Alfred Wegener

Alfred Lothar Wegener (Berlin, November 1, 1880 – Greenland, November 2 or 3, 1930) was a German interdisciplinary scientist, who became famous for his theory of continental drift.

Career

Wegener had early training in astronomy (Ph.D., University of Berlin, 1904). He became interested in the new discipline of meteorology (he married the daughter of famous meterologist and climatologist Wladimir Köppen) and as a record-holding balloonist himself, pioneered the use of weather balloons to track air masses. His lectures became a standard textbook in meteorology, The Thermodynamics of the Atmosphere. Wegener was part of several expeditions to Greenland to study polar air circulation, when the existence of a jet stream itself was highly controversial. He died there of exposure.

Continental Drift

Browsing the library at the University of Marburg, where he was teaching in 1911, Wegener was struck by the occurrence of identical fossils in geological strata that are now separated by oceans. The accepted explanations or theories at the time posited land bridges to explain away these anomalies. But Wegener was increasingly convinced that the continents themselves had shifted away from a primal single massive supercontinent, which drifted apart about 200 million years ago, to judge from the fossil evidence. From 1912 he publicly advocated his theory of "continental drift", arguing that the continents on both sides of the Atlantic Ocean were drifting apart.

Recovery from a war wound gave Wegener time to think. In 1915, in The Origin of Continents and Oceans (Die Entstehung der Kontinente und Ozeane), Wegener published the theory that there had once been a giant supercontinent, which he named "Pangaea" (meaning "all-Earth") and drew together evidence from various fields. Expanded editions during the 1920s presented the accumulating evidence. The last edition, just before his untimely death, revealed the significant observation that shallower oceans were geologically younger.

Reaction

The one American edition, published in 1924, provoked such hostility that it was not revised. Many geologists focused on a lack of a demonstrable mechanism and rejected and ridiculed Wegener for his ideas, noting that he could not explain how continents were able to move. The theory received support through the controversial years from South African geologist Alexander Du Toit as well as from Arthur Holmes. Only after the mid-20th century discovery of seafloor spreading did Wegener receive credit, as an early developer of the theory of plate tectonics. It took more than 50 years before adequate evidence was acquired and presented to convince mainstream geologists to acknowledge that the continents were actually in motion; and the fit between the coasts of Africa and South America was more than just illusionary. Nevertheless, Wegener's assumed drift rate was ten to a hundred times faster than we now know to be true, and this unreasonable estimate must have contributed to the resistance to his ideas. To quote course materials from Prof. Michael Jordan of Texas A&M University, ^*, " Also, our measurements show the rates of plate movements (about as fast as one's fingernails grow) to be at most about 1/10 to 1/100 of what Wegener had proposed."

Awards and honors

The Alfred Wegener Institute for Polar and Marine Research in Bremerhaven, Germany, established in 1980, honours his name. The Wegener impact craters on both Mars and the Moon, as well as the asteroid 29227 Wegener, are named after him.

External links

1880 births | 1930 deaths | Meteorologists | German geologists | Plate tectonics

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Career

Continental Drift

Reaction

Awards and honors

See also

External links