Edward Norton Lorenz (born May 23 1917), a research meteorologist at MIT, observed that minute variations in the initial values of variables in his primitive computer weather model (c. 1960) would result in grossly divergent weather (driven by energy from the sun, with key factors being temperature, humidity, atmospheric pressure, cloud cover, wind speed, and elevation.) patterns. This sensitive dependence on initial conditions came to be known as the <font color=red>Butterfly effect </font>.
He went on to explore the underlying mathematics and published his conclusions in a seminal work in the annals of chaos theory, Deterministic Nonperiodic Flow, in which he described a relatively simple system of equations that resulted in a pattern of infinite complexity, the Lorenz attractor.