Ben Kirtman says the current super El Niño is pushing weather forecasting into uncharted territory. The dean of the University of Miami’s Rosenstiel School of Marine, Atmospheric, and Earth Science says the event could rival past records while the planet is much warmer than when earlier extreme El Niño events unfolded.
Michael McPhaden, a senior scientist recently retired from the National Oceanic and Atmospheric Administration, said three El Niño events over the past 50 years were considered extreme: 1982-83, 1997-98 and 2015-16. He said the current event will rival those previous record El Niños, if not exceed them in magnitude.
Daniel Swain on warmer climate
Daniel Swain, a climate scientist with the University of California Agriculture and Natural Resources and founder of WeatherWest.com, said scientists have never experienced an extreme El Niño in a climate as warm as today's climate. He put it plainly: “We've never experienced an extreme El Nino in a climate as warm as the climate is today”.
Swain also offered a simple way to think about the overlap. “If El Nino gets us to the 8th or 9th floor, that plus global warming is going to get us to the 10th or 11th floor.” For people in the United States, that means the winter forecast cannot rely on history alone when the base climate has shifted upward.
NOAA July records and warmer oceans
NOAA reported that July in the contiguous United States was record warm, and that the global average temperature was tied for the second warmest July on record. Michael McPhaden said every year in the decade since 2016 has been among the globe's warmest 10 years on record, while sea surface temperatures are warmer than normal and in some cases have been record-warm for this time of year.
That combination matters for the Pacific Ocean and the weather patterns tied to El Niño in the United States, Southeast, California and Indonesia. Kirtman said this is “an El Nino superimposed on top of a pretty big climate change signal.”
October and January peak window
The unresolved question for this winter is how El Niño and climate change will interact to influence weather in the United States and around the globe. Kirtman said scientists know El Niño and climate change separately, but do not have a clear understanding of how the warming climate will influence El Niño's relationships with the atmosphere and weather. He added, “There are some profound unanswered questions”.
El Niño is not forecast to reach peak intensity until sometime between October and January, so the sharpest effects may still be ahead. “We're already in 'uncharted territory' with how fast the current El Niño “has taken off,” and in terms of how much warmer temperatures are forecast to be by the end of the year, he said. "We're setting record after record already."”
Kirtman said, “The prediction of El Nino has become so routine, it's easy to sort of forget that we need to do more research.” El Niño puts Earth in 'uncharted territory. Here's what could happen sits alongside other recent coverage, but the climate signal now developing is its own test of what seasonal forecasting can handle. The practical takeaway for readers is that the usual El Niño playbook may not fit cleanly this time, because the event is arriving on top of a much hotter baseline.
