By Evan Bush
Sea turtles are nesting in California, where they’d never been seen before. Hurricane Nolo in the Pacific is expected to dump 2 feet of rain on parts of Hawaii’s Big Island this weekend. And for the first time in at least 75 years, there hasn’t been a single hurricane in the Atlantic this season. All of these phenomena are likely effects of a record-setting El Niño.
Phil Klotzbach, a Colorado State University scientist, said this hurricane season has played out like a textbook example of what El Niño can do.
“If I were teaching a class and I wanted to talk about El Niño and what it looks like, I’d be like, “This is perfect. This is what I would use as my example,’” he said.
El Niño is a natural climate pattern characterized by a rise in sea surface temperatures in the eastern Pacific Ocean, which happens when winds near the equator weaken and the upwelling of cold water to the surface stalls.
Past El Niño events have spiked temperatures on land and driven powerful marine heat waves off the West Coast that caused die-offs and lured tropical fish to the north. The pattern is also associated with mild Atlantic hurricane seasons and more intense and frequent cyclones in the Pacific.
El Niño’s effects are most pronounced in winter, but the pattern is already more extreme for this time of year than any other on record.
“It’s definitely the strongest El Niño in recent memory,” said Allison Wing, an associate professor at Florida State University who studies tropical meteorology. “By winter, it could be the strongest El Niño in over 100 years.”
California Gov. Gavin Newsom proclaimed a state of emergency this week in response to El Niño’s threat in order to mobilize resources ahead of possible storms. He warned of debris flows, coastal flooding and heavy precipitation. El Niño is expected to erode California beaches with large waves.
The Southeast, meanwhile, can expect intense rain and the Pacific Northwest is likely in for less snow and high temperatures.
But so far, Hawaii has suffered the most extreme consequences. Hurricane Nolo will be the state’s third brush with a hurricane in less than two months, after Hurricanes Lala and Lowell.
Hurricane Nolo heads for Hawaii
The National Hurricane Center expects Nolo, currently a Category 1 storm, to strengthen into a major hurricane over the weekend and cause catastrophic flooding and life-threatening mudslides in Hawaii. Forecasters said parts of the Big Island could see rainfall totals of 10 to 15 inches, with total rainfall up to 25 inches in a few locations.
“It isn’t likely to actually make landfall in Hawaii, but is close enough to have rainfall impacts and wind impacts, potential flooding, mudslides, and of course, damaging surf and sort of unsafe sea conditions,” Wing said.
As of Friday morning, two other hurricanes were also churning in Pacific waters: Hurricane Odalys, a Category 4 storm, and Hurricane Polo, a Category 5 storm pointing toward Baja California in Mexico.
“We’ve had this kind of continuous train of hurricanes marching across the Pacific,” Wing said. “It’s been kind of relentless.”
Hurricane Polo is expected to strike Baja California early next week. NHC forecasters said the storm gained more than 100 mph in wind speed in a 24-hour period.
“We just saw one of the fastest rapid intensification events on record,” Klotzbach said, adding that based on its pressure measurement, Polo was the “second-strongest Eastern North Pacific hurricane on record.”
The Pacific is ‘as warm as it’s ever been’
El Niño events take place every two to seven years, and scientists typically measure their strength based on sea surface temperatures in the tropical Pacific Ocean, where the pattern is most pronounced.
Those temperatures are more than 5.2 degrees Fahrenheit higher than average, according to the University of Maine’s Climate Reanalyzer.
National Oceanic and Atmospheric Administration researchers use a three-month temperature average to measure El Niño (which subtracts the background warming of additional climate change). The index hit its second-highest mark since measurements began in 1950 for the months from June through August.
“When you look at the total temperature in the tropical Pacific at this moment in time, it’s as warm as it’s ever been,” said Ben Kirtman, the dean of the University of Miami’s Rosenstiel School of Marine, Atmospheric and Earth Science.
Those warm waters have supercharged hurricane season in the Pacific, but in the Atlantic, just six tropical storms have formed this year.
“We’ve never gone this late without a first hurricane,” Klotzbach said.
El Niño is associated with strong vertical wind shear in the Atlantic — when winds aloft are changing in strength and direction.
“When the winds are really strong high up in the atmosphere, it just basically tears apart the hurricane,” Klotzbach said.
Whale sharks, sea snakes and turtles nesting
Warm Pacific waters have also brought some unusual marine animals to the California coast, according to Cassandra Davis, who coordinates volunteers and community scientists at the Aquarium of the Pacific in Long Beach, California.
“We have seen photos and videos of everything from a whale shark to a sea snake to some unusual rays and other species,” Davis said.
Two nests of olive ridley turtles were discovered in Orange County. Previously, the farthest north the species had been known to nest is near Cabo San Lucas, Mexico, Davis said.
“This is the first time that they have been observed coming onshore in California or on the West Coast of the United States and actually laying eggs,” she said. “We are entering uncharted territories.”
Concerned about beach erosion and flooding, biologists moved about 200 sea turtle eggs to the aquarium to hatch, hoping to later return young turtles to the beach.
The extra heat in California’s coastal waters has taken a toll on some species, however.
“We are already starting to see a die-off of the kelp forest,” Davis said. “Our local kelp forests rely on cold temperatures, and that is affecting all of the species that we normally have off our coastline.”
Deadly heat
Some scientists think El Niño’s most pernicious effect will be its heat, and that 2026 could turn out to be the hottest year in modern history.
Researchers at the University of Chicago’s Climate Impacts Lab expect El Niño to raise global average temperatures more than 2 degrees Fahrenheit on top of the effects of global warming. The influence of El Niño alone could cause 451,000 excess heat deaths, they estimated in a recent paper that has not been peer reviewed.
“The number is so large, it’s numbing,” said Michael Greenstone, a University of Chicago professor who co-directs the lab.
Greenstone said his team released the analysis before completing peer review because the number of expected deaths was so stark that they wanted to give governments time to prepare.
Around the world, leaders should plan for cooling centers, prepare to provide medical care and improve access to water and electricity, he said.
“Places that are hot and poor are the most exposed,” Greenstone said. “It’s going to happen. We know where it’s going to happen. And we just feel like there is an urgent opportunity to save lives.”