In order to be considered an El Niño, temperatures in that zone need to be 0.5 C above the average.
And then five paragraphs later they even explain it more.
El Niño and La Niña are part of a larger, natural cyclical cycle called the El Niño Southern Oscillation (ENSO), which occurs in a specific part of the Pacific Ocean.
It’s the fifth paragraph…
And then five paragraphs later they even explain it more.