The El Niño of 2015-2016 was one of the strongest on record.
And now researchers have an idea about how it got so powerful.
In an April report, two researchers from the National Oceanic and Atmospheric Administration (NOAA) found that especially strong winds from summer 2014 didn’t just keep the 2014 El Niño from happening, they also gave the next year’s El Niño a headstart.
The wind in question, called “the boreal summer easterly wind burst,” stopped the growth of an El Niño back in 2014, but it also didn’t discharge any of the heat that had already built up. So by the time the 2015 El Niño started forming, it had quite a bit of extra heat to work with.
This past winter, El Niño led to seriously warm December temperatures on the East Coast while the south experienced flooding, and New Mexico, Texas, and parts of Oklahoma spent the weekend getting pummeled with a blizzard.
It’s forecast to wrap up this summer, and in April, the NOAA said it has initiated its La Niña watch after new predictions suggest it could be here as early as this fall.
La Niñas are marked by abnormally cooler sea-surface temperatures. Those cooler sea-surface temperatures also tend to reduce something called wind shear, a phenomenon that occurs when winds change their speed and direction over short distances. When winds can change their speed and direction quickly and easily, it makes hurricanes more likely because the area near the center of the storm can’t cool down.
If a La Niña does form, it won’t just increase the risks of a more intense Atlantic hurricane season. It could also lead to warmer and drier winters in the southern part of the US, while the Pacific Northwest, southern part of Alaska, and Midwest could feel the chill of cooler-than-average temperatures.