Records preserved in corals from Indonesia reveal that El Niño was causing severe weather even before the last ice age began, when the climate apparently was like it was for most of the 20th century. “No question about it; there were El Niños that long ago,” says Daniel Schrag, professor of earth and planetary sciences. “The finding suggests that El Niños are much more stable than we ever thought.” Evidence of droughts and unusually wet weather, chemically etched into ancient reefs, show changes every three to seven years, a pattern that Schrag finds “remarkably similar” to those of El Niños from 1856 to 1976. After that, a sudden change occurred. Since 1976, the pattern looks completely different, with El Niño events appearing faster and stronger.