The Pacific Ocean behaves like a conductor setting the tempo for outages in the American power grid. When the ocean shifts into its cold phase, known as La Niña, lights start going out more often across the US. Researchers traced this connection over 24 years and confirmed that the ocean really does drive the weather, and the weather batters wires and transformers.
The conductor does not just wave a baton; it sends notes through three channels. In the western US, La Niña intensifies cold snaps and extreme precipitation; in the southeast, heat waves; and in the mid-eastern states, extreme precipitation again. Each channel strikes a different part of the power system: snow and ice topple trees onto lines, heat pushes air conditioners to their limit, and downpours flood substations.
The connection turned out to be not just noticeable but predictable. Outages do not rise simultaneously with La Niña; they lag by several months. That is, the ocean gives the command first, and only then does the power system begin to stumble. In spring after a La Niña peak, outage rates hit their maximum. In six of ten US climate regions, the correlation between La Niña intensity and outage counts reaches -0.68, and in some regions it goes as high as -0.82. This means that the stronger the cold phase, the more outages occur.
By the end of the century, the conductor may shift to a louder score. If greenhouse gas emissions remain high, by 2081–2100 spring heat-related outages in the eastern US could grow nearly 26-fold compared with 2000–2023. Even under a moderate scenario, the increase would be 13-fold. A power system built for the past climate would find itself in the climate of the future.
Previously, no one had linked El Niño to power system failures. Now it is clear that forecasting the ocean's phase months ahead could serve as an early warning for energy operators. If meteorologists predict a strong La Niña, utilities can inspect equipment in advance, stockpile repair crews, and alert customers. The ocean continues to conduct, but now the orchestra has a score.
In spring 2018, a storm in California brought heavy snowfall and cold, leaving 10,898 customers without power and causing a loss of 38 MW of demand. And in March 2023, a series of tornadoes with extreme precipitation blacked out about one million customers across more than ten states.