Por Patrick Mazza
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Is humanity’s “invisible hand” reappearing?
In 1998 a monster El Niño was roiling the Pacific, skewing weather patterns all over the planet. The world had just experienced a string of record hot months. Then Vice President Al Gore was preparing for a press conference on the climate turbulence. An aide called Sierra Magazine Editor Paul Rauber to ask if he had any leads on the connection between intensifying El Niños and climate change.
“We have something in our latest issue,” Rauber replied.
“It’s on the top of my pile,” the aide chimed back.
The article was “The Invisible Hand,” subtitled, “As human activity warms the earth, El Niño grows more violent. Are we doing this to ourselves?” I was the author. In 1997, seeing a second super El Niño coming on after only 14 years, I dug into the question. I had been bringing climate change into my writing for nearly a decade, but this was my first deep dive into climate science.
I interviewed many climate scientists, including some of the absolute stars. Charles Keeling, who in 1958 led creation of the Mauna Loa monitoring station that is still the world’s leading CO2 measurement site (which the Trump Administration wants to shut down, for obvious reasons). Wallace Broecker, who identified the global interconnection of ocean currents and their capacity to cause abrupt climate change. In our interview, Broecker repeated the line he must have included in some version in every interview. “The Earth’s climate is like an angry beast, and we’re poking it with sticks.” Kevin Trenberth, chief scientist at the National Center for Atmospheric Research (another institution being dismembered under Trump). Trenberth had found the repeat of two super El Niños so close together probable to happen only once every 2000 years.
While the question of whether increasing global heating was driving El Niños was unsettled, the scientists repeatedly called out a key issue. What happens when normal climate variability such as El Niño piles on top of global heating? How will it impact the chaos an El Niño normally causes – droughts, wildfires, drenching storms, coral bleaching, agricultural collapse? It looks like we’re going to get some fresh answers to the question.
The monster El Niño now brewing in the Pacific seems on course to be the most intense on record, and by a long shot. Hotter by far than recent super El Niños in 1982-83, 1997-98 and 2015-16. Zeke Hausfather, a climate scientist with Berkeley Earth, puts it in context. His comments are all the more striking because he has a reputation for being reserved in his conclusions, as he confirms in the first line of a recent post at his Climate Brink site.
“I’m generally pretty measured in how I discuss climate data. There has been only one time in recent years when I was truly shocked: when global temperatures came in for September 2023 at a full 0.5C warmer than any prior September on record. Once until today, that is. With the July runs now in from 667 ensemble members across 14 different seasonal forecast models, it looks like this year’s El Niño is not only very likely to be the strongest event since reliable records began – it may end up the strongest by a truly mind-blowing margin.
“The multi-model median for the event’s peak . . . currently stands at 3.6C, roughly 0.8C hotter than the prior record of 2.75C set in 2015-16. For context, the gap between the strongest and the fifth strongest El Niño of the past 150 years is only about 0.5C. The models are forecasting something outside the envelope of anything we have ever observed.”
This graphic depicts just how far the current El Niño exceeds past El Niños,, including super El Ninos of the past five decades. Used with permission from Zeke Hausfather.
Hausfather reports other stunning facts. Ocean temperatures in the mid-Pacific are rising the fastest on record, and out of a cool La Niña condition. As of mid-July they were hotter than any time in a 45-year record of satellite measurements. “No El Niño has run this hot by July,” he says. 2026 was already on track to rank as one of the hottest years on record. These conditions have ramped up the probability 2026 will beat out 2024 as the hottest year from 13% at the beginning of July to 28% by mid-month. Because of El Niño, 2027 will almost certainly take the record with projections ranging around 1.7C, yet another year exceeding the Paris Climate Accords target of 1.5C maximum heating.
The planet is already in its 11th year of record or near record global temperatures. This has supercharged the atmosphere with water vapor that feeds inundations and flooding. Every degree Celsius translates into 7% more moisture in the atmosphere. This El Niño explodes on a world already roiled by global heating. It can only intensify the situation.
Is climate heating intensifying El Niño?
In order to parse out the El Niño-climate change connection, it is crucial to understand exactly what an El Niño is. Oceans absorb most solar heat accumulated by the planet. The Pacific is the largest ocean, covering nearly half the Earth’s surface. Its greatest solar collector is the tropical western Pacific. An El Niño is its heat discharge mechanism. It is the world’s largest interannual climate variability, and overall the biggest regular event on the planet other than the change of the 4 seasons. By a complex series of interactions, increasing heat weakens trade winds holding the warm pool to the west. It then migrates east in the classic tongue pattern seen in depictions of a full-blown El Niño. It gained its name, Spanish for “The Child,” because it has tended to have its greatest effects around Christmas. Fisherman in Peru felt it because the warm surface stops an upwelling of cool water that feeds fish populations, collapsing catches.
As the warm tongue reaches across the Pacific, its effects radiate throughout the world’s ocean and atmosphere system. It twists global wind currents such as the jet stream in ways that bring more rains to some regions while drying out others. El Niño is like a cue ball smashing into a rack and sending balls all over the table. The word used to describe this is teleconnections. Typical impacts are monsoon failure in India, drought and fires in Australia, Indonesia and the Amazon, and flooding along South America’s Pacific coast and in East Africa. The record heat currently driving a devastating fire season in France and Spain is in line with past super El Niños, as are heat domes in North America.
So in a heating world, shouldn’t the planet’s greatest collector of solar heat be discharging it more often and with greater intensity in the form of El Niños? That is the logic I pursued in my 1998 piece. But the climate system is incredibly complex, and temperature records only go back a limited time. Scientists are a cautious lot. They are more inclined to project that increasing heat will affect El Niños in the future, because of the basic logic. But they are still going back and forth on current impacts. So science is only slowly moving to the conclusion that El Niños are being made more frequent and powerful by global heating.
“It’s highly contested, because it’s such an important question to get right,” Brown University climate scientist Kim Cobb told the New York Times in a recent article, “Is Climate Change Supercharging El Niño? A Debate Rages.”
“Of 16 scientists who spoke with The Times, eight said they see compelling evidence that climate change is likely increasing the intensity of El Niño events. Among them is Michael McPhaden, a senior scientist at NOAA, who cautioned that the science is ‘very uncertain,’ but said the development of another strong El Niño this year would be ‘pretty remarkable.’ If the current El Niño reaches the proportions that many forecast, it would mean three of the six strongest events since 1950 have come in the last 11 years.”
Again, those are the 11 hottest years ever recorded on the planet.
One of the most definitive statements on the El Niño-climate change connection has been made by Wenju Cai, a climate scientist at Ocean University of China. Using advanced computer modeling to build a record of past El Niños, Cai and his team drew several critical conclusions. They compared the period from 1901-60 to 1960-2020. Three-quarters of model runs found events in the later period around 10% stronger on average. They compared the runs to a world in which greenhouse gases were at levels before the industrial revolution. The odds that these increases would have happened in such a world are 2.5-10%.
“It’s almost impossible for this to happen without climate change,” Cai told the New York Times.
McPhaden, a participant in the study, and chief scientist at NOAA Pacific Marine Environmental Laboratory in Seattle, a center of El Niño research, wrote,” One manifestation of this amplified cycle is that strong El Niño and La Niña events are becoming stronger and more frequent, just as we’ve observed in the more recent historical record. The big events pack the most punch, so even though 10% doesn’t sound like much, it juices up the strongest and most societally relevant year-to-year climate fluctuation on the planet . . . this amplified cycle translates into more extreme and frequent ENSO-linked droughts, floods, heat waves, wildfires and severe storms . . . “
When will we wake up?
What are broader implications of all this? It is beyond doubt that the heat release mechanism of El Niño will ramp up already devastating climate extremes breaking out all over the planet. If El Niños and their companion La Niñas are themselves amped up by global heating, it creates a feedback loop that makes those extremes all the more destructive.
Yet, as climate disruption reaches new levels, much of the world seems to be turning away from climate action. In the U.S., Trump is tearing apart climate science institutions and undermining clean energy growth, while Republicans continue to sing in the denier choir. Meanwhile, Democrats are climate hushing in the name of affordability, ironic in the face of how global heating is driving up grocery bills, home insurance and a plethora of other costs. In Europe, which has been a climate leader, nations under economic pressure are stepping back from net zero commitments. Global climate pollution continues to rise, though in one bright spot, China’s emissions appear to have peaked.
At one level, this introduces a sense of global cognitive dissonance. The intensification of climate impacts across the world should lead to a crisis response. We should be recognizing this is a global emergency. Instead it’s going the opposite direction. But there’s a schizoid logic in all this, a classic double bind. There is widespread knowledge that we face a critical situation. But we cannot collectively come to terms with what this means, the absolutely massive transformation of economic and energy systems that will be required. So we retreat into denial, soft or hard, that lets us go on with our day to day routines.
The question is what will wake us up? What will cause us to finally confront the necessity, when people push our political leaders to act while making the changes in our own lives that we must? We can hope what will take place in coming months will be so alarming it will stir the necessary response. But I’ve been at this long enough to have seen many events I thought would do this. Katrina’s destruction of New Orleans. Superstorm Sandy’s ravaging of New York City. So much as I hate to say it, I’m not optimistic. But we who are aware need to use this opening anyway. We need to call out the emergency situation facing our world, and especially media that do not make the connection between disasters and climate.
In any event, we are already in the age of climate extremes. They will only intensify from here on until we zero out climate pollution. So while we move toward zero, we also need to place a top priority on climate adaptation at every level, from local and state/provincial to national and international. We need to prepare our communities for the storms, floods, heat, drought and fires to come. Meanwhile, we need to continue to do all we can to reduce climate pollution, and bust business-as-usual assumptions that say we can stay on anything like the current course. If we continue, adaptation will become ever more difficult and eventually impossible. In the process of adapting, we must focus dual opportunities to adapt and reduce. For example, wetlands can buffer against floods and sea level rise while absorbing carbon. Sustainable agricultural practices can reduce farm pollution while absorbing carbon in soils. Better insulated buildings can protect against temperature extremes while cutting energy use.
Dealing with climate also offers chances to build a more just society. Climate disruption stresses all the fault lines in society such as widespread food insecurity. The immediate impact of this El Niño will worsen this as crops fail and prices increase. Over coming decades, food insecurity is likely to have the broadest climate impact on human populations. Too many people lack enough food already. We should address this anyway with comprehensive efforts to make sure people get enough, but a heating climate will drive us in this direction. It will take a strong society to cope with what’s coming.
It has been my hope that the multiple crises barreling down on the human race will make us a wiser species chastened by the consequences of our collective hubris. I have to say when I read news of what’s going on around the planet, I often feel a clenching in my gut. It sickens me we have gone so far while letting powerful interests throw away our collective future. At some point, we have to wake up. Let us do all we can to make this “mind-blowing” El Niño that point. May “The Child” cause us to think about our own, and the world we are leaving them.
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