# Mathematical Digest

### Short Summaries of Articles about Mathematics

in the Popular Press

"The Weatherman," by Brian Hayes. *American Scientist,* January-February2001.

In 1917, Louis Fry Richardson was driving an ambulance for the French army onthe Western Front. At the same time, in spare moments behind the lines, he wascompleting a vast project of mathematical calculations. His goal was to followthe development of the weather for a six-hour interval in a small area ofcentral Europe.

Even a forecast of such limited scope called for a calculation of dauntingcomplexity. In fact, despite his meticulousness, Richardson predicted that thebarometric pressure would change significantly on a day that saw little change.What went wrong? Irish metereologist Peter Lynch has reconstructed thecalculation and pinpointed Richardson's error in his wind measurement. Lynchdetermined that simple filtering of the wind data could have vastly improvedRichardson's predictions and given him the recognition he deserved in his owntime. For although he incorrectly predicted the weather, Richardson predictedthe future of weather prediction.

*--- Ben Stein*