Jule Charney

Jule Charney was an American meteorologist widely credited with guiding the development of modern meteorology in the decades after the Second World War more than any other single figure in the field. Beginning in 1948 at Princeton's Institute for Advanced Study, Charney worked with mathematician John von Neumann to pioneer numerical weather prediction, the use of computers to forecast weather by numerically solving the physical equations governing atmospheric motion, work that led to the founding of the Joint Numerical Weather Prediction Unit in 1954 and later NOAA's Geophysical Fluid Dynamics Laboratory. Between 1947 and 1948 Charney developed the quasi-geostrophic approximation, a simplified mathematical framework for calculating large-scale atmospheric motion, and he identified baroclinic instability as the physical mechanism responsible for the formation of mid-latitude cyclones. In 1979 Charney chaired a National Research Council study group whose resulting report, generally called the Charney Report, estimated that a doubling of atmospheric carbon dioxide would produce roughly 3 degrees Celsius of warming, an estimate that remained essentially unchanged by later, more sophisticated climate models for more than four decades afterward. Charney spent 25 years, from 1956 until his death in 1981, as a professor at MIT, where he mentored many of the following generation's leading meteorologists.