The Weather Scientist Who Said the Continents Move

The listener is a child; the reader is a parent. This page helps you answer the questions your child may ask after the story. You can see the script during playback with the script button.

What this is about

In 1912, a German weather scientist spoke to a room of rock scientists. He said the continents were once one piece. Then they broke apart and slowly moved to where they are now. His name was Alfred Wegener.

The story is often told like this: "a genius saw that South America and Africa fit like a puzzle." This piece changes that a little. He was not the first to see the puzzle shape. What he did was bring loose clues from many fields into one place. And he never claimed he knew what moved the continents.

This piece is part of the set "People who measured the Earth." The others are about Eratosthenes, Inge Lehmann, and the Alvarez father and son. All four are about people who measured something they could never visit, using the traces it left behind. Here, that thing is the Earth of millions of years ago.

What actually happened

• A man of the sky. Wegener was born in Berlin in 1880 (DOI: 10.21638/11701/spbu07.2018.207). He did his PhD in the study of stars, then moved to weather science. He was also a known polar explorer (DOI: 10.1093/oso/9780195393965.003.0016). He taught weather science and star science at the University of Marburg (DOI: 10.1093/oso/9780195165890.003.0003).
• 1912, just over age thirty. On 6 January 1912, he first shared the idea at a rock science meeting in Frankfurt. That same year, he published "Die Entstehung der Kontinente" ("The Origin of the Continents") in a geography journal (DOI: 10.2312/polarforschung.75.1.29). A paper with the same title also came out that year in the journal Geologische Rundschau (DOI: 10.1007/bf02202896).
• Someone told him not to. Wladimir Köppen was a climate scientist. He worked with Wegener and later became his father-in-law. Köppen warned him that a weather scientist, an outsider, should stay out of rock science fights. Wegener spoke anyway (DOI: 10.2312/polarforschung.75.1.29). Later, Köppen became one of the people who defended the idea in print (same DOI).
• The puzzle shape was not his find. Wegener was not the first to notice how Brazil and Africa fit like a key and a lock (DOI: 10.2312/polarforschung.75.1.29). Others had also imagined that land could move. What he did first was gather a large body of evidence from rocks, Earth surveys, and fossils (DOI: 10.1093/oso/9780195188578.003.0002).
• The clues he gathered. Close the Atlantic, and the continents fit like a puzzle. Put them together into one big land, which he called Pangaea, and the "picture" on top matches too. Fossil plants and shallow-sea animals on both sides look alike. Wegener argued they could not have crossed the deep ocean (DOI: 10.1017/cbo9781316048184.002; for the name Pangaea, DOI: 10.1017/cbo9780511842368). He also pointed to marks of old ice ages found on both South America and Africa. And he noted that the Earth's surface sits at two main levels: land at about 100 m above the sea, and sea floor at about 4,700 m below it (DOI: 10.4000/bibnum.500). Today, school books often use the Glossopteris plants and animals like Mesosaurus as examples that the southern continents were once joined (DOI: 10.2475/03.2014.03).
• The book came out four times. The first edition of The Origin of Continents and Oceans came out in 1915. Then came 1920, 1922 (put into English in 1924), and 1929. The last was one year before he died (DOI: 10.1093/oso/9780195117325.003.0009).
• How people reacted. Earth scientists held meetings to attack both his theory and the man himself. Only a handful of rock scientists in Europe and South Africa thought it was worth a closer look (DOI: 10.1093/oso/9780195188578.003.0002). The British rock scientist Philip Lake wrote in a review that Wegener was "quite devoid of critical faculty" (DOI: 10.1093/oso/9780195117325.003.0012). But each country reacted in its own way. Switzerland took up the idea quickly and warmly. The Dutch and the Spanish were also open to it. In Germany, views ran from angry no to eager yes (DOI: 10.17704/eshi.4.2.a747p657926x8j58).
• He was careful about the force. The last chapter of the third edition is about what moves the continents. There, Wegener's tone was clearly more careful than in the rest of the book, and he openly admitted large doubts (DOI: 10.1093/oso/9780195117325.003.0010).
• The last journey (1929–1931). He planned the whole journey from his earlier trips to Greenland. From Copenhagen they shipped 98 tons in 2,500 boxes, bags, and barrels, with 14 men. In Iceland they took on 3 more men and 25 ponies. Wegener checked every detail, as carefully as in his science (DOI: 10.1093/oso/9780195188578.003.0005). The weather station Eismitte sat in the middle of the Greenland ice. It was 400 km from the coast, two weeks away by dog sled in good weather (DOI: 10.1093/oso/9780195188578.003.0006). By mid-September, three sled trips had brought only part of what two men needed for the winter. The engine sleds had stopped before they got there (DOI: 10.1093/oso/9780195188578.003.0007). In early October, morning air at the station fell to −37°C, and the two men dug an ice cave to live in. Wegener arrived there on 30 October (DOI: 10.1093/oso/9780195188578.003.0009). Only after the winter storms calmed did people go out to search for him and Villumsen (DOI: 10.1093/oso/9780195188578.003.0010). He died on the Greenland ice in 1930 (DOI: 10.1017/s0032247400016247).
• His memory, and a later look. In 1931, the Geographical Society of Berlin officially welcomed the team home. A memorial speech there praised his "magnificent conception of his duty as leader." It said he risked his life to rescue his team, and it blamed his death on a chain of bad luck, mostly bad weather. A study in 2000 went back to hidden papers. It pointed to the group that paid for the trip, mistakes in judgment by the leader and some team members, and the lack of radio. It found that no single person can be blamed, even though one team member was made the scapegoat (DOI: 10.1017/s0032247400016247).
• When he died. Nature printed a full-page obituary. It told of his early work in weather science and called his death "a great loss to geophysical science" (DOI: 10.1093/oso/9780195117325.003.0012). One book says that after a 1926 meeting of American oil geologists, most people saw moving continents as a dead issue until the 1960s (DOI: 10.1093/oso/9780195188578.003.0012). But another study argues that the 1926 meeting was not really the turning point (DOI: 10.17704/eshi.14.1.8664862716123568).

Questions your child may ask

"Why didn't people believe him?" The usual answer is that he could not explain the force that moved the continents. This is indeed named as one reason the idea took so long (DOI: 10.4000/bibnum.500). One study says the strongest attacks came from the physics of the Earth (DOI: 10.1080/08912963.2016.1156677). But other research argues against this answer. The historian Naomi Oreskes says American rock scientists did not reject the idea for lack of a cause. She says they rejected it because it seemed to clash with the basic way American rock science was done (DOI: 10.1093/oso/9780195117325.001.0001). You might tell your child: "There was more than one reason, and grown-up scientists still don't agree."

"So what moves the continents?" The story does not explain this. Our sources give us today's picture. The Earth's outer shell is broken into about twenty plates. They move a few centimeters a year. Their motion and crashes cause most volcanoes, earthquakes, and mountain belts (DOI: 10.1038/npg.els.0001632). Sea floor splits at ocean ridges and new floor forms there. Magnetic stripes on the sea floor, lying along the ridges, and deep-sea drilling confirmed this (DOI: 10.1093/actrade/9780198728269.003.0002).

"How did Wegener die?" In 1930, the station in the middle of the Greenland ice was short of winter supplies. He went there himself and never came back. It may matter to your child that "it was not one person's fault." A study of the old papers came to that conclusion (DOI: 10.1017/s0032247400016247).

"Are the continents still moving?" Yes. Today GPS satellites measure it directly. Greenland and North America are moving west, and Europe is moving east (DOI: 10.4000/bibnum.500).

"So was Wegener right?" In the big picture, yes. Rock magnetism studies in the 1950s and plate tectonics in the 1960s took his moving continents into a wider theory (DOI: 10.1093/actrade/9780198728269.003.0001). He was also right that sea floor rock would be very unlike continent rock (DOI: 10.5670/oceanog.2006.06). Still, it is more exact to say that plate tectonics is not Wegener's theory as he wrote it. It is a new theory that holds his idea inside it.

Ideas inside the story

• Measuring by traces. No one can visit the Earth of millions of years ago. So you gather what is left (coastlines, fossils, ice marks) and measure with those. This is the shared method of all four pieces in "People who measured the Earth."
• Bringing loose clues together. What was new about Wegener was not the puzzle shape. It was tying together evidence from many fields.
• Being careful about what you don't know. He called the weakest part of his own theory, the force, weak.

What is evidence and what is story

What our sources state — his birth (1880, Berlin); astronomy PhD, weather scientist, and polar explorer; the 1912 Frankfurt talk and the two journal papers; Köppen's warning; that he was not the first to see the puzzle shape; fossils, ice marks, and the two surface levels; the name Pangaea; the four editions; the attacks and Lake's review; different reactions in each country; the careful chapter on the force; the supplies, ponies, distance, cold, and arrival date of the last journey; the memorial speech and the 2000 study; the Nature obituary; the sea floor mapping after the war and the change in the 1960s; sea floor rock; GPS.

What this piece left out or changed on purpose

• ⚠️ We did not say flatly that "he was rejected because he could not explain the force." That answer has support (DOI: 10.4000/bibnum.500). But a history study argues directly against it (DOI: 10.1093/oso/9780195117325.001.0001). The script gives both sides and ends with "even grown-up scientists still do not agree."
• ⚠️ We did not say how many times he went to Greenland. One source says the last journey drew on "three earlier trips to Greenland" (DOI: 10.1093/oso/9780195188578.003.0005). Another says he took part in "three expeditions" (DOI: 10.5194/egusphere-egu2020-10032). They count in other ways. Perhaps the last journey was counted as two parts, a 1929 first look and the main 1930 trip. So the script only says "more than once."
• We did not say exactly how or where he died. Our sources take us to his arrival at Eismitte on 30 October, his failure to return, and the search that began after the winter storms calmed. The way home, the finding of his body, and the story that it was his birthday are not in the abstracts we found.
• Stories from his youth, such as a long balloon flight, were searched for from several angles. We found no abstract to support them, so we left them out.
• We kept the names of his critics to a minimum. The script names no critic ("one British rock scientist"). Only this page names Lake.

One more thing: craters on the Moon. Soon after the First World War, Wegener did simple but clever experiments. From them, he decided that the Moon's craters were made by things crashing into it. Today, his view and his way of thinking are mostly accepted, along with his once-mocked moving continents (DOI: 10.17704/eshi.17.2.b342311n1w401vv7). This is a good link if your child asks about a photo of the Moon. It also connects to the Alvarez piece in this set, which is about a crash.

Sources and what followed

The original paper — Alfred Wegener, "Die Entstehung der Kontinente," Geologische Rundschau 3(4), 1912 (DOI: 10.1007/bf02202896). The record we found has no abstract, so we checked its content through later works that discuss it.

Main sources

• Alfred Wegener's Hypothesis on Continental Drift and Its Discussion in Petermanns Geographische Mitteilungen (1912–1942). DOI: 10.2312/polarforschung.75.1.29
• The Rejection of Continental Drift (Oreskes, 1999) and its chapters. DOI: 10.1093/oso/9780195117325.001.0001 · 10.1093/oso/9780195117325.003.0009 · 10.1093/oso/9780195117325.003.0010 · 10.1093/oso/9780195117325.003.0012
• Ending in Ice (2006) and its chapters. DOI: 10.1093/oso/9780195188578.003.0002 · 10.1093/oso/9780195188578.003.0005 · 10.1093/oso/9780195188578.003.0006 · 10.1093/oso/9780195188578.003.0007 · 10.1093/oso/9780195188578.003.0009 · 10.1093/oso/9780195188578.003.0010 · 10.1093/oso/9780195188578.003.0012
• Lifting the veil: the circumstances that caused Alfred Wegener's death on the Greenland icecap, 1930. DOI: 10.1017/s0032247400016247
• The Continental Drift Controversy: Wegener and the Early Debate. DOI: 10.1017/cbo9780511842368
• Plate tectonics and why we have earthquakes. DOI: 10.1017/cbo9781316048184.002
• Alfred Wegener et la dérive des continents. DOI: 10.4000/bibnum.500
• The Reaction in Continental Europe to Wegener's Theory of Continental Drift. DOI: 10.17704/eshi.4.2.a747p657926x8j58

What followed

• Work that was not trying to test Wegener brought him back. After the Second World War, sea floor mapping became a priority for the US Navy, to track submarines. It began for reasons that had nothing to do with anything Wegener wrote. But new maps of magnetism, earthquakes, and sea floor shape gave a fresh view of the ocean bottom (DOI: 10.1093/oso/9780195188578.003.0012). In the mid-1960s, rock scientists took up moving continents, or more exactly plate tectonics, "almost literally overnight" (DOI: 10.1086/psaprocbienmeetp.1978.2.192472).
• His name lives on in the polar regions. Germany's Alfred Wegener Institute runs the ice-breaking research ship Polarstern. It studies the icy seas of the far north and far south (DOI: 10.17815/jlsrf-3-163).

Things to try together

• Continent puzzle. Cut the continents out of a world map and fit them together. South America and Africa fit quickly, but other places don't. This leads to the story of why Wegener needed more than coastlines, and collected fossils and ice marks too.
• A clue game. Pick one small mystery at home, like who ate the cookies. Let your child solve it with several clues: crumbs, a wrapper, the time. One clue is weak. Many clues pointing the same way are strong. That was Wegener's method.
• Saying "I'm not sure." When your child explains something, ask them to split it into what they are sure of and what they are not. That is what Wegener did in the last chapter of his book.