The Nature of the
Atmosphere
Year of Discovery: 1960
What Is It? The atmosphere is chaotic and unpredictable.
Who Discovered It? Ed Lorenz
Why Is This One of the 100 Greatest?
Ed Lorenz uncovered a nonlinear, complex, interdependent system of equations that
describe the real movement of the atmosphere. He showed that atmospheric models are so
dependent on initial and boundary conditions (starting data supplied to the model) that even
seemingly infinitesimal changes in them create major changes in the system. In other
words, when a butterfly flaps its wings over Beijing, the models might well predict that it
will change the weather in New York. But everyone admitted that just couldn’t happen.
Lorenz discovered not how to make long-range predictions, but rather the forces that
make such predictions impossible. He then developed chaos theory—the study of chaotic
and unpredictable systems. Scientists are discovering that many natural, biological, and environmental systems are best described and better understood under chaos theory than
through traditional forms of analysis.
How Was It Discovered?
Having a computer was enough of a novelty in 1958 to entice many MIT faculty and
students to make the trip to Ed Lorenz’s office just to watch the thing work. But excitement
quickly turned to despair for Lorenz.
Lorenz created a set of equations to act as a mathematical model of atmospheric storm
movement and behavior. He noticed that tiny changes in the starting conditions of the
model soon produced enormous changes in the outcome. Tiny starting differences always
amplified over time, rather than damping, or normalizing out.
If the actual atmosphere acted like Lorenz’s models, he had just proved that long-range
weather forecasting was impossible since starting conditions were never known with
enough precision to prevent chaotic, amplified error. It was an unsettling and sinking feeling to trade the excitement of finding a new research tool for the despair of proving that your
field and work were both inherently flawed and impossible.
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