Alfred Wegener was a German geophysicist whose theory of continental drift was to revolutionize the science of geology. He was born in Berlin, the son of an orphanage director.
He gained a doctorate in astronomy in 1905, and for much of his career Wegener worked in meteorology. The following year he joined a Danish expedition to Greenland to study polar air circulation. He spent two years there, and made a further three journeys to Greenland during his lifetime.
Wegener joined the German army at the outbreak of the First
World War, but was injured shortly afterward. During a long period of
convalescence, his attention focused on an issue which had interested
him for several years - the origins of the Earth's continents. Like other
scientists before him, Wegener was intrigued how the coastlines of eastern
South America and western Africa might fit together if the two continents
He speculated that the two continents were once joined: furthermore, he proposed that all of the present-day continents originally formed one landmass, which he called Pangaea (meaning 'all lands' in Greek). Wegener believed that the supercontinent began to break into smaller continents around 200 million years ago.
In 1915, Wegener published his hypothesis in a book entitled The Origin of Continents and Oceans. The idea that the continents might have moved over the course of time was not new: the Dutch cartographer Abraham Ortelius had come to this conclusion in 1596, suggesting that the continents had been ripped apart by earthquakes and floods. However, Wegener's theory was supported by scientific evidence, such as the discovery of fossilized tropical plants beneath the Greenland icecap, and the fact that there were glaciated landscapes in the tropics of Africa and South America.
Unfortunately, Wegener's book met with considerable hostility. Contemporary scientists held the view that continents and oceans held permanent positions on the globe. The key question which Wegener's theory had not addressed convincingly was to account for a force that was sufficiently powerful to move huge masses of rock over enormous distances. The English geophysicist Harold Jeffreys argued, quite correctly, that a mass of solid rock would simply break up if it plowed through the ocean floor.
Despite the rejection of his theory by his peers, Wegener continued to search tenaciously for further evidence to support his ideas until the end of his life. After the First World War, he worked in Hamburg on meteorological research for the German government. In 1924, he fulfilled one of his lifetime's ambitions: after a long and seemingly fruitless search, he gained an academic post as professor of meteorology and geophysics at Graz university in Austria.
In September 1930, Wegener made a final expedition to Greenland, to help establish a weather station to study the jet stream. Despite appalling weather, Wegener insisted on getting to the station, he knew that the researchers working there were in desperate need of supplies. After five weeks, Wegener succeeded in reaching the station. Unfortunately he froze to death on his return journey to base camp, the body only being recovered the following summer.
A year before Wegener's death, the English geologist Arthur Holmes speculated that convection currents in the Earth's mantle might account for continental movement. After the war, Wegener's work gradually gained credence, following studies of the Earth's magnetic field and the discovery of the phenomenon of seafloor spreading. Full acceptance came in the mid-60s, when the theory of plate tectonics provided a mechanism that would account for the movement of the continents.