November 7, 2023

With the current El Niño in full force, researchers are still puzzling over the 2020–2023 La Niña that upended current understanding of El Niño Southern Oscillation (ENSO) dynamics. The three consecutive years of La Niña conditions – a rare “triple-dip” phenomenon – had widespread impacts on the ocean and climate across the globe. While triple-dip La Niñas have happened before, this one was notable in that it did not conform to conventional theories on how these extended La Niñas develop, leaving scientists searching for clues to explain what caused it.