From 1911 he was a professor of meteorology at the University of Graz, and from 1923 to 1937 was a professor at the University of Berlin. During his tenure at Berlin, he also spent several years as director of the Prussian Meteorological Institute. From 1937 until his retirement in 1952, he was a professor at University of Vienna and director of the Zentralanstalt für Meteorologie und Geodynamik (Central Institute for Meteorology and Geodynamics (ZAMG).
In 1906 and 1910, while based in Innsbruck, Ficker performed extensive scientific studies involving the dynamics of Alpine foehn winds. Among his writings concerning this meteorological phenomena was Föhn und Föhnwirkungen (Foehn and Foehn Effects), a treatise he co-authored with biometeorologist Bernhard de Rudder (1894-1962). Ficker is also remembered for important research of cold fronts and heat waves that occur in Russia and northern Asia.