1991Basic SciencesEarth and Planetary Sciences, Astronomy and Astrophysics
Edward Norton Lorenz photo

Edward Norton Lorenz

  • U.S.A. / 1917-2008
  • Meteorologist
  • Professor Emeritus, Massachusetts Institute of Technology

Outstanding Contribution to Earth Science and Mathematical Science by the Development of Theoretical Basis of Numerical Study in Meteorology and the Discovery of Deterministic Chaos

A meteorologist who established the theoretical basis of weather and climate predictability, as well as the basis for computer-aided atmospheric physics and meteorology. He made his boldest scientific achievement in discovering "deterministic chaos," a principle which has 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.


Brief Biography

Born in Connecticut, U.S.A.
A.B. (Mathematics), Dartmouth College
Sc. D. (Meteorology), M.I.T.
Research Staff, M.I.T.
Professor, M.I.T.
Professor Emeritus, M.I.T.

Selected Awards and Honors

Carl Gustaf Rossby Research Medal, American Meteorological Society
Symons Memorial Gold Medal, Royal Mateorological Society
Fellow, National Academy of Sciences (U.S.A.)
Member, Norwegian Academy of Science and Letters
Crafoord Prize, Royal Swedish Academy of Sciences
Honorary Member, Royal Mateorological Society

Major Works


Available potential energy and the maintenance of the general circulation. Tellus. Vol.7


Deterministic nonperiodic flow. Journal of Atmospheric Sciences. Vol.20


The nature and theory of the general circulation of atmosphere. World Meteorological Organization. No.218


Three approaches to atmospheric predictability. Bull. American Meteorological Society. Vol.50


Nondeterministic theories of climate change. Quaternary Research. Vol.6


Can chaos and intransitivity lead to interannual variability? Tellus. Vol.42A


Outstanding Contribution to Earth Science and Mathematical Science by the Development of Theoretical Basis of Numerical Study in Meteorology and the Discovery of Deterministic Chaos

Dr. Edward Norton Lorenz is recognized world-wide not only as one of the outstanding theoretical meteorologists of our day, but also as a pioneer in the new major area of scientific study known as “deterministic chaos,” which has applications in many fields ranging from pure mathematics to physics, engineering, chemistry, biology, economics and geology as well as his own field of atmospheric science.

As a theoretical meteorologist, he refined the concept of available potential energy and formulated the equations governing the energetics of the atmospheric general circulation. He then simplified these equations to form a basis for numerical prediction of weather and climate by computer models. His mathematical methodology has been widely used in making numerical simulations of the atmospheric circulation in connection with global ecological problems.

In the study of thermal convection in the gravitational field, he introduced the use of low-order truncated representations of atmospheric dynamics to elucidate the fundamental physics of atmospheric flow phenomena with minimal sets of nonlinear ordinary differential equations. This approach led to his discovery of the first system of differential equations, a dissipative system with a degree of freedom of only three, whose solution constitutes the prototypical example of deterministic chaos. He discovered that deterministic nonlinear dynamics can produce what he called “the butterfly effect,” in which a minute change in an initial state may well result in a huge difference in a future state. Furthermore, by introducing the notions of transitivity and intransitivity, he clarified the complexity of the climatic system and gave a theoretical basis for abrupt climatic changes.

Dr. Lorenz’s discovery of deterministic chaos gave a clear mathematical explanation for the ubiquitous lack of predictability and thus revolutionalized our understanding of nature in all of the sciences and beyond. It is for these reasons that Dr. Lorenz is most deserving of the 1991 Kyoto Prize for Basic Sciences.


Abstract of the Lecture

A Scientist by Choice

I offer the proposition that in order to become an accomplished scientist, one must have an intense interest in the subject matter of science, must have true ability to identify and solve fundamental problems in one’s chosen field, and must be welling to question any commonly accepted explanation that is not logically and cliarly stated, rejecting it and seeking a new explanation if it cannot be acceptably restated.

In seeking to support my assertions I use my own life as a case study, recounting my scientific and nonscientific interests as a child, my pursuit of mathematics in college and graduate school, my subsequent schooling in meteorology, my choice of meteorology as a career, and the circumstances leading to my most significant contributions. I indicate that the atmosphere behaves chaotically, and discuss how this situation affects the manner in which meteorological research should be conducted.

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From Weather Forecasting to Chaos

November 12, 1991 (Tue.) 13:00-17:25
Kyoto International Conference Center


Organization Members: Masaya Yamamoto (Professor, Faculty of Science and Technology, Ryukoku University)
Ryozaburo Yamamoto (Member, the Kyoto Prize Screening Committee in Basic Sciences; Professor Emeritus, Kyoto University)
Isamu Hirota (Professor, Faculty of Science, Kyoto University)
Humitaka Sato (Member, the Kyoto Prize Screening Committee in Basic Sciences; Professor, Faculty of Science, Kyoto University)
Greetings Kazuo Inamori
President, The Inamori Foundation
Opening Remarks Heisuke Hironaka
Chairman, the Kyoto Prize Screening Committee in Basic Sciences;
Professor, Harvard University
Chairperson: Ryozaburo Yamamoto
Introduction of the Laureate Isamu Hirota
Lecture Edward Norton Lorenz
Laureate in Basic Sciences
"How Good Can Weather Forecasting Become?–The Start of a Theory"
Chairperson: Isamu Hirota
Lecture Shigeo Yoden
Associate Professor, Faculty of Science, Kyoto University
"Local Lyapunov Stability and Atmospheric Predictability"
Lecture Hiroshi Kokubu
Lecturer, Faculty of Sciences, Kyoto University
"Bifurcations of Homoclinic and Heteroclinic Orbits and Chaos"
Chairperson: Humitaka Sato
Lecture Yasuji Sawada
Professor, Research Institute of Electrical Communication, Tohoku University
"Chaos in Thermal Convection"
Lecture Ichiro Tsuda
Associate Professor, Faculty of Computer Science and Systems Engineering, Kyushu Institute of Technology
"Chaotic Computation in Biological Systems"
Closing Remarks Masaya Yamaguchi