4 - Meteorology, the New Science of the Stars and the Rise of Weather Forecasting

Summary

Chapetr 4 traces the reception and adaptation of Islamicate meteorology by writers and scientists in Northern and Western Europe. Fundamental to this was the growing body of planetary tables, based on versions of Ptolemy’s work, which made it possible to calculate the positions of the planets with much greater accuracy. The chapter traces the works of Latin astrometeorology that drew on this ability, and gives outlines of the processes involved in making actual weather forecasts, according to rival methods. Pioneers were Hermann of Carinthia, Robert of Ketton and John of Seville, who all made translations and then issued new treatises on the subject. Manuscript evidence for the transmission of this new astrometeorology is discussed. The roles of astrological textbooks, especially the Book of Nine Judges, are considered. The concluding part of the chapter weighs up the popularity of astrometeorological forecasting across Europe by the early thirteenth century, and argues that it was closely associated with the emergence of a new, highly technical, scientific discourse.