Born in Innichen, County of Tyrol, Supan was first educated at the Laibach gymnasium.
From 1871 to 1875 he worked as a teacher in the Realschule in Laibach, and afterwards studied various sciences in Graz, Halle and Leipzig.
[2] In 1877 he became a gymnasium teacher in Czernowitz, where in 1880 he was named an associate professor of geography at the university.
In 1884 became editor of Petermann's Mitteilungen in Gotha, retaining this post until 1909, when he accepted the chair of geography at Breslau.
[1][2] His original contributions to geographical science were mainly in the fields of climatology and oceanography.