Alfred Wegener

In a lecture on 6 January 1912 and in his book Die Entstehung der Kontinente und Ozeane (first edition 1915, fourth 1929), Wegener proposed that the continents were once joined and had drifted apart, arguing from the fit of coastlines, matching fossils and rock structures, and past climates. Most geologists rejected the idea, partly because he could not name a force that moves continents; after sea-floor spreading was found around 1960, continental motion was accepted within plate tectonics.

Wegener took part in four Greenland expeditions. On the Danmark expedition (1906-08) he made the first systematic soundings of the polar atmosphere with kites and tethered balloons; in 1912-13 he crossed the ice sheet with J. P. Koch's party; and the 1929 pre-expedition he led made the first reflection-seismic ice-thickness measurements. He led the 1930-31 German expedition, planned as three stations across the ice sheet, and died on it in November 1930; historians describe its programme as a reference for later international expeditions.

Wegener worked as a meteorologist on the upper atmosphere: in 1906 he and his brother Kurt set a balloon world record of about 52 hours aloft, and his 1911 textbook Thermodynamik der Atmosphäre became, according to NASA, a standard text in Germany. With his father-in-law Wladimir Köppen he wrote Die Klimate der geologischen Vorzeit (1924), which the Neue Deutsche Biographie says founded modern palaeoclimatology.

In winter 1918/19 Wegener ran impact experiments in Marburg to simulate lunar craters, and in his 1921 book he argued, against the then-prevailing view, that they were impact scars. In September 1927 he carried out a measurement campaign at the Sall (Kaali) crater on the Estonian island of Saaremaa; according to the Neue Deutsche Biographie, the find of extraterrestrial iron there by Ivan Reinwald then settled that it was an impact crater.

The sequence of a laboratory model and then a field measurement campaign is consistent with the profile's experimentation score: a contested idea was tested by physical means rather than argued only in print. Experimentation

By September 1930 the German Greenland expedition was about 38 days behind schedule and had brought only part of the supplies to the Eismitte station in the centre of the ice sheet. On 21 September Wegener set out from the west coast with Fritz Loewe and 13 Greenlanders to take supplies there; most of the Greenlanders turned back, and Wegener, Loewe and Rasmus Villumsen reached Eismitte on 30 October. On 1 November, his 50th birthday, Wegener started back with Villumsen. He died on the way, probably in mid-November, and a search party found his grave on 12 May 1931.

Choosing to lead a late-season supply convoy himself illustrates the moderate willingness to accept physical risk in this profile. It is one reading among others: a 2000 historical study of the expedition concludes that several people, not only the leader, made erroneous judgements and that no single person can be blamed. Risk Tolerance

On 6 January 1912 Wegener, a 31-year-old meteorologist and lecturer at Marburg, presented his drift hypothesis to the Geologische Vereinigung in Frankfurt, although his father-in-law Wladimir Köppen had warned him against entering geology as an outsider. A second lecture followed in Marburg four days later and a long paper appeared in Petermanns Mitteilungen from April; he returned to the theme in book editions of 1915, 1920, 1922 and 1929. From then on his name was tied to a controversial geological question, not only to meteorology and polar research.

Presenting the idea to specialists in a field that was not his own, after a warning from his mentor, is consistent with the profile's independent thinking score. Independent Thinking