Carl Rossby (1898?ａ¨1957), Swedish-American meteorologist. Carl-Gustaf Arvid Rossby was the first person to explain the large-scale motions of the atmosphere in terms of fluid dynamics. In 1925, Rossby was granted a fellowship from the Sweden-America Foundation 'to study the application of the polar front theory to American weather'. He is also responsible for the established of the first weather service for civil aviation. Here he is pictured just after he was named Assistant Chief for Research and Education of the United States Weather Bureau. Photographed on 3rd June 1939.