This entry was published on the World Bank Voices blog in November 2015 as What El Niño teaches us about climate resilience.

It was recorded by the Spanish conquistadors, and triggered famines that have been linked to China’s 1901 Boxer Rebellion and even the French revolution.

Named by Peruvian fishermen because of its tendency to appear around Christmastime, El Niño is the planet’s most large-scale and recurring mode of climate variability. Every 2-7 years, a slackening of trade winds that push sun-warmed water across the Pacific contributes to a rise in water temperature across large parts of the ocean. As the heat rises, a global pattern of weather changes ensues, triggering heat waves in many tropical regions and extreme drought or rainfall in others.