Alfred Wegener

1880–1930

Alfred Wegener (1880–1930) first developed the theory that the continental land masses are constantly in motion, a theory now recognized as the most important and far-reaching development in the history of geology.

FOR THOUSANDS OF YEARS, PEOPLE BELIEVED THAT THE DIVISION OF LAND AND SEA was fixed and unchangeable. When Wegener suggested that this was not the case – that the hottest deserts had once been under the polar ice caps, and the countries differently distributed around the world – he struggled to get anyone to take him seriously.

Wegener was convinced that the moving continents were part of a mechanism that explained all the large-scale activity of the Earth, including volcanoes, earthquakes, mountain-building and the movement of the magnetic poles. In this, he was finally proved right, but only long after his death. Trained in astronomy, and a meteorologist by profession, he drew from many disciplines to piece together evidence for his theory. But he was dismissed as an amateur, young and arrogant, propounding dangerous ideas.

Alfred Lothar Wegener was born on 1 November 1880 in Berlin, Germany. He was the youngest child of Dr Richard Wegener, an evangelical minister who ran an orphanage. From his early years, Wegener was fascinated by Greenland, later to become the arena of his most important work on meteorology and, finally, the scene of his death. He learned to ski and skate and trained vigorously during his youth, hoping one day to become a polar explorer.

Weather man

Wegener went to university in Berlin and achieved a PhD in astronomy in 1904, but quickly became interested in the new science of meteorology. Like his brother Kurt, Wegener took a job at the Royal Prussian Aeronautical Observatory near Berlin and soon made a name for himself. He used kites and balloons to study conditions in the upper atmosphere, and he and Kurt even broke a world record by staying aloft in a hot-air balloon for more than 52 hours.

In 1906 Wegener was delighted to be invited to join an expedition to the unmapped eastern coast of Greenland to study polar air flows. At last he could fulfil his dream to explore the polar wasteland. He became the first person to use kites and tethered balloons to study atmospheric conditions over the ice cap.

On his return to Germany he became a lecturer at the University of Marburg where staff and students alike were impressed by the clarity with which he could talk on even the most difficult subjects. He was known for quickly grasping new concepts, integrating them seamlessly with what he knew already and seeing intuitively the answers to complicated problems. Yet despite being a rising star in the meteorological world, it was not in weather studies that he was to make his greatest impact.

The meeting of the North American tectonic plate and the European tectonic plate can be clearly seen near Pingvellir, Iceland, where ravines and cliffs mark the line of the Atlantic Fault. To the left of the picture is the eastern edge of the North American continental plate; to the right, the western edge of Europe.

Shifting continents

Wegener had begun thinking about the shapes of the continents early in his career. In December 1910 he wrote to the woman he would later marry: ‘Doesn’t the east coast of South America fit exactly against the west coast of Africa, as if they had once been joined? This is an idea I’ll have to pursue.’ Pursue it he did, and soon found evidence in the fossil record to encourage him.

In the autumn of 1911, Wegener came across a paper in the university library that listed fossils of plants and animals that are found on both sides of the Atlantic Ocean. He was intrigued, and set about finding more. At the time, scientists explained the similarities by suggesting that land bridges had once spanned the oceans but that these had sunk without trace as the Earth cooled and contracted. Wegener was not convinced by this argument. He suggested instead that there had once been a single, vast continent that had split up and the sections had drifted apart. He called this prehistoric continent Pangea, from the Greek ‘all Earth’. Wegener found his theory immediately compelling. He wrote, ‘A conviction of the fundamental soundness of the idea took root in my mind.’

He first presented his ideas at a meeting of the Geological Association in Frankfurt in January 1912, explaining to a startled audience how he saw the continents moving apart as the sea between them widened. He was quite aware that his theory required overturning all existing understanding of the history of the Earth.

The same year as he first presented his ideas on continental drift, Wegener set off to Greenland again. It was to be a dangerous trip, the four-man team only narrowly escaping death when a glacier they were scaling split beneath them. They became the first people to overwinter on the polar ice cap, and in the following spring made the longest journey over the ice sheet ever made, crossing 750 miles of snow and scaling icy peaks up to 10,000 feet high. The data that Wegener collected, and the work he did with it on his return to Germany, earned him respect as a world expert on polar meteorology and glaciology.

Back in Germany, Wegener married Else Köppen, daughter of the great meteorologist W. P. Köppen, and carried on working on his theory of continent drift. When Wegener first published his theory as The Origin of Continents and Oceans in 1915 it did not have the impact he had hoped for. The First World War had started, and though Wegener himself was quickly discharged from armed service after he was wounded, his theory went unnoticed outside Germany – the world was busy.

The Origin of Continents and Oceans

Wegener proposed that the continental land masses, instead of being rooted deep in the Earth, are moving over it. Rock under the ocean is principally basalt, a denser rock than the granite which makes up the continents. He saw the land masses floating on this, rather like ice floats on the sea, though considerably slowed by the density of the rock they are forcing their way through: land masses ploughing through the oceanic crust like an icebreaker through a frozen sea. At the start of Earth’s history, he thought, there was just a single large continent, which began to break up 200 million years ago, and the parts are still moving. Mountain ranges have been produced where one moving land mass crashes into another, pushing the rocks together and forcing them upwards in folds.

Controversy and conflict

It was not until 1922, when a third edition of his book was translated into several languages, including English, French and Spanish, that it attracted international attention. The response was not encouraging; the book was almost universally reviled, especially in the USA. The president of the American Philosophical Society summed up the general feeling, calling Wegener’s theory ‘Utter, damned rot!’

Wegener was invited to talk in New York about his theory, but met only hostility. Opponents were often downright rude, considering him an amateur in the field of geology, a man arrogantly straying outside his own area of expertise to tell them what to think.

It did not help Wegener’s case that he had no plausible explanation for how the continents moved around over the surface of the Earth. During the 1920s he proposed that a force he called ‘polflucht’, produced by the Earth’s spinning, caused land to pushed away from the poles. This, and some kind of tidal forces, might propel the continents on their course, he suggested. It was not convincing, even to Wegener. One opponent calculated that a tidal force strong enough to move continents would stop the Earth rotating within a year.

A few scientists supported Wegener’s ideas. The Swiss geologist Émile Argand accepted the idea of colliding landmasses as a good explanation for the buckled, distorted strata he found in his studies of the Alps. South African geologist Alexander Du Toit was happy to believe that the similar fossils found in Africa and South America had been deposited when the land masses were adjacent. Helpfully, Alfred Holmes, a professor at Edinburgh University, suggested that convection currents deep within the Earth might move the continents, a theory Wegener included in his 1929 edition of the book and which is now generally accepted. For the majority, though, it was an absurd idea supported by little real evidence and with nothing to recommend it over existing theories.

For such a radical theory to be generally accepted, Wegener knew that he would need a lot of supporting evidence. He looked for this in different disciplines, studying geological features on both sides of the Atlantic as well as the fossil record. Mapping bands of mountains, and of deposits of coal and minerals, shows continuous strips that run across from one continent to another – from Africa to South America, and from Antarctica through India to Africa, for instance.

Wegener’s most compelling evidence came from paleo-climatology – the study of climate patterns millions of years ago. With the help of Vladimir Köppen, he plotted ancient jungles, ice sheets and deserts on his map of Pangea. It all made sense.

The permo-carboniferous ice age, which occurred 280 million years ago, had previously appeared to show the ice sheet scattered randomly around the world, some of it in the hottest deserts. On Wegener’s map, it centred in one place near the south pole, where Africa, Antarctica, Australia and India once met.

A tragic, heroic end

No German university would appoint Wegener as a professor because of the controversy surrounding his ideas. Luckily, a professorship in meteorology and geophysics was created for him in 1924 in the small university of Graz, Austria.

From Graz he continued to work on polar weather, and returned to Greenland in 1930. The expedition went badly from the start. When part of his expedition was stranded 250 miles from the coast, Wegener, as leader, had to launch a rescue mission. In the atrocious conditions, most of Wegener’s rescue team turned back. It took Wegener and two companions forty days to cross the ice to the stranded camp, in temperatures as low as –58 degrees.

The day after celebrating his fiftieth birthday in 1930, Wegener and Villumsen, his Greenlander helper, set out on the return journey. They never arrived. In the spring, Wegener’s body was found stitched into his sleeping bag and marked by two skis upright in the snow. Villumsen had buried him and gone on, but he had disappeared without trace in the icy wilderness. Wegener’s team erected an ice mausoleum and later a 20 foot iron cross where his body lay. Both have since vanished under the snow and ice.

Wegener’s theory languished after his death. With no champion, only a few enthusiasts kept it alive. Yet in the 1950s new scientific methods made it possible to look at the activity of the Earth’s crust in new ways. Examination of the sea floor (oceanography) and studies of how the magnetic polarity of the Earth has shifted over millions of years (paleomagnetism) began to throw up evidence in support of Wegener’s theory of moving land masses.

Plate tectonics

Modern plate tectonics theory explains the movement of the land masses suggested by Wegener. The top part of the Earth – the crust and top level of the mantle – is divided into seven large and several more small plates. These float on top of the rest of the mantle, which is formed of thick, sticky, liquid rock at a high temperature (magma).

The plates slowly move around the Earth, and their movement accounts for the continental drift Wegener described – though he was wrong to assume only the land plates moved, or that they moved through the oceanic crust. We can now trace the past movement of the plates over millions of years, and have established that the Atlantic Ocean is indeed still growing, though North America is moving away from Europe at only 2.5 cm a year – one hundredth of the rate Wegener suggested.

There is still no consensus as to why the plates move over the asthenosphere, though the favourite theory, proposed by Holmes, is that they are carried by convection currents in the magma beneath. As Wegener said, ‘The Newton of drift theory has not yet appeared. His absence need cause no anxiety; the theory is still young’.