Roald Amundsen's contributions to our knowledge of the magnetic fields of the Earth and the Sun

摘要

Roald Amundsen (1872–1928) was known as one of the premier polar explorersin the golden age of polar exploration. His accomplishments clearly documentthat he has contributed to knowledge in fields as diverse as ethnography,meteorology and geophysics. In this paper we will concentrate on his studiesof the Earth's magnetic field. With his unique observations at the polarstation Gj?ahavn (geographic coordinates 68°37'10'' N; 95°53'25'' W),Amundsen was first to demonstrate, without doubt, that the northmagnetic dip-pole does not have a permanent location, but steadily moves itsposition in a regular manner. In addition, his carefully calibratedmeasurements at high latitudes were the first and only observations of theEarth's magnetic field in the polar regions for decades until modern polarobservatories were established. After a short review of earlier measurementsof the geomagnetic field, we tabulate the facts regarding his measurementsat the observatories and the eight field stations associated with theGj?a expedition. The quality of his magnetic observations may be seen tobe equal to that of the late 20th century observations by subjectingthem to analytical techniques showing the newly discovered relationshipbetween the diurnal variation of high latitude magnetic observations and thedirection of the horizontal component of the interplanetary magnetic field(IMF B_y). Indeed, the observations at Gj?ahavn offer a glimpse of thecharacter of the solar wind 50 yr before it was known to exist. Ourmotivation for this paper is to illuminate the contributions of Amundsen asa scientist and to celebrate his attainment of the South Pole as anexplorer 100 yr ago.