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.

The fact that we are undergoing a major El Niño event should cause major concern and requires mobilization now. Already, eight provinces in the Philippines are in a state of emergency due to drought; rice farmers in Vietnam and Thailand have left fields unplanted due to weak rains; and 42,000 people have been displaced by floods in Somalia.

And this is before the event reaches its peak. Meteorologists see a 95% chance of the El Niño lasting into 2016, with its most extreme effects arriving between now and March. Coastal regions of Latin America are braced for major floods; India is dealing with a 14% deficit in the recent monsoon rains; and poor rainfalls could add to insecurity in several of Africa’s fragile states. Indeed, Berkeley Professor Soloman Hsiang has used historical data to demonstrate that the likelihood of new conflict outbreaks in tropical regions doubles from 3% to 6% in an El Niño year.

But despite its thousand-year history, the devastation associated with El Niño is not inevitable. Progress made by many other countries since the last major event, in 1997-98, shows that we can get a grip on its effect – and others caused by climate trends.

For the complete article, please see the World Bank Blog 'Voices'.