Numerical Weather Prediction from the Mind of von Neumann to Reality and Beyond

Numerical Weather Prediction from The Mind of von Neumann to Reality and Beyond

William Martin, NOAA/NWS Greenville-Spartanburg South Carolina


In this paper, the impact of the work of John von Neumann on Numerical Weather Prediction will be explored.

The history of numerical weather prediction (NWP) has often been traced to the 1950 Tellus paper of Charney et al. that reported on the first successful NWP, and to L. F. Richardson before that who in 1922 manually calculated a numerical weather forecast similar in concept to the Tellus paper which could only be done practically in 1950 after a sufficiently powerful computer had been developed (the ENIAC). In fact, what became NWP can equally be regarded as having started at the Manhattan project of WWII. During the Manhattan project, designing shaped explosives for the spherical implosion needed to set-off the plutonium fission device was a problem in fluid mechanics best solved numerically. This problem, solved by John von Neumann at Los Alamos for nuclear weapons, was very similar to that solved in the 1950 Tellus paper for NWP. Von Neumann also happens to be the third author of the 1950 Tellus paper. As soon as the ENIAC computer became known to him in 1946, Von Neumann seems to have realized that it made NWP practical, and NWP became a pet project of his. Due to von Neumann's reputation, he was able to get the resources needed to make NWP a reality. It was von Neumann who got the money from the military to fund the first NWP project reported on in Tellus, it was von Neumann who brought meteorologist to Princeton to execute the project, and it was von Neumann who got time on the ENIAC to do the calculations. While the group of now famous meteorologists von Neumann brought together did most of the theoretical and practical work needed to execute the first successful NWP, von Neumann himself was busy developing basic computing technology. Von Neumann developed the idea of the stored computer program and had it implemented on the ENIAC (making its use for NWP possible). He further published a series of reports giving a basic design philosophy of electronic computers that was a major breakthrough rapidly taken-up by computer designers world-wide. NWP may have been inevitable, given developments in technology, but the 1950 date of the Tellus paper might easily have been 20 years later had it not been for the third author on that paper who made major advances in the development of computers, and who made NWP one of the first major applications of computers. L. F. Richardson lived to see his dream of NWP become a reality with the 1950 Tellus paper. The same cannot be said of von Neumann who died in 1957. His dream went beyond mere forecasting; he foresaw using NWP as a tool to control the weather. In some ways his vision exceeds even current reality.