From The Arizona State University
12.19.23
T.J. Triolo
Regents Professor Ying-Cheng Lai led development of a mathematical mechanism that provides insight about the rate and effects of climate change.
Ying-Cheng Lai, a Regents Professor of electrical engineering in the Ira A. Fulton Schools of Engineering at Arizona State University, led research for a paper published in the PNAS to calculate when “tipping points” of irreversible changes in systems happen. Photo courtesy of Francesco Ungaro/Pexels.
As humans continue to drive environmental damage through climate change, predicting points of no return becomes more crucial than ever. Worldwide, humanity and nature alike contend with increases in temperature, drought, wildfires, hurricanes, rising sea levels and more.
Ying-Cheng Lai, a Regents Professor of electrical engineering in the Ira A. Fulton Schools of Engineering at Arizona State University, leads projects investigating the impact of rate-induced tipping on the natural environment. Rate-induced tipping quantifies the rate at which a system changes to reach a tipping point, or the critical time at which major harm to the ecosystem occurs, such as the extinction of vital species.
Lai and his colleagues’ latest efforts analyzed the impact of rate-induced tipping on organisms that depend on one another for survival, such as the photosynthetic cells in a reef and the coral that depend on them. Using mathematical models, the researchers discovered that to avoid environmental catastrophes, a system would need to bring its rate of change as close to a halt as possible, rather than simply slowing it down.
Lai and his colleagues’ efforts earned their resulting paper a spot in the PNAS [below], the scientific journal of the National Academy of Sciences.
A new frontier for rate-induced tipping research
While research on tipping points is a well-established field, Lai and his colleagues — who for this project included Shirin Panahi, a Fulton Schools electrical engineering postdoctoral fellow; Younghae Do, a professor of mathematics at South Korea’s Kyungpook National University; and Alan Hastings, a distinguished professor emeritus specializing in theoretical ecology at the University of California-Davis — took a new approach to examining the progression of rates of a system’s states to find when a system will collapse.
They found that previous investigations in the field focused specifically on certain points in the phase space, which relies on spatial locations of system states, and their associated rates, rather than observing the full picture of all accessible points in the state space of the underlying system.
Lai and his team sought to find the probability of rate-induced tipping in the whole state space, then used the corresponding data to build a mathematical theory that could be applied generally to systems in the ecological and biological realms.
Evaluating environmental impact
An ecological example of the research’s applications is analyzing the effect of climate change-caused rates of environmental degradation on corals and their zooxanthellae, which are microscopic organisms that live in corals and provide them with food through photosynthesis.
As oceans warm due to absorbing more carbon from human-caused emissions, scientists can use the rate-induced tipping research to determine when the hotter water will cause irreversible damage to corals. An example of system-collapsing damage is severe bleaching, which happens when the zooxanthellae leave their coral hosts and put the corals in a vulnerable state.
Because corals support a variety of reef life, coral bleaching has large upstream impacts on ecosystems, including human populations whose food supply depends on fish that live in reefs.
“When the rate of parameter change exceeds some critical value, a system can collapse in the sense of massive extinction in relatively short time,” Lai says. “The main finding is that even a slow parameter change can suddenly lead to a system collapse with catastrophic consequences.”
Beyond climate change, the research can be applied to biological systems as well, such as estimating what rate of change results in failure of a cell to perform its genetically determined function.
Changing the course of future events
Ultimately, Lai wants to prepare humanity to avoid future disasters or mitigate their effects through his rate-induced tipping research. His future projects in the area aim to take his current knowledge further.
Lai plans to use his findings from the rate-induced tipping research to create machine learning models that can pinpoint systemic calamities for more specific applications. For example, he hopes to create a model to predict the potential collapse of the Atlantic Meridional Overturning Circulation, a current system transporting warm and cold water throughout the ocean that keeps the climate mild in Western Europe.
The currents’ movement is slowing as the oceans warm, and the machine learning model would build on Lai’s established research to determine when Western Europe should prepare for severe changes in the climate due to the currents’ decline.
As he sets out to understand and predict sudden systemic changes in nonlinear and complex dynamical systems and beyond, Lai is confident ASU serves as a great institution at which to conduct his research.
“This line of research is strongly interdisciplinary among applied mathematics, physics, engineering, ecology, scientific computing and machine learning,” he says. “ASU has provided a world-class interdisciplinary environment that greatly facilitated the research.”
Lai also emphasizes the importance of having his work published in PNAS.
“PNAS is a selective journal,” Lai says. “A paper published in PNAS will receive attention from the research community. It will also be helpful for the career development of my postdoctoral fellow and coauthor Shirin Panahi.”
Fig. 1.
Probability of R-tipping versus the time rate of parameter change for ten real-world mutualistic networks, together with the corresponding bipartite structure for each network. The dots are the probability calculated by simulating Eqs. 3a*, 3b*, and 4*, with an ensemble of random initial conditions. The solid curves are the analytic results from Eq. 1, with the two fitting parameters and given in Table 1*….
*Science paper reference.
See the science paper for further instructive material with images and tables.
See the full article here.
Comments are invited and will be appreciated, especially if the reader finds any errors which I can correct. Use “Reply” at the bottom of the post.
five-ways-keep-your-child-safe-school-shootings
Please help promote STEM in your local schools.
The Arizona State University Tempe Campus.
The Arizona State University is a public research university in the Phoenix metropolitan area. Founded in 1885 by the 13th Arizona Territorial Legislature, ASU is one of the largest public universities by enrollment in the U.S.
One of three universities governed by the Arizona Board of Regents, The Arizona State University is a member of the Universities Research Association and classified among “R1: Doctoral Universities – Very High Research Activity.” The Arizona State University has more than 150,000 students attending classes, with more than 38,000 students attending online, and over 90,000 undergraduates and more nearly 20,000 postgraduates across its five campuses and four regional learning centers throughout Arizona. The Arizona State University offers 350 degree options from its 17 colleges and more than 170 cross-discipline centers and institutes for undergraduates students, as well as more than 400 graduate degree and certificate programs. The Arizona State Sun Devils compete in 26 varsity-level sports in the NCAA Division I Pac-12 Conference and is home to over 1,100 registered student organizations.
The Arizona State University ‘s charter, approved by the board of regents in 2014, is based on the New American University model created by The Arizona State University President Michael M. Crow upon his appointment as the institution’s 16th president in 2002. It defines The Arizona State University as “a comprehensive public research university, measured not by whom it excludes, but rather by whom it includes and how they succeed; advancing research and discovery of public value; and assuming fundamental responsibility for the economic, social, cultural and overall health of the communities it serves.” The model is widely credited with boosting The Arizona State University ‘s acceptance rate and increasing class size.
The university’s faculty of more than 4,700 scholars has included Nobel laureates, Pulitzer Prize winners, MacArthur Fellows, and National Academy of Sciences members. Additionally, among the faculty are Fulbright Program American Scholars, National Endowment for the Humanities fellows, American Council of Learned Societies fellows, members of the Guggenheim Fellowship, members of the American Academy of Arts and Sciences, members of National Academy of Inventors, National Academy of Engineering members and National Academy of Medicine members. The National Academies has bestowed “highly prestigious” recognition on a large number of Arizona State University faculty members.
History
The Arizona State University was established as the Territorial Normal School at Tempe on March 12, 1885, when the 13th Arizona Territorial Legislature passed an act to create a normal school to train teachers for the Arizona Territory. The campus consisted of a single, four-room schoolhouse on a 20-acre plot largely donated by Tempe residents George and Martha Wilson. Classes began with 33 students on February 8, 1886. The curriculum evolved over the years and the name was changed several times; the institution was also known as Tempe Normal School of Arizona (1889–1903), Tempe Normal School (1903–1925), Tempe State Teachers College (1925–1929), Arizona State Teachers College (1929–1945), Arizona State College (1945–1958) and, by a 2–1 margin of the state’s voters, The Arizona State University in 1958.
In 1923, the school stopped offering high school courses and added a high school diploma to the admissions requirements. In 1925, the school became the Tempe State Teachers College and offered four-year Bachelor of Education degrees as well as two-year teaching certificates. In 1929, the 9th Arizona State Legislature authorized Bachelor of Arts in Education degrees as well, and the school was renamed The Arizona State Teachers College. Under the 30-year tenure of president Arthur John Matthews (1900–1930), the school was given all-college student status. The first dormitories built in the state were constructed under his supervision in 1902. Of the 18 buildings constructed while Matthews was president, six are still in use. Matthews envisioned an “evergreen campus,” with many shrubs brought to the campus, and implemented the planting of 110 Mexican Fan Palms on what is now known as Palm Walk, a century-old landmark of the Tempe campus.
During the Great Depression, Ralph Waldo Swetman was hired to succeed President Matthews, coming to The Arizona State Teachers College in 1930 from The Humboldt State Teachers College where he had served as president. He served a three-year term, during which he focused on improving teacher-training programs. During his tenure, enrollment at the college doubled, topping the 1,000 mark for the first time. Matthews also conceived of a self-supported summer session at the school at The Arizona State Teachers College, a first for the school.
1930–1989
In 1933, Grady Gammage, then president of The Arizona State Teachers College at Flagstaff, became president of The Arizona State Teachers College at Tempe, beginning a tenure that would last for nearly 28 years, second only to Swetman’s 30 years at the college’s helm. Like President Arthur John Matthews before him, Gammage oversaw the construction of several buildings on the Tempe campus. He also guided the development of the university’s graduate programs; the first Master of Arts in Education was awarded in 1938, the first Doctor of Education degree in 1954 and 10 non-teaching master’s degrees were approved by the Arizona Board of Regents in 1956. During his presidency, the school’s name was changed to Arizona State College in 1945, and finally to The Arizona State University in 1958. At the time, two other names were considered: Tempe University and State University at Tempe. Among Gammage’s greatest achievements in Tempe was the Frank Lloyd Wright-designed construction of what is Grady Gammage Memorial Auditorium/ASU Gammage. One of the university’s hallmark buildings, Arizona State University Gammage was completed in 1964, five years after the president’s (and Wright’s) death.
Gammage was succeeded by Harold D. Richardson, who had served the school earlier in a variety of roles beginning in 1939, including director of graduate studies, college registrar, dean of instruction, dean of the College of Education and academic vice president. Although filling the role of acting president of the university for just nine months (Dec. 1959 to Sept. 1960), Richardson laid the groundwork for the future recruitment and appointment of well-credentialed research science faculty.
By the 1960s, under G. Homer Durham, the university’s 11th president, The Arizona State University began to expand its curriculum by establishing several new colleges and, in 1961, the Arizona Board of Regents authorized doctoral degree programs in six fields, including Doctor of Philosophy. By the end of his nine-year tenure, The Arizona State University had more than doubled enrollment, reporting 23,000 in 1969.
The next three presidents—Harry K. Newburn (1969–71), John W. Schwada (1971–81) and J. Russell Nelson (1981–89), including and Interim President Richard Peck (1989), led the university to increased academic stature, the establishment of The Arizona State University West campus in 1984 and its subsequent construction in 1986, a focus on computer-assisted learning and research, and rising enrollment.
1990–present
Under the leadership of Lattie F. Coor, president from 1990 to 2002, The Arizona State University grew through the creation of the Polytechnic campus and extended education sites. Increased commitment to diversity, quality in undergraduate education, research, and economic development occurred over his 12-year tenure. Part of Coor’s legacy to the university was a successful fundraising campaign: through private donations, more than $500 million was invested in areas that would significantly impact the future of The Arizona State University. Among the campaign’s achievements were the naming and endowing of Barrett, The Honors College, and the Herberger Institute for Design and the Arts; the creation of many new endowed faculty positions; and hundreds of new scholarships and fellowships.
In 2002, Michael M. Crow became the university’s 16th president. At his inauguration, he outlined his vision for transforming The Arizona State University into a “New American University”—one that would be open and inclusive, and set a goal for the university to meet Association of American Universities criteria and to become a member. Crow initiated the idea of transforming The Arizona State University into “One university in many places”—a single institution comprising several campuses, sharing students, faculty, staff and accreditation. Subsequent reorganizations combined academic departments, consolidated colleges and schools, and reduced staff and administration as the university expanded its West and Polytechnic campuses. The Arizona State University’s Downtown Phoenix campus was also expanded, with several colleges and schools relocating there. The university established learning centers throughout the state, including The Arizona State University Colleges at Lake Havasu City and programs in Thatcher, Yuma, and Tucson. Students at these centers can choose from several Arizona State University degree and certificate programs.
During Crow’s tenure, and aided by hundreds of millions of dollars in donations, The Arizona State University began a years-long research facility capital building effort that led to the establishment of the Biodesign Institute at The Arizona State University, the Julie Ann Wrigley Global Institute of Sustainability, and several large interdisciplinary research buildings. Along with the research facilities, the university faculty was expanded, including the addition of Nobel Laureates. Since 2002, the university’s research expenditures have tripled and more than 1.5 million square feet of space has been added to the university’s research facilities.
The economic downturn that began in 2008 took a particularly hard toll on Arizona, resulting in large cuts to The Arizona State University ‘s budget. In response to these cuts, The Arizona State University capped enrollment, closed some four dozen academic programs, combined academic departments, consolidated colleges and schools, and reduced university faculty, staff and administrators; however, with an economic recovery underway in 2011, the university continued its campaign to expand the West and Polytechnic Campuses, and establish a low-cost, teaching-focused extension campus in Lake Havasu City.
The Arizona State University’s research funding has almost tripled. Degree production has increased by 45 percent. And thanks to an ambitious aid program, enrollment of students from Arizona families below poverty is up 647 percent.”
In 2015, the Thunderbird School of Global Management became the fifth Arizona State University campus, as the Thunderbird School of Global Management at The Arizona State University. Partnerships for education and research with Mayo Clinic established collaborative degree programs in health care and law, and shared administrator positions, laboratories and classes at the Mayo Clinic Arizona campus.
The Beus Center for Law and Society, the new home of The Arizona State University’s Sandra Day O’Connor College of Law, opened in fall 2016 on the Downtown Phoenix campus, relocating faculty and students from the Tempe campus to the state capital.
sciencesprings 