Jacob Bjerknes

Jacob Aall Bonnevie Bjerknes ( , ; 2 November 1897 – 7 July 1975) was a meteorologist. He is known for his key paper in which he pointed the dynamics of the polar front, mechanism for north-south heat transport and for which he was also awarded a doctorate from the University of Oslo. Born in Stockholm, Sweden, he was the son of the Norwegian meteorologist Vilhelm Bjerknes, one of the pioneers of modern weather forecasting. He helped develop the Norwegian cyclone model. He earned a Ph.D. from the University of Oslo in 1924. Bjerknes was part of the team that made the first crossing of the Arctic in the airship Norge. During WWII, he helped the US with the planning of the Hiroshima and Nagasaki atomic bombings. He also helped gain an understanding of the weather phenomenon El Niño. Background Jacob Aall Bonnevie Bjerknes was born in Stockholm, Sweden. His father was the Norwegian meteorologist Vilhelm Bjerknes, one of the pioneers of modern weather forecasting. His paternal grandfather was Norwegian mathematician and physicist Carl Anton Bjerknes. His maternal grandfather was Norwegian politician Jacob Aall Bonnevie, after whom he was named. Professional career Bjerknes was part of a group of meteorologists led by his father, Vilhelm Bjerknes, at the University of Leipzig. Together they developed the model that explains the generation, intensification and ultimate decay (the life cycle) of mid-latitude cyclones, introducing the idea of fronts, that is, sharply defined boundaries between air masses. This concept is known as the Norwegian cyclone model.