Duration‐frequencies of low ceilings in climatology

Abstract

The parallel growth of weather information for the special benefit of aviation and the use of punched‐cards in climatology is discussed, with the notation that very little use, in a climatological sense, had been made of the weather data designed for aviation until the beginning of World War II. The various types of climatic summaries in common use are described, and it is noted that they are not particularly well adapted to airways weather information, such as ceilings and visibility. By the use of punched‐card methods of machine tabulation, special and more complex types of climatic summaries are available. The use of duration frequencies of the limiting categories of airways weather data is considered to more closely approximate the operational needs of aviation and other interests than any other type of summary.