dr. edward lorenz built a simplified mathematical model of the way air moves in the earth's atmosphere. working with a 12-variable computerized weaer model, lorenz repeated a calculation involving a numerical representation of a slightly shifting wind condition. to save computation time, he began the simulation in the middle of its course but entered the data by rounding off the original six-digit variables to just three digits, an adjustment of just one one-thousandth from the original setting. but to his surprise, the weather that the computer predicted on this new run, using these slightly different intermediate values, was completely different than his earlier simulations. lorenz expected that the miniscule difference would have practically no effect. by iterating this slightly altered calculation, lorenz realized that minute variations in the initial values in his weather model could result in widely divergent weather patterns. remember, newton showed how an object's motion through space could be predicted by calculating the infinitesimal changes in its path. now lorenz was showing

dr. edward lorenz built a simplified mathematical model of the way air moves in the earth's atmosphere. working with a 12-variable computerized weaer model, lorenz repeated a calculation involving a numerical representation of a slightly shifting wind condition. to save computation time, he began the simulation in the middle of its course but entered the data by rounding off the original six-digit variables to just three digits, an adjustment of just one one-thousandth from the original setting. but to his surprise, the weather that the computer predicted on this new run, using these slightly different intermediate values, was completely different than his earlier simulations. lorenz expected that the miniscule difference would have practically no effect. by iterating this slightly altered calculation, lorenz realized that minute variations in the initial values in his weather model could result in widely divergent weather patterns. remember, newton showed how an object's motion through space could be predicted by calculating the infinitesimal changes in its path. now lorenz was showing