working “just down the hall,” he said.

    “We can have great theories that make very nice predictions, but we need to test those predictions, and you only test those predictions with observations,” Vecchi said. “At the same time, the fundamental processes that we put into our models have to be developed from some sort of empirical base. So, both on the front end and the back end of building models, you need to have very strong involvement of observations.”

    One Princeton scholar deeply involved in both theory and observation is Samuel G.H. “George” Philander, best known for his work on tropical oceans. His discovery of the recurring La Niña weather pattern and his seminal work on the related El Niño phenomenon dramatically improved scientists’ understanding of those enormous climate fluctuations. That knowledge, in turn, helps governmental and economic planners prepare for their effects.

    Philander, now the Knox Taylor Professor of Geosciences, Emeritus, also helped organize a decade-long (1985-1994) international observational program known as TOGA, or Tropical Ocean Global Atmosphere. TOGA was designed to test the emerging theory of what is called “the coupled ocean-atmosphere system” in the tropics and paved the way for future ocean observation systems. It also led to improved simulations in global climate models.

    “George was fundamental in developing our basic understanding of the El Niño phenomenon, which is the largest year-to-year fluctuation in the climate system,” said Vecchi. For hundreds of years, El Niño had been known as an ocean phenomenon that warmed the seas off the coast of Peru and shifted rainfall and other climate patterns. Philander helped shift scientists’ understanding of it from a purely oceanic event to one that was dependent on the coupled ocean-atmosphere system — the planet’s interconnected and interdependent water and air.

    “That was a fundamental shift in the way that we looked at these fluids,” said Vecchi. “We realized that the ocean and atmosphere had to be understood together.”

    Also critical to that understanding was Syukuro “Suki” Manabe, one of the founders of modern climate modeling, who created the first coupled ocean-atmosphere computer model in 1969 with his colleague Kirk Bryan, an oceanographer. Both Manabe and Bryan were lecturers with the rank of professor at Princeton while also holding positions at the Geophysical and Fluid Dynamics Laboratory (GFDL) on Princeton’s Forrestal Campus. “An improved version of that coupled model has become indispensable not only for predicting the climate change of the industrial present but also for exploring the climate of the geological past,” Manabe said.

    By changing the conditions (i.e., distribution of continent, concentration of carbon dioxide) modelers can recreate past eras as they predict the future, Manabe explained. Testing climate models against paleoclimates — ancient climates — is one of the key ways that climate modelers test their algorithms.

    Frozen in time

    The ice cores in Guyot Hall include many samples in addition to the multi-million-year-old record setter. The long, narrow cylinders of glacial ice, painstakingly gathered over the past half-century, are speckled with tiny bubbles of air that are trapped in the ice like dragonflies in amber. How do these trapped air bubbles form? As snow falls, it creates air pockets, and as that snow compacts into ice, those pockets become time capsules holding ancient air, whatever gases were present in the atmosphere, and even microscopic particles of pollen or volcanic ash — all clues to the past climate.

    “For somebody who’s trying to reconstruct what the environment was like in the past, you can’t ask for anything better than a sample of ancient air, or a sample of ancient water,” said Higgins, who keeps breaking his own records for the oldest ice samples ever found. “In addition to the trapped air, you also have the ice itself, which provides its own record of climate at the time.”

    Because they represent actual pieces of the past, instead of fossilized proxies, ice cores are considered the “gold standard” for paleoclimate studies, Higgins said. Climate scientists have built a record of the planet’s temperatures and carbon dioxide levels by measuring the gases and isotopes in these ancient samples. The continuous record goes back about 800,000 years before the present, and the older samples that Higgins has found provide snapshots of even earlier eras.

    Princeton has long been a leader in ice core research; Higgins came to the University to work with one of the founders of the field, Michael Bender, now an emeritus professor of geosciences. Bender is responsible for many of the innovations necessary to work with ancient ice, including a revolutionary approach to calculating the ice’s age by using the argon isotopes in the air bubbles.

    “In truth, Michael has played a central role in the development of nearly all of the current activities on ice core gases and almost singlehandedly trained the field’s most prominent researchers,” said his colleagues when Bender transferred to emeritus status in 2014. “We can say unequivocally that he has been at the forefront of this pioneering field,” Higgins agreed.

    In past decades, Bender was one of the scientists responsible for pushing the record back to 400,000 years, which included several ice age cycles. As Higgins and his team continued Bender’s work, they first extracted a 1-million-year old core in 2015 and then the 2+ million-year-old core in 2019.

    The team is returning next season to look for even older samples. The goal is to find frozen bubbles of ancient atmosphere from a time period more than 2.7 million years ago that was 1-2 degrees warmer than today — a period often cited by climate scientists as a likely analogue for Earth’s climate in the 21st century. “Ice of this vintage would provide researchers with the first direct evidence for atmospheric greenhouse gases at that time and an unprecedented glimpse of many important aspects of Earth’s climate system,” Higgins explained.

    “Reconstructing Earth’s climate in the past, studying climate change in the future — these are two complementary ways of getting at the same question,” Higgins said.

    The ocean’s role in climate

    Ice core bubbles can show carbon dioxide, methane and other greenhouse gases increasing during warm periods and dropping during ice ages, but they can’t say why it happened. Figuring that out involves examining the carbon cycle from a variety of angles.

    In Higgins’ view, “Understanding the carbon cycle involves all of our different gifts.” He cited the work of oceanographers Bess Ward and Daniel Sigman. Ward takes crews of students and other researchers to key locations around the world to investigate the global ocean’s nitrogen and carbon cycling. Sigman’s research group also makes new kinds of measurements in fossils from ocean sediment cores. The results reveal how past changes in ocean conditions have altered the storage of carbon dioxide in the ocean, changing atmospheric carbon dioxide levels and thus global climate.

    “Danny Sigman’s research has been at the forefront of understanding ancient oceans,” said Ward. “And by that, I mean, the circulation and the biological and chemical conditions of the oceans in the past. …Understanding the oceans of the past is the only way we can think to understand the oceans of the future. So if we understand how ocean circulation, for example, responded to changes in global temperature or distribution of temperature or distribution of ice, then we can have a good shot at forecasting what will happen when the ice caps melt.”

    To study the world’s oceans, past and present, Ward and Sigman rely on sophisticated shipboard instrumentation and retrieval tools that drop deep below the ocean surface, far below levels that can be reached by scuba divers.

    “The deep ocean is the ocean,” stressed Sigman, the Dusenbury Professor of Geological and Geophysical Sciences. Globally, the oceans have an average depth of about 3,657 meters (12,000 feet), while the “surface ocean” is generally defined as the top 100 meters (330 feet).

    “The surface ocean is the thin skin,” he said. “It is the interface with the atmosphere and the habitat for most ocean life. It’s critical — but the biggest part of the ocean’s volume is the deep ocean. So the question becomes, how rapidly can heat from global warming and carbon dioxide from fossil fuel burning make their way into the deep ocean?”

    Surveying the seas

    Ocean cruises led by Ward and colleagues are necessarily limited in space and time, but Princeton researchers have also been leaders in the evolving field of remote data gathering.

    The flotilla of observational floats in the TOGA program that George Philander helped organize, paved the way for the Southern Ocean Carbon and Climate Observations and Modeling project (SOCCOM), a multi-institutional program housed at Princeton and funded by the National Science Foundation. It uses more than 150 floating data collectors to determine how the Southern Ocean — the ocean encircling Antarctica — influences the world’s climate. The project is directed by Jorge Sarmiento, a biogeochemist and the George J. Magee Professor of Geoscience and Geological Engineering, Emeritus.

    In the 1980s, Sarmiento and GFDL scientist J.R. “Robbie” Toggweiler were one of three groups to simultaneously discover the importance of the Southern Ocean in controlling the atmosphere’s carbon dioxide levels. Since that work, a lack of data has hampered understanding of this critical but remote region. The SOCCOM project is a “game-changer,” said Sigman, acquiring data even through the harshest of winter conditions. Sarmiento’s discoveries about the Southern Ocean have inspired Higgins and Sigman, who have looked to the Southern Ocean in the effort to explain past changes in atmospheric carbon dioxide and climate.

    Princeton’s deep strength in ocean studies is no accident, said Ward. “Climate, as a subset of environmental research, is a motivating factor for all of the research that we do,” she said. “The reason we’re not already at 4 degrees Celsius of global warming — or more — is because a substantial portion of the carbon dioxide that humans have emitted is now in the ocean. And so the biogeochemistry of the ocean becomes critical to understanding the biogeochemistry of the globe.”

    For decades, Sarmiento was one of the only biogeochemists in the world — “I was kind of an orphan,” he joked — until more and more scientists came to see how interconnected the natural sciences are.

    “If you want to study the natural world, you’re operating at the intersection between physics, chemistry, biology and geoscience,” said Sigman. “That’s what’s behind the snarl of a name: biogeochemistry. What attracted me to this work in the first place was that I didn’t want to leave any of these disciplines behind — and I haven’t had to.”

    See the full article here .

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  • richardmitnick 9:50 am on August 24, 2020 Permalink | Reply
    Tags: "Southeast Asian megadrought dating back 5000 years discovered in Laos cave", , Evidence for the megadrought came from Laos’ Luang Prabang Province where White has worked since 2001., Joyce White, Much like tree rings stalagmites have rings that contain datable signs of changing climate., Paleoclimatology, ,   

    From Penn Today: Women in STEM-“Southeast Asian megadrought dating back 5,000 years discovered in Laos cave” Joyce White 


    From Penn Today

    August 21, 2020
    Michele W. Berger

    In a Q&A, Penn archaeologist Joyce White discusses the partnership with paleoclimatologists that led to the finding, plus possible implications of such a dramatic climate change for societies at that time.

    1
    Penn archaeologist Joyce White (center) has been working in Laos since 2001 with teams like the one shown here. Discovering evidence of a 1,000-year drought in a Laos cave was unexpected, she says, but does answer some questions about the Middle Holocene, a period she’d previously described as the “missing millennia.” (Pre-pandemic image: Courtesy of Joyce White.)

    Southeast Asia typically evokes rich and wet tropical forests. So, the discovery of a drought more than 1,000 years long beginning about 5,000 years ago was an unexpected outcome from research started by the Penn Museum’s Joyce White nearly two decades ago. She and colleagues from the University of California, Irvine; William Paterson University; the University of Quebec; and more published these findings in the journal Nature Communications.

    Evidence for the megadrought came from Laos’ Luang Prabang Province, where White has worked since 2001. A Henry Luce Foundation grant enabled the research program to expand starting in 2008, and a paleoclimate team that included William Paterson’s Michael Griffiths and Kathleen Johnson of UCI, co-lead authors on the latest paper, joined in 2010. Some of their work included collecting stalagmite samples from the Tham Doun Mai cave along the Ou River.

    Much like tree rings, stalagmites have rings that contain datable signs of changing climate. As rainwater drips through cracks in a cave’s roof, it interacts with a mineral called calcite to form stalactites on the cave’s ceiling. As that water-mineral mixture drips from the stalactite, stalagmites form on the floor below, building over time, layer by layer.

    “From those rings, we can interpret the occurrence of various climate events,” says White, who directs the Penn Museum’s Middle Mekong Archaeological Project and is an adjunct professor in Penn’s Department of Anthropology. “In this case, two of the stalagmites stopped growing for several hundred years, then started to grow again.” Chemical analyses confirmed that a prolonged drought lasting more than 1,000 years caused the cessation.

    When combined with climate modeling, the cave evidence seems connected to changes in vegetation and dust in northern Africa that happened around the same time—right around when the Sahara transitioned from forest to desert. The modeling also showed how such changes in northern Africa could affect rainfall across Southeast Asia. Penn Today talked with White about what the discovery means, plus the work that led to it.

    2
    Rock shelters in Laos near the Tham Doun Mai cave where researchers found evidence of the 1,000-year megadrought. (Pre-pandemic image courtesy of Joyce White)

    What’s the main finding of this research?

    There was this absolutely huge drought that lasted for more than 1,000 years that occurred in the Middle Holocene. That’s amazing in and of itself and wasn’t really anticipated by other research. This is outstanding evidence for the type of climate change that must have affected societies, what plants were available, what animals were available. All of biotic life had to adjust to this very different climate. From an archaeological point of view, this really is a game changer in how we try to understand and reconstruct this period.

    When you refer to the Middle Holocene, what do you mean?

    The Holocene in general is commonly considered to begin about 11,000 years ago, and the Middle Holocene is from about 6,000 to 4,000 years ago.

    Before this finding, what did we know about the Holocene?

    We understood pretty well what was going on in the Early Holocene, essentially hunting and gathering. We also knew that the Late Holocene was an agrarian period. The link between the two was still a mystery, mysterious partly because there is a Middle Holocene gap in the archaeological record in interior Southeast Asia, what I’d been calling the missing millennia.

    There’s a mountain range between Vietnam and the Mekong Valley, where Laos is. On the Vietnam side, there are many Middle Holocene sites, but I wanted to find those on the west side, on the Laos side in the Mekong Valley. Archaeology is very much the tortoise and not the hare; you can’t necessarily go into a region and know you’re going to find evidence for whatever you’re hypothesizing. You record whatever you find, and that takes energy and time. We knew the Middle Holocene had to be there somewhere. I figured we just didn’t quite understand the landscape yet. This was before we knew about this drought.

    How did this archaeological work in Laos begin?

    Like many countries in Southeast Asia, Laos was not accessible to research until the ’90s. However, Thailand has been an area of archaeological study since the 1960s, and Penn was one of a handful of pioneering universities that undertook fieldwork there. The site we’re most famous for is Ban Chiang, now a UNESCO World Heritage Site, and research related to that site is one of my main research endeavors.

    In the late 1990s, the director of the Penn Museum urged me to set up a project in Laos. In those days, that wasn’t an easy thing to do. When I got there, I was assigned a counterpart. We rented a truck and drove around first near Vientiane, the capital, followed by a brief trip to Luang Prabang, a former royal capital. In about two and a half days in Luang Prabang, I saw evidence of 10,000 years of human occupation, which is not an everyday occurrence for an archaeologist. It was mind-blowing.

    During that initial trip, you’ve said that you noticed Luang Prabang was located at the intersection of the Seuang, Khan, and Ou rivers, where they meet and flow into the Mekong. How did that guide your next steps?

    I decided I wanted to do a regional survey that looked at all three rivers, not just one, because you could pick the wrong one. We would use mobile GIS, which was cutting edge at that time, and have three separate teams exploring each river independently. Then we’d collate the data. I took another trip to get the Lao government to agree to my plan, and it took a year or two to raise money.

    In 2005, with grants from the National Science Foundation and the National Geographic Society, we conducted the first formal survey of the Middle Mekong Archaeological Project. Everything was joint teams; I wanted 50-50 Lao, non-Lao teams. In about three weeks, we found nearly 60 sites, which demonstrated that this was an archaeologically rich area. We found evidence of the Stone Age, ceramics of a wide variety, the kind of thing you can find on the surface of sites and in caves.

    We started test excavations of cave sites beginning in 2007. The research being published today is from 2010, the first season the paleoclimatologists joined us. They looked at many other sites, but that one on the Ou River and in the Tham Doun Mai cave was the outstanding one.

    How did the team unearth the megadrought?

    When rainwater from stalactites drips, stalagmites form beneath. Based on their growth and chemistry, the layers can be dated. For two of the stalactites, the dripping stopped, and preliminary data show it was for 1,000 to 2,000 years. That indicates that it wasn’t just a dry spell. It was massive.

    This type of complete change in climate has to have an impact on the biotic life, but we don’t really understand that in detail yet. That being said, I think this is going to change the conversation about that whole period across Eurasia and certainly Southeast Asia. The fact that there are profound climatic phenomena at a continental scale in the Holocene timeframe is quite new in scholarly conversations among archaeologists. This kind of research, when you combine archaeology, paleoclimatology, and modeling, will more effectively bring out this type of finding.

    What’s next for your work?

    With COVID, who knows when we can start fieldwork again. We didn’t finish our survey on the Ou River so I would like to do that. But to flesh out the human part of the story, we need to look at aspects of our excavated evidence, including shells we had collected from the four tested sites, which were different ranges of species. Once you know what the shell is adapted to, you can get human-scaled evidence for change of subsistence and environment. We made great headway this past January and we have other animal remains to study, too. You can get some nice tight data that inform much more on the human dimension in relationship to the massive climate shifts.

    See the full article here .

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  • richardmitnick 9:01 am on March 6, 2020 Permalink | Reply
    Tags: , , , , Paleoclimatology, Speleology-the study of caves   

    From Horizon The EU Research and Innovation Magazine: “Cave rock studies provide window into ancient civilisations” 

    1

    From Horizon The EU Research and Innovation Magazine

    05 March 2020
    Caleb Davies

    There is a certain romance to speleology, the study of caves, if you can see past the cold and the damp and the dark. Caves are ancient and often beautiful places. And they can be useful. Rock formations in caves, it turns out, hold within them chemical secrets that provide a window on both ancient civilisations and the climate of the future.

    1
    Speleothems, such as stalactites and stalagmites, may hold the secrets of why ancient civilisations collapsed. Image credit – Sebastian Breitenbach.

    Many people think of speleothems, or cave rocks, as being dull and brown. But they come in a wide palette of colours. ‘I was recently with a friend in an abandoned mine where there were some rocks that had a bluish, greenish sheen because they had a lot of copper in them,’ said Dr Sebastian Breitenbach. ‘It’s really rare to see that.’

    Think of a speleothem and you’re probably imagining stalactites and stalagmites. (To remember which is which, try thinking of stalactites having to hold on tight; they’re the ones that hang from the ceiling.) These rocks are formed as water drips into a cave and the dissolved carbonate it contains gradually precipitates out. You also get flowstones formed from underground streams and thin-walled tubes of rock known as ‘soda straws’.

    These rocks grow achingly slowly: a few tenths of a millimetre per year in the fastest cases. This means stalactites can be tens of thousands of years old. And because cave rock is laid down gradually by individual drops of water, it stores a record of their chemical composition.

    It turns out that some of these chemical signatures vary depending on the climate at the time. Take for instance the ratio of two isotopes of oxygen, oxygen-16 and oxygen-18. Rainwater contains a specific ratio of the two and so by grinding down samples from speleothems and analysing the isotope ratio at different points along the length of the rock, geochemists can get a hint of how rainy it was, or where the rain originated from when the rock formed. There are plenty of other proxies besides oxygen too.

    Ancient

    This record of ancient climate entombed in stone turns out to be useful in giving us a handle on what life was like for ancient civilisations. It can also tell us about periods such as the mysterious Bronze Age collapse.

    This was the 50-year period in which several major civilisations in the Mediterranean, including the Egyptian empire, the Mycenaeans and the Hittites, all collapsed about 3,000 years ago. Some reckon this might have been to do with a megadrought that hit the region. But this is a controversial idea and there are plenty of other theories. Some ancient texts pin the blame on invading hordes known as the ‘sea peoples’.

    ‘Turkey has been home to many important ancient human cultures, from some of the world’s earliest farming societies in the Palaeolithic to more modern societies like the Hittites, classical Greeks, Roman, Byzantine and Ottoman empires,’ said Dr Ezgi Unal-Imer at the Middle East Technical University in Ankara, Turkey. ‘We are sure that they must have been heavily influenced by (changing) environmental conditions.’

    That’s why she began the Speleotolia project, with the goal of collecting high resolution paleoclimate data from Turkey. She has been collecting samples from caves over the past few years including 10 stalagmites from western Turkey.

    Five of these cover the Holocene period and she has one sample that provides a continuous line of growth going back 1,825 years. ‘This covers almost the entire common era – it’s a really good sample,’ she said.

    She’s currently about halfway through drilling 420 samples, which will help her reconstruct the past climate conditions. Dr Unal-Imer is excited about what they’ll uncover. We just don’t know what we will find, she says.

    Rain

    One thing her project won’t do, however, is quantify how much rain fell in any given year in the past.

    At the moment, most speleothem data can only signal short-term climate trends, says Dr Breitenbach who is based at Northumbria University in Newcastle, UK. In other words, it can tell us a certain period was much rainier than the one before – but not how many millimetres of rain fell. Why so?

    Well, let’s take the ratio of oxygen isotopes in a rock again. In truth, though this is influenced by rainfall it is also nudged up and down by other factors like temperature, and the topography and humidity of the particular cave.

    2
    Organo-metallic molecules in cave rock may be able to tell scientists about historical temperatures. Image credit – Adam Hartland.

    The QUEST project that Breitenbach led is trying to change that uncertainty, using two strategies. The first involves detailed work on one of the Waitomo caves in New Zealand. The plan is to measure many proxies in parallel and see how they all vary over time. Variations in one proxy might be caused by several factors and it’s impossible to know how much each contributed. But look at the variations in 10 or 15 proxies in tandem and there should be only one hypothesis for how the rainfall has changed quantitatively, say, that fits all the facts. ‘Then it’s like an Agatha Christie crime novel,’ said Dr Breitenbach. ‘All the facts that we learned from the proxies must fit in the interpretation.’

    One minus to this strategy, however, is that it requires a detailed understanding of the cave where the speleothem samples were taken. This means the researchers would have to summon their inner detective afresh with nearly every rock sample.

    The second strategy is to discover new proxies that really are only impacted by one variable and so can provide quantitative data directly. Dr Adam Hartland at the University of Waikato in Hamilton, New Zealand has been leading this part of the work.

    Calibrate

    He’s discovered some molecules known as organo-metallic complexes for which it’s possible to quantify how they change in cave rocks in response to temperature in great detail. The trick will be to calibrate this proxy, so that we can say a measurement of a certain amount of the complex signifies a certain temperature. ‘We know how to do that – but we haven’t quite done it yet,’ said Dr Breitenbach.

    What does all this have to do with the future though? Well, harvesting information about the past is crucial for answering questions about what will happen to rainfall and temperature in the face of the climate emergency. Take the El Niño–Southern Oscillation (ENSO), a weather pattern that affects ocean temperatures and shifts rain around in the southern hemisphere with catastrophic effects on fishing and farming.

    At the moment, we have a poor grasp of how ENSO was affected by climate change in the past. But with speleothems, we can go back in time and look at a period that was particularly warm. ‘We can see how often there were El Niños, how strong were they, and where were their strongest impacts? Then we can use the past as a key to the future,’ said Dr Breitenbach.

    See the full article here .


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