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Alfred Lothar Wegener (1 November 1880 – November 1930) was a Germanmarker scientist, geophysicist, and meteorologist.


He is most notable for his theory of continental drift (Kontinentalverschiebung), proposed in 1915, which hypothesized that the continents were slowly drifting around the Earth. However, Wegener was unable to demonstrate a mechanism for continental drift, which, combined with his mostly circumstantial evidence, meant that his hypothesis was not accepted until the 1950s, when numerous discoveries provided evidence of continental drift.Spaulding, Nancy E., and Samuel N. Namowitz. Earth Science. Boston: McDougal Littell, 2005.

Biography

Alfred Wegener was born in Berlinmarker during the time of the German Empiremarker, November 1,1880.

Career

Wegener had early training in astronomy and biology. In 1905, he earned his Ph.D. in astronomy from the University of Berlinmarker. However Wegener was always interested in the developing fields of meteorology and climatology. He was a record-holding balloonist (flying a balloon in the air for 52 hours straight) and pioneered the use of weather balloons to track air masses. His lectures, The Thermodynamics of the Atmosphere, became a standard textbook in meteorology. Wegener was involved in several expeditions to Greenlandmarker to study polar air circulation before the existence of the jet stream was accepted. He along with J.P. Koch were the first to winter on the inland ice in a hut they built on the ice in Northeast Greenland. Inside the hut they drilled to a depth of 25 m with an auger.
In 1930, his last expedition was to Greenland to conduct the first 12-month monitoring of arctic weather. Wegener felt responsible for the expeditions success as the German governmentmarker contributed $120,000 ($1.5 million in 2007 dollars) at a time when Germans were starving to death due to post war shortages. This success depended on enough provisions being transferred from West camp to Eismittemarker ("mid-ice") for two men to winter there and was a factor in the decision that led to his death. Due to a late thaw the expedition was six weeks behind schedule and as summer ended the men at Eismitte sent a message that they had insufficient fuel so would return on October 20.

On September 24, although the route markers were by now largely buried by snow, Wegener set out with thirteen Greenlanders and his meteorologist Fritz Loewe to supply the camp by dog sled. During the journey the temperature reached and Loewe's toes became so frostbitten they had to be amputated with a penknife without anaesthetic. Twelve of the Greenlanders returned to West camp. On October 19. the remaining three members of the expedition reached Eismitte.

With only enough supplies for three at Eismitte, Wegener and Rasmus Villumsen took two dog sleds and made for West camp. They took no food for the dogs and culled them to feed the rest until they could only run one sled. While Villumsen rode the sled, Wegener had to use skis. They never reached the camp.

Death

Six months later on May 12, 1931, Wegener's body was found in Greenland buried with great care. A pair of skis marked the grave site. He was found halfway between Eismitte and West camp. At 50 years of age and a heavy smoker his suspected cause of death was heart failure through overexertion. Wegener's body was reburied in the same spot by the team that found the burial site and marked with a large cross.Villumsen departed after burying Wegener to the West camp, but never arrived. The 23 year old's body was never found. It is estimated that due to accumulation of ice, the body now lies at a depth of more than .

Continental drift

Alfred Wegener first thought of this idea by noticing that the different large landmasses of the Earth almost fit together like a jigsaw. America fit closely to Africa and Europe, and Antarctica, Australia, India and Madagascar fitted next to the tip of Southern Africa. Wegener proposed this in 1912, but it wasn't considered to be sufficient evidence in itself. He analysed either side of the Atlantic Oceanmarker for rock type, geological structures and fossils. He noticed that there was a significant similarity.

From 1912, Wegener 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 continent, 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.

Wegener in Greenland, 1930 expedition.


Reaction

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 Englandmarker, the hypothesis was generally met with skepticism. The one American edition of Wegener's work, published in 1925, 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 Leipzigermarker geologist Franz Kossmat, argue that the oceanic crust was too firm for the continents to "simply plow through". In 1943 George Gaylord Simpson wrote a vehement attack on the theory (as well as the rival theory of sunken land bridges) and put forward his own permanentist views . Alexander du Toit wrote a rejoinder in the following year, but G.G.Simpson's influence was so powerful that even in countries previously sympathetic towards continental drift, like Australia, Wegener's hypothesis fell out of favour.

In the early 1950s, the new science of paleomagnetism pioneered at Cambridge Universitymarker by S. K. Runcorn and at Imperial Collegemarker by P.M.S. Blackett was soon throwing up data in favour of Wegener's theory. By early 1953 samples taken from India showed that the country had previously been in the Southern hemisphere as predicted by Wegener. By 1959, the theory had enough supporting data that minds were starting to change, particularly in the United Kingdommarker where, in 1964, the Royal Society held a symposium on the subject.

Additionally, the 1960s saw 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.

Awards and honors

The Alfred Wegener Institute for Polar and Marine Research in Bremerhavenmarker, Germany, was established in 1980 on his centenary. It awards the Wegener Medal in his name. The crater Wegener on the Moon and the crater Wegener on Mars, as well as the asteroid 29227 Wegener and the peninsula where he died in Greenland (Wegener Peninsula near Ummannaq, ), are named after him.

The European Geosciences Union sponsors an Alfred Wegener Medal & Honorary Membership "for scientists who have achieved exceptional international standing in atmospheric, hydrological or ocean sciences, defined in their widest senses, for their merit and their scientific achievements."

References

  1. G.G. Simpson, "Mammals and the Nature of Continents", American Journal of Science 241 (1943):1-31
  2. A. du Toit, "Tertiary Mammals and Continental Drift", American Journal of Science 242 (1944): 145-63
  3. H. Frankel, "The Continental Drift", in "Scientific Controversies: Case Solutions in the resolution and closure of disputes in science and technology", ed. H.T. Engelhardt Jr and A.L. Caplan, Cambridge University Press (1987)
  4. http://www.awi.de/fileadmin/user_upload/News/Print_Products/PDF/252-265_Kap12.pdf Alfred Wegener Institute, 2005 Annual report, page 259
  5. JPL Small-Body Database Browser


Further reading

  • - (Translated from the fourth revised German edition by John Biram)
  • - (Translated from the fourth German edition by John Biram with an introduction by B.C. King)
  • - (Translated from the seventh German edition by Winifred M. Deans)
  • - (Wegener's Thermodynamics of the Atmosphere)


External links




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