A severe El Niño climate cycle is combining with record-hot ocean waters and a marine heat wave to intensify heavy rains, coastal flooding, and extreme sea levels across the American Southwest and Pacific Coast, according to scientists.
Why is this El Niño event considered particularly extreme?
The natural warming cycle is sizzling Pacific Ocean waters and leaking moisture into the air to fuel passing storms, according to experts. Meteorologist Jeff Masters of Yale Climate Connections described the current iteration as a “super duper El Niño.” Former National Oceanic and Atmospheric Administration chief scientist Ryan Maue calculated that over 20 trillion gallons of water have fallen on the Four Corners states and Nevada in a two-week span.
Climate scientist Daniel Swain with the University of California Agriculture and Natural Resources noted that the precipitation levels in the Southwest interior exceed anything recorded previously. The phenomenon is also driving record-breaking flooding in regions such as Peru and Ecuador, according to Swain.
What role are ocean temperatures and Kelvin waves playing on the coast?
Significant coastal flooding in Southern California highlights a worst-case scenario for the winter season. Robbie Munroe, a meteorologist with the National Weather Service office in Oxnard, explained that waters have surged a foot to a foot and a half above normal levels due to warm temperatures and Kelvin waves. These waves slowly transport warm water thousands of miles from the western Pacific Ocean toward the eastern Pacific near Peru.
Patrick Barnard, Research Director of UC Santa Cruz’s Center for Coastal Climate Resilience, noted that ocean conditions have become “alarming” after observing more than five months of El Niño developments. Barnard noted that tide anomalies reached up to 18 inches above predictions in San Diego and Los Angeles, adding that sea level anomalies could hit two feet during the winter.
How are marine ecosystems and coastal wildlife reacting?
The warming waters and incoming storms threaten marine life ecosystems along the Central Coast, according to Ben Ruttenberg, Director of the Cal Poly Center for Coastal Marine Sciences. Rising tides cause habitat compression, forcing marine life closer to the shore. Morro Bay estuaries face increased freshwater input that alters water salinity and turbidity, which can reduce prey diversity for local southern sea otters that must consume a quarter of their body weight daily to stay warm.
At the same time, tropical species have migrated closer to the California coastline. The region has recorded sharks and manta rays near Malibu, alongside bluefin tuna and garibaldi fish in Morro Bay, according to Ruttenberg.
What preparations are experts recommending for residents?
Millions of Americans have been urged to stockpile emergency supplies and secure their homes as NOAA forecasts a strong El Niño carrying destructive storms, flooding, and landslides. Mike Bettes of The Weather Channel warned that prior strong El Niños signal an active season for atmospheric rivers in Southern California that could trigger disastrous flooding and landslides.
Power engineer Heather Eason advised residents to acquire emergency supplies, including power generators, phone power banks, LED lanterns, batteries, portable battery power stations, extension cords, propane for gas grills, and solar panels. Meanwhile, Michele L’Heureux, a physical scientist at NOAA, told ABC News that seasonal forecasts rely on probabilities and that weather impacts can vary by location.
Frequently Asked Questions
When is the El Niño event expected to peak?
Experts expect the current El Niño event to peak in December, though its impacts could continue for months afterward into the spring and summer.
What specific sea level records were broken recently in California?
Water levels reached 8.26 feet on one day and 8.19 feet the next, surpassing the previous record of 7.93 feet set on January 10, 2005, during an El Niño winter.
How does the eastern Pacific sea surface temperature index measure this event?
NOAA uses sea surface temperature indices in the eastern and east-central Pacific to measure El Niño strength, classifying any reading over 2 degrees Celsius above the norm as a super El Niño. The index reached 2.2 degrees Celsius, up from 0.5 in April.
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