Alfred Wegener
Overview
 
Alfred Lothar Wegener ( – ) was a German scientist
Scientist
A scientist in a broad sense is one engaging in a systematic activity to acquire knowledge. In a more restricted sense, a scientist is an individual who uses the scientific method. The person may be an expert in one or more areas of science. This article focuses on the more restricted use of the word...

, geophysicist, and meteorologist.

He is most notable for his theory of continental drift
Continental drift
Continental drift is the movement of the Earth's continents relative to each other. The hypothesis that continents 'drift' was first put forward by Abraham Ortelius in 1596 and was fully developed by Alfred Wegener in 1912...

 (), proposed in 1912, which hypothesized that the continent
Continent
A continent is one of several very large landmasses on Earth. They are generally identified by convention rather than any strict criteria, with seven regions commonly regarded as continents—they are : Asia, Africa, North America, South America, Antarctica, Europe, and Australia.Plate tectonics is...

s were slowly drifting around the Earth. However, his hypothesis was not accepted until the 1950s, when numerous discoveries such as palaeomagnetism confirmed his hypothesis of continental drift.
On November 1, 1880, Alfred Wegener was born in Berlin during the time of the German Empire
German Empire
The German Empire refers to Germany during the "Second Reich" period from the unification of Germany and proclamation of Wilhelm I as German Emperor on 18 January 1871, to 1918, when it became a federal republic after defeat in World War I and the abdication of the Emperor, Wilhelm II.The German...

.
Wegener attended the in his home town.
Encyclopedia
Alfred Lothar Wegener ( – ) was a German scientist
Scientist
A scientist in a broad sense is one engaging in a systematic activity to acquire knowledge. In a more restricted sense, a scientist is an individual who uses the scientific method. The person may be an expert in one or more areas of science. This article focuses on the more restricted use of the word...

, geophysicist, and meteorologist.

He is most notable for his theory of continental drift
Continental drift
Continental drift is the movement of the Earth's continents relative to each other. The hypothesis that continents 'drift' was first put forward by Abraham Ortelius in 1596 and was fully developed by Alfred Wegener in 1912...

 (), proposed in 1912, which hypothesized that the continent
Continent
A continent is one of several very large landmasses on Earth. They are generally identified by convention rather than any strict criteria, with seven regions commonly regarded as continents—they are : Asia, Africa, North America, South America, Antarctica, Europe, and Australia.Plate tectonics is...

s were slowly drifting around the Earth. However, his hypothesis was not accepted until the 1950s, when numerous discoveries such as palaeomagnetism confirmed his hypothesis of continental drift.

Biography

On November 1, 1880, Alfred Wegener was born in Berlin during the time of the German Empire
German Empire
The German Empire refers to Germany during the "Second Reich" period from the unification of Germany and proclamation of Wilhelm I as German Emperor on 18 January 1871, to 1918, when it became a federal republic after defeat in World War I and the abdication of the Emperor, Wilhelm II.The German...

.

Career

Wegener attended the in his home town. After he had finished school he studied physics, astronomy and meteorology at the (today Humboldt University), Berlin. In 1905, he earned his Ph.D.
Doctor of Philosophy
Doctor of Philosophy, abbreviated as Ph.D., PhD, D.Phil., or DPhil , in English-speaking countries, is a postgraduate academic degree awarded by universities...

 in astronomy
Astronomy
Astronomy is a natural science that deals with the study of celestial objects and phenomena that originate outside the atmosphere of Earth...

 under the direction of Julius Bauschinger
Julius Bauschinger
-Biography:Julius Bauschinger was born in Fürth, the son of the physicist Johann Bauschinger. He studied at the Universities of Munich and Berlin, graduating under the direction of Hugo Hans von Seeliger with a thesis titled "Studies on the motion of the planet Mercury"...

. However Wegener was always interested in the developing fields of meteorology
Meteorology
Meteorology is the interdisciplinary scientific study of the atmosphere. Studies in the field stretch back millennia, though significant progress in meteorology did not occur until the 18th century. The 19th century saw breakthroughs occur after observing networks developed across several countries...

 and climatology
Climatology
Climatology is the study of climate, scientifically defined as weather conditions averaged over a period of time, and is a branch of the atmospheric sciences...

. He was a record-holding balloonist
Balloon (aircraft)
A balloon is a type of aircraft that remains aloft due to its buoyancy. A balloon travels by moving with the wind. It is distinct from an airship, which is a buoyant aircraft that can be propelled through the air in a controlled manner....

 (flying a balloon continuously for 52 hours) and pioneered the use of weather balloon
Weather balloon
A weather or sounding balloon is a balloon which carries instruments aloft to send back information on atmospheric pressure, temperature, humidity and wind speed by means of a small, expendable measuring device called a radiosonde...

s to track air mass
Air mass
In meteorology, an air mass is a volume of air defined by its temperature and water vapor content. Air masses cover many hundreds or thousands of square miles, and adopt the characteristics of the surface below them. They are classified according to latitude and their continental or maritime...

es. His lectures, The Thermodynamics of the Atmosphere, became a standard textbook in meteorology. Wegener was involved in several expeditions to Greenland
Greenland
Greenland is an autonomous country within the Kingdom of Denmark, located between the Arctic and Atlantic Oceans, east of the Canadian Arctic Archipelago. Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe for...

 to study polar
Geographical pole
A geographical pole is either of the two points—the north pole and the south pole—on the surface of a rotating planet where the axis of rotation meets the surface of the body...

 air circulation before the existence of the jet stream
Jet stream
Jet streams are fast flowing, narrow air currents found in the atmospheres of some planets, including Earth. The main jet streams are located near the tropopause, the transition between the troposphere and the stratosphere . The major jet streams on Earth are westerly winds...

 was accepted. He and J.P. Koch were the first to winter the inland ice in Northeast Greenland. Inside the hut they drilled to a depth of 25 m with an auger.

Last expedition

In 1930, his last expedition was to Greenland to conduct the first 12-month monitoring of arctic weather. Wegener felt responsible for the expedition's success, as the German government
Weimar Republic
The Weimar Republic is the name given by historians to the parliamentary republic established in 1919 in Germany to replace the imperial form of government...

 had 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 ("mid-ice") for two men to winter there, which 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 sent a message that they had insufficient fuel, and 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 -60 °C and Loewe's toes became so frostbitten they had to be amputated with a penknife without anesthetic. Twelve of the Greenlanders returned to West camp. On October 19, the remaining three members of the expedition reached . With only enough supplies for three at , Wegener and Rasmus Villumsen took two dog sleds and made for West camp. They took no food for the dogs and killed 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, halfway between and West camp, buried with great care. A pair of skis marked the grave site. At 50 years of age and a heavy smoker, Wegener's suspected cause of death was heart failure through overexertion. His body was reburied in the same spot by the team that found the burial site and marked with a large cross. After burying Wegener, Villumsen departed for the West camp, but was never seen again. It is estimated that the 23-year-old's body now lies buried under more than 100 metres (328.1 ft) of accumulated ice and snow.

Continental drift theory

Alfred Wegener first thought of this idea by noticing that the different large landmasses of the Earth almost fit together like a jigsaw. The Continental shelf
Continental shelf
The continental shelf is the extended perimeter of each continent and associated coastal plain. Much of the shelf was exposed during glacial periods, but is now submerged under relatively shallow seas and gulfs, and was similarly submerged during other interglacial periods. The continental margin,...

 of the Americas fit closely to Africa and Europe, and Antarctica, Australia, India and Madagascar fit next to the tip of Southern Africa. But Wegener only took action after reading a paper in Autumn 1911 and seeing that a flooded land-bridge contradicts isostasy
Isostasy
Isostasy is a term used in geology to refer to the state of gravitational equilibrium between the earth's lithosphere and asthenosphere such that the tectonic plates "float" at an elevation which depends on their thickness and density. This concept is invoked to explain how different topographic...

. Wegener's main interest was meteorology, and he wanted to join the Denmark-Greenland expedition scheduled for mid 1912. So he hurried up to present his Continental Drift hypothesis on 6 January 1912. He analyzed either side of the Atlantic Ocean for rock type, geological structures and fossils. He noticed that there was a significant similarity between matching sides of the continents, especially in fossil plants. His hypothesis was thus strongly supported by the physical evidence, and was a pioneering attempt at a rational explanation.
From 1912, Wegener publicly advocated the theory of "continental drift
Continental drift
Continental drift is the movement of the Earth's continents relative to each other. The hypothesis that continents 'drift' was first put forward by Abraham Ortelius in 1596 and was fully developed by Alfred Wegener in 1912...

", arguing that all the continents were once joined together in a single landmass and have drifted apart. He supposed the cause might be the centrifugal force of the Earth's rotation ("") or the astronomical precession
Precession
Precession is a change in the orientation of the rotation axis of a rotating body. It can be defined as a change in direction of the rotation axis in which the second Euler angle is constant...

. Wegener also speculated on sea-floor spreading and the role of the mid-ocean ridge
Mid-ocean ridge
A mid-ocean ridge is a general term for an underwater mountain system that consists of various mountain ranges , typically having a valley known as a rift running along its spine, formed by plate tectonics. This type of oceanic ridge is characteristic of what is known as an oceanic spreading...

s, stating: the Mid-Atlantic Ridge ... zone in which the floor of the Atlantic, as it keeps spreading, is continuously tearing open and making space for fresh, relatively fluid and hot sima [rising] from depth. However, he did not pursue these ideas in his later works.

In 1915, in The Origin of Continents and Oceans (), Wegener published the theory that there had once been a giant continent, he named "" (German word meaning "origin of the continents", in a way equivalent to the Greek "Pangaea
Pangaea
Pangaea, Pangæa, or Pangea is hypothesized as a supercontinent that existed during the Paleozoic and Mesozoic eras about 250 million years ago, before the component continents were separated into their current configuration....

", 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.

Reaction

In his work, Wegener presented a large amount of very strong evidence in support of continental drift, but the mechanism remained elusive. While his ideas attracted a few early supporters such as Alexander Du Toit
Alexander Du Toit
Alexander Logie du Toit was a geologist from South Africa, and an early supporter of Alfred Wegener's theory of continental drift.Born in Newlands, Cape Town in 1878, du Toit was educated at the Diocesan College in Rondebosch and the University of the Cape of Good Hope...

 from South Africa and Arthur Holmes
Arthur Holmes
Arthur Holmes was a British geologist. As a child he lived in Low Fell, Gateshead and attended the Gateshead Higher Grade School .-Age of the earth:...

 in England, the hypothesis was generally met with skepticism from largely conservative scientists, who were resistant to any change in the status quo. The one American edition of Wegener's work, published in 1925, was received so poorly that the American Association of Petroleum Geologists
American Association of Petroleum Geologists
The American Association of Petroleum Geologists is one of the world's largest professional geological societies with over 31,000 members as of 2007. The AAPG works to advance the science of geology , to promote technology, and to inspire high professional conduct...

 organized a symposium specifically in opposition to the continental drift hypothesis. Its opponents could argue, as did the Leipzig
Leipzig
Leipzig Leipzig has always been a trade city, situated during the time of the Holy Roman Empire at the intersection of the Via Regia and Via Imperii, two important trade routes. At one time, Leipzig was one of the major European centres of learning and culture in fields such as music and publishing...

er geologist Franz Kossmat
Franz Kossmat
Franz Kossmat was an Austrian-German geologist, for twenty years the director of the Geological Survey of Saxony under both the kingdom and the subsequent German Republic....

, that the oceanic crust was too "firm" for the continents to "simply plough through", a suggestion which ignored the plasticity
Plasticity
Plasticity may refer to:Science* Plasticity , in physics and engineering, plasticity is the propensity of a material to undergo permanent deformation under load...

 of all rocks at depth and at high temperatures and pressures. The comment also ignored the vast time-scale over which continental drift has occurred, effectively the total age of the earth
Age of the Earth
The age of the Earth is 4.54 billion years This age is based on evidence from radiometric age dating of meteorite material and is consistent with the ages of the oldest-known terrestrial and lunar samples...

 of about 4.5 billion years.

In 1943 George Gaylord Simpson
George Gaylord Simpson
George Gaylord Simpson was an American paleontologist. Simpson was perhaps the most influential paleontologist of the twentieth century, and a major participant in the modern evolutionary synthesis, contributing Tempo and mode in evolution , The meaning of evolution and The major features of...

 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.

Modern developments

In the early 1950s, the new science of paleomagnetism
Paleomagnetism
Paleomagnetism is the study of the record of the Earth's magnetic field in rocks. Certain minerals in rocks lock-in a record of the direction and intensity of the magnetic field when they form. This record provides information on the past behavior of Earth's magnetic field and the past location of...

 pioneered at Cambridge University by S. K. Runcorn and at Imperial College by P.M.S. Blackett was soon producing 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 Kingdom 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
Seafloor spreading
Seafloor spreading is a process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge. Seafloor spreading helps explain continental drift in the theory of plate tectonics....

 and Wadati-Benioff zones, led to the rapid resurrection of the continental drift hypothesis and its direct descendant, the theory of plate tectonics
Plate tectonics
Plate tectonics is a scientific theory that describes the large scale motions of Earth's lithosphere...

. Alfred Wegener was quickly recognized as the founding father of one of the major scientific revolutions of the 20th century.

With the advent of the Global Positioning System
Global Positioning System
The Global Positioning System is a space-based global navigation satellite system that provides location and time information in all weather, anywhere on or near the Earth, where there is an unobstructed line of sight to four or more GPS satellites...

 (GPS), it became possible to measure continental drift directly.

Awards and honors

The Alfred Wegener Institute for Polar and Marine Research
Alfred Wegener Institute for Polar and Marine Research
The Alfred Wegener Institute of Polar and Marine Research is a scientific organization located in Bremerhaven, Germany. The institute was founded in 1980 and is named after revolutionary meteorologist climatologist, and geologist Alfred Wegener...

 in Bremerhaven
Bremerhaven
Bremerhaven is a city at the seaport of the free city-state of Bremen, a state of the Federal Republic of Germany. It forms an enclave in the state of Lower Saxony and is located at the mouth of the River Weser on its eastern bank, opposite the town of Nordenham...

, Germany, was established in 1980 on his centenary. It awards the Wegener Medal in his name. The crater Wegener
Wegener (lunar crater)
Wegener is a lunar impact crater that is located in the Moon's northern hemisphere, about midway between the equator and the north pole. It lies on the far side from the Earth, behind the northwestern limb. The southwestern rim of Wegener iintrudes slightly into the much larger walled plain Landau...

 on the Moon and the crater Wegener on Mars, as well as the asteroid
Asteroid
Asteroids are a class of small Solar System bodies in orbit around the Sun. They have also been called planetoids, especially the larger ones...

 29227 Wegener
29227 Wegener
29227 Wegener is a main-belt asteroid discovered on February 29, 1992 by F. Borngen at Tautenburg.- External links :*...

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

The European Geosciences Union
European Geosciences Union
The European Geosciences Union is an interdisciplinary non-profit learned society open to individuals who are professionally engaged in or associated with geosciences, planetary and space sciences, and related studies.The mission statement of the EGU is "Dedicated to the pursuit of excellence in...

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."

Selected works

|trans_title=Thermodynamics of the Atmosphere |year=1911 |location=Leipzig |publisher= |language=German |url=http://books.google.com/?id=slxDAAAAIAAJ&pg=PR1&dq=alfred+wegener}} |journal= |volume=63 |issue= |pages=185–195, 253–256, 305–309 |accessdate= |language=German |postscript=. Presented at the annual meeting of the German Geological Society, Frankfurt am Main (January 6, 1912).}} |journal= |volume=3 |issue=4 |month=July |year=1912 |language=German |doi=10.1007/BF02202896 |pages = 276–292|bibcode = 1912GeoRu...3..276W }} |trans_title=The Origin of Continents and Oceans |language=German |year=1922 |lccn=unk83068007 |isbn=3443010563}} |trans_title=The Origin of Continents and Oceans |edition=4 |year=1929 |publisher= |language=German |location=Braunschweig |isbn=3443010563}}

External links

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