Bigger than weather, El Niño a force of history, new book says

August 28, 2001

GAINESVILLE, Fla. — Humans may not be able to change the weather, but the weather has had a powerful effect on the course of major events in human history, according to a University of Florida geographer’s new book on the global weather anomaly known as El Niño.

From the sinking of the Titanic to the German army’s siege of Stalingrad to the ancient discovery and colonization of remote Easter Island, El Niño has played a central — but largely unappreciated — role, writes Cesar Caviedes in the book, “El Niño In History: Storming Through The Ages.” Published by the University Press of Florida, the book is one of the main references for a planned exhibition on the global effects of El Niño at the Smithsonian Institution in Washington, D.C., set for February.

“Much has been studied about El Niño from a strict meteorological perspective, but the book shifts the focus to the impact of El Niño on the environment and on people,” said Caviedes, a UF professor of geography and climatologist. “It turns out El Niño has been a lot more important in shaping some historical events than it usually get credit for.”

Caviedes, who has published extensively on El Niño, said he first began studying the phenomenon’s impact on the Pacific coast of South America in the early 1970s, when only a handful of climatologists and geographers were aware of its importance.

El Niño occurs when winds in the tropical Pacific that normally blow east to west over the equator ease or reverse, causing warming of surface waters in the Eastern Pacific. The phenomenon upsets normal weather patterns worldwide, spurring warmer, wetter winters in the Americas, droughts in parts of Africa and Asia and other climatic anomalies. Its counterpart, La Niña, follows an El Niño event and has the opposite effect, leading, for example, to drier weather on the west coast of the Americas.

Although long recognized in South America – Peruvian fishermen noticed the onset of El Niño around Christmas, whence its name, Spanish for “the Christ Child” – it was little appreciated outside that continent until the 1980s. In 1997, one of the strongest El Niños in recorded history struck, followed by a strong La Niña in 1999-2000. The 1997 El Niño resulted in widespread floods in South America, destructive storms in California and the Southwest, and droughts that caused crop failures and famines in Africa.

Caviedes said the traumatic effects of the 1997 El Niño are only the most pronounced recent manifestations of how El Niños or La Niñas have shaped world events.

Although there are reliable meteorological and oceanic records that permit the identification of El Niño or La Niña dating back a century or so, Caviedes relied on the work of other scientists and his own investigation to detect the occurrence of El Niños before then. He and others have extrapolated those El Niños based on references or indications of environmental changes resembling those that occur during contemporary El Niños, leading to what is considered a credible record of past El Niños and La Niñas dating to the early 1500s.

Caviedes said when he compared the indicators of past El Niños with world historical events he noticed many strong correlations.

For example, 1811 was an El Niño year that transitioned to a La Niña in 1812. Such transitions are marked in Eastern Europe and Russia by bitterly cold winters, he said. As it happens, Napoleon’s army invaded Russia in 1812, just as winter was setting in. Because of the extreme cold, the results were catastrophic for both Napoleon and his troops, with tens of thousands of soldiers dying from exposure and Napoleon forced into an armistice.

Ironically, Hitler made the same mistake more than a century later, Caviedes said. His Sixth Army laid siege to Stalingrad starting in late summer 1942, just when the El Niño of 1940-41 began transitioning into a La Niña year. That fall, cloudy weather, rain and snow hindered German air operations while giving Russian ground troops the opportunity to attack, squeezing the Germans into the infamous 40-by-20-mile “cauldron.” The Sixth Army surrendered in January 1943, signaling the coming decline of the entire German army.

Caviedes ties El Niños and La Niñas to numerous other historic events in his book. For example, the El Niño-La Niña transition is known to lead to frequent calving of icebergs in the southern margins of the Arctic. Such was the scenario in the spring of 1912, when the Titanic set out on its doomed voyage. The abundant snow that Lewis and Clark encountered during their perilous crossing of the Bitterroot mountains, meanwhile, is almost certainly related to the humidity of the Pacific caused by the 1804-1805 El Niño, Caviedes said.

Although it is too far in the past to confirm, Caviedes speculates that El Niño may also explain how settlers from Polynesia reached Easter Island, located more than 1,000 miles from the South Sea islands. Pacific currents that normally flow east to west reverse in El Niño years, which would have enabled the Polynesians to sail east to the island, he said.