Bjørn Helland-Hansen (16 October 1877 – 7 September 1957) was a Norwegian pioneer in the field of modern oceanography. He studied the variation patterns of the weather in the northern Atlantic Ocean and of the atmosphere. In 1933 he was awarded the Alexander Agassiz Medal. From 1946 to 1948, Helland-Hansen was President of the International Union of Geodesy and Geophysics (IUGG). He was a member of the Prussian Academy of Sciences and a member of the Member of the Academy of Sciences of the German Democratic Republic (DDR).