A staggeringly high-resolution animation has been produced showing what happened to the Pacific during the record-breaking El Niño of 1997-98, and the La Niñas that followed. The visualization is so complex, showing ocean temperatures to a depth of 300 meters (980 feet) along with atmospheric effects, that it required 30,000 hours of computer processing time on Australia's most powerful supercomputer to model the data.
El Niños were originally identified by the warm waters off the west coast of South America, but we now know they involve a set of regional climatic effects that can trigger natural disasters around the globe. The video below provides an introduction to the effects of these enormous systems on countries of the Pacific Rim. More importantly, the project will help extend the warning time meteorologists can provide before future events, helping many forms of planning, such as farmers working out which crops to plant.
The string of temperature records broken through 2015-2016 was the consequence of a major El Niño combined with the long-term effects of global warming. The 1997-1998 event represented the strongest deviation from underlying conditions since we have had good observation systems, but as the baseline was then lower, global temperatures never got quite as high.
The El Niño led to floods in California, droughts in many other parts of the world, fires that devastated Indonesia's rainforests and the world's first global coral bleaching event. Understanding what happened has been a priority for climate scientists in order to grasp what the future holds.
“The animation shows how shifting pools of warmer or cooler than average water 300m below the surface of the ocean can trigger these powerful events,” said Dr Alex Sen Gupta of Australia's Centre of Excellence for Climate System Science in a statement. “When these pools of water burst through to the surface and link up with the atmosphere they can set off a chain reaction that leads to El Niños or La Niñas.”