[1][2] 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.

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.

As pointed out in a key paper by Jacob Bjerknes and Halvor Solberg (1895-1974) in 1922, the dynamics of the polar front, integrated with the cyclone model, provided the major mechanism for north-south heat transport in the atmosphere.

In 1940, he emigrated to the United States, where he headed a government-sponsored meteorology annex for weather forecasting, at the department of physics of the University of California, Los Angeles.

As a professor at the University of California, he was the first to see a connection between unusually warm sea-surface temperatures and the weak easterlies and heavy rainfall that accompany low-index conditions[clarification needed].

At UCLA, Bjerknes and fellow Norwegian-American meteorologist, Jorgen Holmboe, further developed the pressure tendency and the extratropical cyclone theories.