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Alfred Lothar Wegener (Berlin, November 1, 1880 – Greenland, November 2 or 3, 1930) was a German interdisciplinary scientist and meteorologist, who became famous for his theory of continental drift ("Kontinentalverschiebung" or "die Verschiebung der Kontinente" in his words).

Contents 1 Career 2 Continental Drift 2.1 Theory of centrifugal force 2.2 Reaction 3 Awards and honors 4 See also 5 References 6 Further reading 7 External links

Wegener had early training in astronomy (Ph.D., University of Berlin, 1904). He became very interested in the new discipline of meteorology (he married the daughter of famous meteorologist 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. On his last expedition, Alfred Wegener and his companion Rasmus Villumsen went missing in November 1930. Wegener's body was found on May 12, 1931. His suspected cause of death was heart failure through overexertion.

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. He then noticed that the continents on a globe fit together like a jigsaw. The accepted explanations or theories at the time posited land bridges to explain these anomalies. But Wegener was increasingly convinced that the continents themselves had shifted away from a primal single massive supercontinent, which drifted apart about 180 million years ago, to judge from the fossil evidence.^[1] Wegener used land features, fossils, and climate as evidence to support his hypothesis of continental drift. Examples of land features such as mountain ranges in Africa and South America lined up; also coal fields on Europe matched up with coal fields in North America. Wegener noticed that fossils from reptiles such as Mesosaurus and Lystrosaurus were found in places that are now separated by oceans. Since neither reptile could have swum great distances, Wegener inferred that these reptiles had once lived on a single landmass that split apart.

From 1912 he publicly advocated the theory of "continental drift", arguing that all the continents were once joined together in a single landmass and have drifted apart.

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, in later editions, he named "Pangaea" (meaning "All-Lands" or "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.

Alfred Wegener also came up with a theory to explain continental drift, although it was in error. His theory of continental drift proposed that centrifugal force moved the heavy continents toward the equator as the Earth spun. He thought that inertia, from centrifugal movement combined with tidal drag on the continents (caused by the gravitational pull of the sun and moon) would account for continental drift.

In his work, Wegener presented a large amount of circumstantial evidence in support of continental drift, but he was unable to come up with a convincing mechanism. Thus, while his ideas attracted a few early supporters such as Alexander Du Toit from South Africa and Arthur Holmes in England, the hypothesis was generally met with skepticism. The one American edition of Wegener's work, published in 1924, was received so poorly that the American Association of Petroleum Geologists organized a symposium specifically in opposition to the continental drift hypothesis. Also its opponents could, as did the Leipziger geologist Franz Kossmat, argue that the oceanic crust was too firm for the continents "simply to plow through". By the 1930's, Wegener's geological work was almost universally dismissed by the scientific community and remained obscure for some thirty years.

In the 1950s and 1960s, several developments in geology, notably the discoveries of seafloor spreading and Wadati-Benioff zones, led to the rapid resurrection of the continental drift hypothesis and its direct descendant, the theory of plate tectonics. Alfred Wegener was quickly recognized as a founding father of one of the major scientific revolutions of the 20th century.

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 and the peninsula where he died in Greenland (Wegener Peninsula near Ummannaq, 71°12′00″N, 51°50′00″W), are named after him.^[2]

1. ^ http://www.ucmp.berkeley.edu/history/wegener.html Alfred Wegener (1880-1930)
2. ^ http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=29227

• USGS biography
• Wegener biography at Pangaea.org
• Alfred Wegener, "The origin of continents and oceans", (translated from the 4th German version by John Biram with an introduction by B.C. King), published by Methuen, London, 1968.

• Wegener, Else, ed.(1939) Greenland journey, the story of Wegener’s German expedition to Greenland in 1930-31 as told by members of the expedition and the leader’s diary; (edited by Else Wegener, with the assistance of Dr. Fritz Loewe. Translated from the 7th German edition by Winifred M. Deans). London, Glasgow, Blackie & son ltd.

• Wegener Institute website (English)

Persondata
NAME	Wegener, Alfred Lothar
ALTERNATIVE NAMES
SHORT DESCRIPTION	Interdisciplinary scientist and creator of the theory of continental drift
DATE OF BIRTH	November 1, 1880
PLACE OF BIRTH	Berlin, Germany
DATE OF DEATH	November 2 or 3, 1930
PLACE OF DEATH	Greenland