It remains to be seen whether it will be a “very strong” or “super” El Niño, but a strong Pacific pattern is expected to emerge this summer.
The federal government’s latest projections give an 82% chance of an El Niño forming by July, according to a May 14 update from the National Oceanic and Atmospheric Administration’s Climate Prediction Center.
Zeke Hausfather, director of climate and energy at the Breakthrough Institute and a researcher at Berkeley Earth, said on May 8 that many predictive models indicate this event could be “one of the strongest El Niño events in recent history.” But he and other officials say it’s too early to know for sure how strong the phenomenon will be.
AccuWeather has raised the probability of a “super” El Niño to 30% by the end of the Atlantic hurricane season in November.
Either way, this summer will likely be remembered for the extreme weather caused by El Niño, said Paul Pastelok, chief long-range expert at AccuWeather.
The El Niño pattern is part of a natural cycle that unfolds over three to seven years in the Pacific Ocean, tends to increase global temperatures, and is considered one of the most influential climate patterns on Earth.
Here’s what we know about a possible “super” El Niño.
ocean water warming
Atmospheric signatures of El Niño include a weakening or reversal of trade winds, a reversal of Pacific pressure patterns, an eastward shift in precipitation and convection, and changes in the jet stream and global wind patterns, all of which collectively indicate the ocean-atmosphere system has entered the El Niño phase, NOAA said.
As sea surface temperatures in the eastern tropical Pacific Ocean increase by at least 0.5°C (0.9°F) above the long-term average, changes in atmospheric patterns, including changes in winds, surface pressure, and precipitation across the region, begin to accelerate.
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NOAA tracks sea surface temperatures using satellite instruments that measure the energy emitted by the ocean at different wavelengths. These satellite observations are combined through computer models with temperature data collected from ships and buoys, and information from sea ice charts.
Ocean temperatures around the world have been rising for decades. But from 2023 to 2024, global sea surface temperatures will experience an unusual and prolonged record rise, USA TODAY previously reported.
What is “Super” El Niño?
The word “super” is often used when sea surface temperatures in the tropical Pacific Ocean rise up to 3.6 degrees Fahrenheit above average for several months. However, NOAA has not officially defined a “super” El Niño category.
According to NOAA, this El Niño has an 82% chance of occurring between May and July and is expected to last until the end of 2026.
What are the characteristics of El Niño phenomenon?
El Niño is a natural climate pattern in which sea surface temperatures in the central and eastern tropical Pacific Ocean are warmer than average.
The entire natural climate cycle is officially known as El Niño (Southern Oscillation), and scientists refer to it as ENSO. This cycle moves back and forth between warm and cold ocean water in areas along the equator of the tropical Pacific Ocean. La Niña is characterized by lower than average seawater levels in the region.
The name means little boy or Christ child in Spanish. El Niño was originally recognized by fishermen off the coast of South America in the 1600s when unusually warm water appeared in the Pacific Ocean around Christmas.
Weather effects due to Super El Niño
El Niño causes widespread weather effects around the world, including parts of the United States. El Niño can affect the number of hurricanes that form in both the Atlantic and Pacific Oceans, but it has an even greater effect on winter weather in the United States.
If it happens by summer, “we would likely see a dangerous heat wave across parts of the West and South. Storms and flash flooding could pose the biggest problems from the Plains to the Ohio Valley,” Pastelok said. Drought and wildfire risk will also be major concerns in the Northwest. ”
Even if the strongest parts of El Niño don’t arrive until the end of the year, it could be strong enough to impact the hurricane season, which begins May 15 in the eastern Pacific and June 1 in the Atlantic hurricane basin.
El Niño typically suppresses Atlantic hurricanes by increasing wind shear, which tends to tear apart developing storms. In the Pacific Ocean, the opposite occurs as water temperatures increase and wind shear decreases.
“Simply put, El Niño increases hurricane activity in the central and eastern Pacific Basin and suppresses hurricane activity in the Atlantic Basin,” NOAA said in an online report.
Super El Niños do not occur frequently. Only four have occurred since 1950. The most recent one occurred between 2015 and 2016, according to the Weather Channel.
Doyle Rice writes for USA TODAY
