ALD21: Klára Dán von Neumann, Computer Scientist

Klára Dán von Neumann

Klára Dán von Neumann

An early computer programmer, Klára Dán von Neumann led the team that produced the first computer-generated 12-hour and 24-hour retrospective weather forecasts. Despite having had little mathematical education, she became one of the primary programmers for the Electronic Numerical Integrator and Computer (ENIAC) for this project.

In the late 1940s, Dán von Neumann worked with her husband, John von Neumann, on turning the ENIAC into one of the first stored-program computers, able to run programs that had been stored in binary code on a memory device. Until then programs had to be entered and re-entered by hand.

The ENIAC then became the focus of The Meteorology Project, which aimed to use the computer to generate weather forecasts. Using data from past storms, they produced two 12-hour and 24-hour retrospective forecasts. Not only was that the first time a weather forecast had been produced by computer, it was also the first time a computer had been used to conduct a physics experiment.

Dán von Neumann was instrumental to the project, checking the final code for the experiment, training programmers, hand-punching and managing the 100,000 punch-cards that were used for storing the program, and ensuring that no data was lost. This was difficult and highly technical work.

Born in Hungary in 1911, Klára won the national figure skating championship aged just 14. She married John von Neumann in 1938, and the couple moved to the US because of the rising antisemitism in Europe.

Further reading

Posted in Ada Lovelace Day 2021.