El Niño has officially begun and is predicted to intensify into a very strong or “super” El Niño, with major changes in global weather patterns and even hotter weather, according to a new report released Thursday morning by the National Oceanic and Atmospheric Administration.
El Niño is a periodic weather pattern that occurs in the tropical Pacific Ocean, where winds change direction and generate extreme hot water in the central and eastern Pacific Ocean. These changes in wind and ocean temperatures have ripple effects on weather patterns around the world.
NOAA’s Climate Prediction Center says there is a 63% chance that this El Niño will be a “very strong” event (commonly known as a Super El Niño) and “the largest El Niño event in historical record since 1950.” In a sign that the center’s forecasts are reliable, it says there is a 100% chance that El Niño will continue into the fall, and a very high probability that it will continue into the winter.
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To be considered a Super El Niño, water temperatures in the tropical Pacific Ocean must be at least 2 degrees warmer than average. Some highly reliable computer models suggest that standards are significantly exceeded.
Over the past few months, changing winds have pushed large amounts of unusually hot water from the western Pacific Ocean to the eastern tropical Pacific Ocean. This unusually hot water has traveled about 600 to 1,000 feet below the ocean’s surface and is beginning to rise thousands of miles east to sea levels near South America. A similar phenomenon occurred during past severe El Niño events.
Super El Niño events are relatively rare, with recent occurrences occurring in 2015-16, 1997-1998, and 1982-83.
Because El Niño involves the transfer of large amounts of heat energy from the ocean to the atmosphere, this phenomenon also affects the global climate. In addition to human-induced warming trends from fossil fuel pollution, the Earth’s average surface temperature is rising, virtually guaranteeing that 2027 will surpass 2024 and set a new record for the warmest year on Earth.
Depending on your location, El Niño increases the odds of favoring certain weather and extremes, such as heat waves, floods, and droughts. In the United States, the effects are most pronounced during the winter.
Hurricanes: El Niño can intensify the hurricane season in the central and eastern Pacific, but tends to limit the number of hurricanes in the Atlantic. As El Niño events such as this one strengthen, the likelihood of such effects occurring tends to increase.
Depending on where individual storms track, hurricane season could pose problems for the southwestern United States and Hawaii.
Winter in the United States: Warmer-than-average conditions are typically seen across the northern United States, western Canada, and Alaska, but periods of colder weather may not be eliminated. The southern tier of the United States is often wetter and cooler because a more active jet stream induces more storms in the region.
• Atmospheric river events may occur more frequently in California as moisture-laden jet streams hit the coast, but it is difficult to predict which parts of the state will bear the brunt.
Floods, heat, and drought: Some regions, such as Australia and Indonesia, are prone to droughts and heatwaves during El Niño events, which can lead to wildfires and water supply concerns.
• In the summer, we are already seeing signs of a decline in monsoon rains in India and Southeast Asia. Reduced precipitation in these regions can exacerbate summer heat extremes.
• Droughts are also common in the Caribbean during El Niño events. Warm, dry winters are typical in some regions of South and East Asia. In southeastern Africa, drought conditions could become more severe during the austral summer, which runs from December to February. Meanwhile, areas near the Horn of Africa may experience heavy rains from October to January.
• In addition, parts of southeastern South America tend to experience heavy rainfall during El Niño, and southeastern Brazil experiences warmer-than-normal temperatures. The region of northern South America, which extends into parts of Central America, tends to be drier than normal from July to December. Northwestern South America, including Peru, is prone to heavy rains due to El Niño from January to May due to its proximity to abnormally hot seawater.
Oceans: El Niño events can cause widespread marine heatwaves and coral bleaching, making corals more sensitive to rising ocean temperatures. Marine heatwaves themselves can also influence local weather patterns.
Economic impact: Research shows that strong El Niño events can reduce economic growth in countries through disaster losses, food supply disruptions, and other impacts.
But that’s not all. Individual El Niños, even very strong El Niños, do not follow exactly the predicted impacts, which can lead to surprises.
There is even more uncertainty regarding the effects of this Super El Niño. That’s because the phenomenon is occurring at a time when the world is already much hotter than average due to global warming caused by fossil fuel pollution. Therefore, there are some questions about how it will increase the magnitude of El Niño-related extreme weather events.
In other words, when the background climate was as warm as it is today, there has never been an El Niño or even a Super El Niño.
CNN meteorologist Chris Dolce contributed to this article.
