Bjerknes founded the UCLA Department of Meteorology (now the Department of Atmospheric and Oceanic Sciences). 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. At UCLA, Bjerknes and fellow Norwegian-American meteorologist, Jorgen Holmboe, further developed the pressure tendency and the extratropical cyclone theories.