Edward Norton Lorenz (May 23, 1917 – April 16, 2008) was an American mathematician and

meteorologist A meteorologist is a scientist who studies and works in the field of meteorology aiming to understand or predict Earth's atmospheric phenomena including the weather. Those who study meteorological phenomena are meteorologists in research, while t ...

who established the theoretical basis of weather and climate

predictability Predictability is the degree to which a correct prediction or forecast of a system's state can be made, either qualitatively or quantitatively. Predictability and causality Causal determinism has a strong relationship with predictability. Per ...

, as well as the basis for computer-aided

atmospheric physics Within the atmospheric sciences, atmospheric physics is the application of physics to the study of the atmosphere. Atmospheric physicists attempt to model Earth's atmosphere and the atmospheres of the other planets using fluid flow equations, chem ...

and

meteorology Meteorology is a branch of the atmospheric sciences (which include atmospheric chemistry and physics) with a major focus on weather forecasting. The study of meteorology dates back millennia, though significant progress in meteorology did no ...

. He is best known as the founder of modern chaos theory, a branch of mathematics focusing on the behavior of

dynamical system In mathematics, a dynamical system is a system in which a function describes the time dependence of a point in an ambient space. Examples include the mathematical models that describe the swinging of a clock pendulum, the flow of water in ...

s that are highly sensitive to

initial conditions In mathematics and particularly in dynamic systems, an initial condition, in some contexts called a seed value, is a value of an evolving variable at some point in time designated as the initial time (typically denoted ''t'' = 0). For ...

. His discovery of deterministic chaos "profoundly influenced a wide range of basic sciences and brought about one of the most dramatic changes in mankind's view of nature since Sir Isaac Newton," according to the committee that awarded him the 1991

Kyoto Prize The is Japan's highest private award for lifetime achievement in the arts and sciences. It is given not only to those that are top representatives of their own respective fields, but to "those who have contributed significantly to the scientific, ...

for basic sciences in the field of earth and planetary sciences.

Biographical information

Lorenz was born in 1917 in

West Hartford, Connecticut West Hartford is a town in Hartford County, Connecticut, United States, west of downtown Hartford, Connecticut, Hartford. The population was 64,083 at the 2020 United States Census, 2020 census. The town's popular downtown area is colloquially ...

. He acquired an early love of science from both sides of his family. His father, Edward Henry Lorenz (1882-1956), majored in mechanical engineering at the

Massachusetts Institute of Technology The Massachusetts Institute of Technology (MIT) is a private land-grant research university in Cambridge, Massachusetts. Established in 1861, MIT has played a key role in the development of modern technology and science, and is one of the ...

, and his maternal grandfather, Lewis M. Norton, developed the first course in chemical engineering at

MIT The Massachusetts Institute of Technology (MIT) is a private land-grant research university in Cambridge, Massachusetts. Established in 1861, MIT has played a key role in the development of modern technology and science, and is one of the m ...

in 1888. Meanwhile, his mother, Grace Peloubet Norton (1887-1943), instilled in Lorenz a deep interest in games, particularly chess. Later in life, Lorenz lived in

Cambridge, Massachusetts Cambridge ( ) is a city in Middlesex County, Massachusetts, United States. As part of the Boston metropolitan area, the cities population of the 2020 U.S. census was 118,403, making it the fourth most populous city in the state, behind Boston ...

with his wife, Jane Loban, and their three children, Nancy, Cheryl, and Edward. He was an avid outdoorsman, who enjoyed hiking, climbing, and cross-country skiing. He kept up with these pursuits until very late in his life. On April 16, 2008, Lorenz died at his home in Cambridge from cancer at the age of 90.

Education

Lorenz received a bachelor's degree in mathematics from

Dartmouth College Dartmouth College (; ) is a private research university in Hanover, New Hampshire. Established in 1769 by Eleazar Wheelock, it is one of the nine colonial colleges chartered before the American Revolution. Although founded to educate Native ...

in 1938 and a master's degree in mathematics from Harvard in 1940. He worked as a

weather forecaster A meteorologist is a scientist who studies and works in the field of meteorology aiming to understand or predict Earth's atmospheric phenomena including the weather. Those who study meteorological phenomena are meteorologists in research, while t ...

for the

United States Army Air Forces The United States Army Air Forces (USAAF or AAF) was the major land-based aerial warfare service component of the United States Army and ''de facto'' aerial warfare service branch of the United States during and immediately after World War II ...

during

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...

, leading him to pursue graduate studies in meteorology at the

. He earned both a master's and doctoral degree in

from

in 1943 and 1948. His doctoral dissertation, titled "A Method of Applying the Hydrodynamic and Thermodynamic Equations to Atmospheric Models" and performed under advisor James Murdoch Austin, described an application of fluid dynamical equations to the practical problem of predicting the motion of storms.

Scientific career

Lorenz spent the entirety of his scientific career at the

. In 1948, he joined the MIT Department of Meteorology as a research scientist. In 1955, he became an assistant professor in the department and was promoted to professor in 1962. From 1977 to 1981, Lorenz served as head of the Department of Meteorology at MIT. In 1983, the MIT Department of Meteorology and Physical Oceanography merged with the Department of Geology to become the current MIT Department of Earth, Atmospheric and Planetary Sciences, where Lorenz remained a professor before becoming an emeritus professor in 1987.

Atmospheric circulation

In the late 1940s and early 1950s, Lorenz worked with Victor Starr on the General Circulation Project at MIT to understand the role the weather system played in determining the energetics of the general circulation of the atmosphere. From this work, in 1967, Lorenz published a landmark paper, titled "The Nature and Theory of the General Circulation of the Atmosphere," on

atmospheric circulation Atmospheric circulation is the large-scale movement of air and together with ocean circulation is the means by which thermal energy is redistributed on the surface of the Earth. The Earth's atmospheric circulation varies from year to year, bu ...

from an energetic perspective, which advanced the concept of available potential energy.

Numerical weather prediction

In the 1950s, Lorenz became interested in and started work on

numerical weather prediction Numerical weather prediction (NWP) uses mathematical models of the atmosphere and oceans to predict the weather based on current weather conditions. Though first attempted in the 1920s, it was not until the advent of computer simulation in th ...

, which relied on computers to forecast weather by processing observational data on such things as temperature, pressure, and wind. This interest was sparked, in part, after a visit to the

Institute for Advanced Study The Institute for Advanced Study (IAS), located in Princeton, New Jersey, in the United States, is an independent center for theoretical research and intellectual inquiry. It has served as the academic home of internationally preeminent schola ...

in Princeton, New Jersey, where he met

Jule Charney Jule Gregory Charney (January 1, 1917 – June 16, 1981) was an American meteorologist who played an important role in developing numerical weather prediction and increasing understanding of the general circulation of the atmosphere by devisin ...

, then head of the IAS's Meteorological Research Group and a leading dynamical meteorologist at the time. (Charney would later join Lorenz at

in 1957 as a professor of meteorology.) In 1953, Lorenz took over leadership of a project at MIT that ran complex simulations of weather models that he used to evaluate statistical forecasting techniques. By the late 1950s, Lorenz was skeptical of the appropriateness of the

linear Linearity is the property of a mathematical relationship ('' function'') that can be graphically represented as a straight line. Linearity is closely related to '' proportionality''. Examples in physics include rectilinear motion, the linear ...

statistical models in meteorology, as most atmospheric phenomena involved in weather forecasting are non-linear. It was during this time that his discovery of deterministic chaos came about.

Chaos theory

In 1961, Lorenz was using a simple digital computer, a

Royal McBee The Royal Typewriter Company is a manufacturer of typewriters founded in January 1904. It was headquartered in New York City with its factory in Hartford, Connecticut. History The Royal Typewriter Company was founded by Edward B. Hess and Lewis ...

LGP-30 The LGP-30, standing for Librascope General Purpose and then Librascope General Precision, was an early off-the-shelf computer. It was manufactured by the Librascope company of Glendale, California (a division of General Precision Inc.), and s ...

, to simulate weather patterns by modeling 12 variables, representing things like temperature and wind speed. He wanted to see a sequence of data again, and to save time he started the simulation in the middle of its course. He did this by entering a printout of the data that corresponded to conditions in the middle of the original simulation. To his surprise, the weather that the machine began to predict was completely different from the previous calculation. The culprit: a rounded decimal number on the computer printout. The computer worked with 6-digit precision, but the printout rounded variables off to a 3-digit number, so a value like 0.506127 printed as 0.506. This difference is tiny, and the consensus at the time would have been that it should have no practical effect. However, Lorenz discovered that small changes in initial conditions produced large changes in long-term outcome. Lorenz's discovery, which gave its name to Lorenz attractors, showed that even detailed atmospheric modelling cannot, in general, make precise long-term weather predictions. His work on the topic, assisted by Ellen Fetter, culminated in the publication of his 1963 paper "Deterministic Nonperiodic Flow" in ''

Journal of the Atmospheric Sciences The ''Journal of the Atmospheric Sciences'' (until 1962 titled ''Journal of Meteorology'') is a scientific journal published by the American Meteorological Society. It covers basic research related to the physics, dynamics, and chemistry of the ...

'', and with it, the foundation of chaos theory. He states in that paper: His description of the butterfly effect, the idea that small changes can have large consequences, followed in 1969. Lorenz's insights on deterministic chaos resonated widely starting in the 1970s and 80s, when it spurred new fields of study in virtually every branch of science, from biology to geology to physics. In meteorology, it led to the conclusion that it may be fundamentally impossible to predict weather beyond two or three weeks with a reasonable degree of accuracy. However, the recognition of chaos has led to improvements in

weather forecasting Weather forecasting is the application of science and technology to predict the conditions of the atmosphere for a given location and time. People have attempted to predict the weather informally for millennia and formally since the 19th cent ...

, as now forecasters recognize that measurements are imperfect and thus run many simulations starting from slightly different conditions, called

ensemble forecasting Ensemble forecasting is a method used in or within numerical weather prediction. Instead of making a single forecast of the most likely weather, a set (or ensemble) of forecasts is produced. This set of forecasts aims to give an indication of the ...

. Of the seminal significance of Lorenz's work, Kerry Emanuel, a prominent meteorologist and climate scientist at MIT, has stated: Late in his career, Lorenz began to be recognized with international accolades for the importance of his work on deterministic chaos. In 1983, along with colleague

Henry Stommel Henry Melson Stommel (September 27, 1920 – January 17, 1992) was a major contributor to the field of physical oceanography. Beginning in the 1940s, he advanced theories about global ocean circulation patterns and the behavior of the Gulf Stream ...

, he was awarded the

Crafoord Prize The Crafoord Prize is an annual science prize established in 1980 by Holger Crafoord, a Swedish industrialist, and his wife Anna-Greta Crafoord. The Prize is awarded in partnership between the Royal Swedish Academy of Sciences and the Crafoord Foun ...

from the Swedish Academy of Sciences, considered to be nearly equal to a

Nobel Prize The Nobel Prizes ( ; sv, Nobelpriset ; no, Nobelprisen ) are five separate prizes that, according to Alfred Nobel's will of 1895, are awarded to "those who, during the preceding year, have conferred the greatest benefit to humankind." Alfr ...

. He was also awarded the

for basic sciences in the field of earth and planetary sciences in 1991, the Buys Ballot Award in 2004, and the

Tomassoni Award Tomassoni awards was the overarching name of two prizes for outstanding achievements in physics, the Premio Felice Pietro Chisesi e Caterina Tomassoni and the Premio Caterina Tomassoni e Felice Pietro Chisesi. The two prizes were awarded every one ...

in 2008. In 2018, a short documentary was made about Lorenz's immense scientific legacy on everything from how we predict weather to our understanding of the universe.

Legacy

Lorenz is remembered by colleagues and friends for his quiet demeanor, gentle humility, and love of nature. He was described as "a genius with a soul of an artist" by his close friend and collaborator

The Lorenz Center

In 2011, The Lorenz Center, a climate think tank devoted to fundamental scientific inquiry, was founded at

in honor of Lorenz and his pioneering work on chaos theory and

climate science Climatology (from Greek , ''klima'', "place, zone"; and , '' -logia'') or climate science is the scientific study of Earth's climate, typically defined as weather conditions averaged over a period of at least 30 years. This modern field of stu ...

Centenary celebration

In February 2018, The Edward Lorenz Center and Henry Houghton Fund hosted a symposium, named MIT on Chaos and Climate, in honor of the 100th anniversary of the birth of Lorenz and Charney. The two-day event featured presentations from world-renowned experts on the many scientific contributions that the two pioneers made on the fields of

, physical oceanography, atmospheric dynamics, and experimental fluid dynamics, as well as the personal legacy they left behind of integrity, optimism, and collaboration. A video produced for the event highlights the indelible mark made by Charney and Lorenz on MIT and the field of meteorology as a whole.

Publications

Lorenz published many books and articles, a selection of which can be found below. A more complete list can be found on the Lorenz Center website
link
* 1955 Available potential energy and the maintenance of the general circulation. ''Tellus''. Vol. 7; 2
Link
* 1963 Deterministic nonperiodic flow. ''Journal of the Atmospheric Sciences''. Vol. 20: 130–141.
Link
* 1967 The nature and theory of the general circulation of atmosphere. ''World Meteorological Organization''. Vol. 218
Link
* 1969 Three approaches to atmospheric predictability. ''Bulletin of the American Meteorological Society''. Vol. 50; 345–349
Link
* 1972 Predictability: Does the Flap of a Butterfly's Wings in Brazil Set Off a Tornado in Texas? ''American Association for the Advancement of Sciences;'' 139th meeting
Link
* 1976 Nondeterministic theories of

climate change In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to ...

. ''Quaternary Research''. Vol. 6
Link
* 1990 Can chaos and intransitivity lead to interannual variability? ''Tellus''. Vol. 42A
Link
* 2005 Designing Chaotic Models. ''Journal of the Atmospheric Sciences''. Vol. 62, No. 5: 1574–1587
Link

Awards

* 1969 Carl-Gustaf Rossby Research Medal,

American Meteorological Society The American Meteorological Society (AMS) is the premier scientific and professional organization in the United States promoting and disseminating information about the atmospheric, oceanic, and hydrologic sciences. Its mission is to advance th ...

. * 1973 Symons Gold Medal,

Royal Meteorological Society The Royal Meteorological Society is a long-established institution that promotes academic and public engagement in weather and climate science. Fellows of the Society must possess relevant qualifications, but Associate Fellows can be lay enthus ...

. * 1975 Fellow, National Academy of Sciences (U.S.A.). * 1981 Member,

Norwegian Academy of Science and Letters The Norwegian Academy of Science and Letters ( no, Det Norske Videnskaps-Akademi, DNVA) is a learned society based in Oslo, Norway. Its purpose is to support the advancement of science and scholarship in Norway. History The Royal Frederick Unive ...

. * 1983

, Royal Swedish Academy of Sciences. * 1984 Honorary Member,

. * 1989 Elliott Cresson Medal,

The Franklin Institute The Franklin Institute is a science museum and the center of science education and research in Philadelphia, Pennsylvania. It is named after the American scientist and statesman Benjamin Franklin. It houses the Benjamin Franklin National Memori ...

* 1991

for … his boldest scientific achievement in discovering "deterministic chaos" . * 1992 Roger Revelle Medal * 2000

International Meteorological Organization Prize The International Meteorological Organization Prize is awarded annually by the World Meteorological Organization (WMO) for outstanding contributions in the field of meteorology and, since 1971, the field of operational hydrology. The prize, estab ...

from

World Meteorological Organization The World Meteorological Organization (WMO) is a specialized agency of the United Nations responsible for promoting international cooperation on atmospheric science, climatology, hydrology and geophysics. The WMO originated from the Intern ...

* 2004 Buys Ballot Medal of the Royal Netherlands Academy of Arts and Sciences. * 2004

Lomonosov Gold Medal The Lomonosov Gold Medal (russian: Большая золотая медаль имени М. В. Ломоносова ''Bol'shaya zolotaya medal' imeni M. V. Lomonosova''), named after Russian scientist and polymath Mikhail Lomonosov, is awarded ...

of the

Russian Academy of Sciences The Russian Academy of Sciences (RAS; russian: Росси́йская акаде́мия нау́к (РАН) ''Rossíyskaya akadémiya naúk'') consists of the national academy of Russia; a network of scientific research institutes from across ...

References

External links

"Weather and Chaos: The Work of Edward N. Lorenz," 2018
* ttps://www.telegraph.co.uk/news/obituaries/1895916/Professor-Edward-Lorenz.html Obituary ''

The Daily Telegraph ''The Daily Telegraph'', known online and elsewhere as ''The Telegraph'', is a national British daily broadsheet newspaper published in London by Telegraph Media Group and distributed across the United Kingdom and internationally. It was f ...

'', 18 April 2008.
Kerry Emanuel, "Edward Norton Lorenz", Biographical Memoirs of the National Academy of Sciences (2011)
{{DEFAULTSORT:Lorenz, Edward 1917 births 2008 deaths 20th-century American mathematicians 21st-century American mathematicians American meteorologists United States Army Air Forces personnel of World War II Carl-Gustaf Rossby Research Medal recipients Chaos theorists Dartmouth College alumni Foreign Members of the Royal Society Foreign Members of the USSR Academy of Sciences Foreign Members of the Russian Academy of Sciences Harvard University alumni Kyoto laureates in Basic Sciences Massachusetts Institute of Technology School of Science alumni Massachusetts Institute of Technology School of Science faculty Members of the United States National Academy of Sciences People from West Hartford, Connecticut Recipients of the Buys Ballot Medal (Netherlands) United States Army Air Forces soldiers Recipients of the Lomonosov Gold Medal