Cold Front, Warm Front, Battle Front

The invention of weather forecasting in the First World War

The synoptic weather chart is familiar to the average weather news consumer

“Recording weather observations, explaining the action of the atmosphere, and predicting wind and rain are all ancient practices,” science historian Frederik Nebeker writes.¹ Aristotle described the observational form of weather forecasting in Meteorologica some time around 300 BC; Ptolemy described the predictive form, though as astrology rather than science, in Tetrabiblos around 160 AD. “Recording weather observations, explaining the action of the atmosphere, and predicting wind and rain are all ancient practices,” but forecasting was not data-driven. As humans began their struggle to invent weather science during the 18th century, theorists were not empiricists. The observer, the natural philosopher, and the practical meteorologist only converged slowly, painfully. “The three traditions continued their separate developments until the middle of the 20th century,” whereupon “a unification of meteorology” took place in the the 1950s and 60s, Nebeker says.

The First World War proved an especially formative moment. Working for the British Metropolitan Weather Office, Lewis Fry Richardson “devised, during and after World War I, an algorithmic scheme of weather prediction based on the method” of partial differential equations. Richardson worked under William Napier Shaw, who said in 1926 that “the introduction of the weather-map led to a curious alienation of the experimental and theoretical physicists from the study of weather” during the war. Forecasting was “entirely nonquantitative in the period up to World War I,” Nebeker writes. Weather forecasting had become a data-driven physical science by the end of the conflict. “Shortly after World War I a group of meteorologists under [Vilhelm] Bjerknes’s direction in Bergen introduced the concepts of cold and warm fronts, the polar front, and air masses” that are basic to modern forecasting.