Rossby, Carl-Gustaf (Arvid) (1898–1957)

Swedish-born US meteorologist. He discovered what are now known as Rossby waves, a description of the flow of air within the jet stream, and the Rossby equation, that calculates how fast the flow develops. A medal bearing his name is given by the American Meteorological Society to honour significant research.

At the Massachusetts Institute of Technology 1928–39 and the University of Chicago 1941–50, he organized strong meteorological departments. At the US Weather Bureau 1939–41 he redirected scientific efforts to incorporate important Scandinavian advances in the description of weather fronts and storms.

He was born in Stockholm. His early work in meteorology was at the Bergen Institute in Norway under Vilhelm Bjerknes. He went to the USA in 1926 on a one-year fellowship to the US Weather Bureau, married in 1929, and became a US citizen in 1939. He returned to Sweden in 1950 at the request of the Swedish government to help found the Institute of Meteorology at the University of Stockholm.