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El Niño timeline

Through Time

Ice core from glacier 2,200 BC
A massive drought, a possible El Niño, leaves its signature in a glacier on an Andean mountain. Dr. Lonnie Thompson recovered a core from this glacier in 1993, and pinpointed the telltale layer during analysis in his laboratory.

1000 AD
An unusually large El Niño leaves its calling card in the growth rings of trees 6,000 miles apart; tree ring samples gathered in northern Arizona by scientists at the Lamont Doherty Earth Observatory show the same growth patterns as samples retrieved from Santiago, Chile.

Excavated bones from burial pit ca. 1500
Eighty people are sacrificed by the Incas. Dr. Steve Bourget from the University of East Anglia recently excavated the burial pit, and put together the evidence that a frightened populace was trying to appease an angry sea god during a strong El Niño.

Spanish conquistadors in Peru create the first written records of El Niño. Some historians speculate that the ruthless Pizarro, who brought down the Incan empire, might have failed were it not for El Niño bringing rain-and horse fodder-to a normally arid land.

X-ray analysis by Dr. Julia Cole, of coral cores drilled in the Galapagos Islands, shows that 300 years ago, El Niño events were half as frequent as they are today. It is not known why.

The only hurricane ever recorded in Los Angeles strikes on August 23, and obliterates the settlement there. "Proxy" evidence in tree rings and lake sediments also suggests 1835 was an El Niño year.

Anchovies Late 19th century
Peruvian fishermen begin referring to the periodic warming of the sea at Christmas as El Niño, meaning "The Child," or "The Little One." Frequently, the Child chases the fish away—but causes the desert to bloom. The term "El Niño" appears in print for the first time in 1892 in a Peruvian scientific journal.

Massive famine strikes India as the monsoons fail during an El Niño year. Uncounted thousands die directly from starvation, and many more die in the epidemic of cholera and plague that follow.

Sir Gilbert Walker 1904
The head of the Indian Meteorological Service, Sir Gilbert Walker, is asked to find a way to predict monsoon failure. Walker concedes that it may take time, but he begins sorting through weather records, looking for a pattern.

Sir Gilbert finally finds what he has spent two decades searching for. He is able to correlate rainfall in South America with periodic changes in ocean temperatures. He also finds a near-perfect mirror-image connection between barometer readings at stations on Tahiti and Darwin, Australia; as pressure rises in the east, it falls in the west. He coins the term Southern Oscillation to dramatize the ups and downs in this east-west seesaw effect. He also finds linkages between the Asian monsoon season, drought in Australia and parts of Africa, and mild winters in western Canada.

Freida, a western Pacific typhoon, crosses the entire ocean (against what should have been prevailing winds) and slams into Oregon, an event never recorded before or since. Some researchers link the typhoon's strange behavior to upper-atmosphere disturbances rooted in the El Niño-La Niña cycle.

Jacob Bjerknes 1969
Norwegian meteorologist Jacob Bjerknes is the first to see a connection between unusually warm sea-surface temperatures in El Niño and the weak easterlies and heavy rainfall that accompany Southern Oscillation conditions. Ultimately, Bjerknes' discovery leads to the recognition that the warm waters of El Niño and the pressure seesaw of Walker's Southern Oscillation are facets of the same phenomenon, sometimes referred to by the acronym ENSO, or El Niño/Southern Oscillation.

Palms blowing in storm 1982
The most powerful El Niño of the century (until 1997) strikes without warning. Strongly teleconnected to California rainfall, it generates wave after wave of punishing storms which soak the west coast, wash away beaches, create floods and mudslides, while creating mild wet conditions in the midwest and north. Worldwide, El Niño storms do fifteen billion dollars of damage, and cost 2000 people their lives.

TOGA/TAO Buoy 1994
The TOGA/TAO buoy array becomes fully operational in the tropical Pacific Ocean. It is the first real-time instrument for detecting the initial advance of El Niño.

1997 (early)
The top computer model predicts no El Niño. Nevertheless, in March TOGA/TAO detects, and satellites confirm, that an unusually strong El Niño is at the starting gate...

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