(top) Annual surface temperatures around the world compared to average during La Niña episodes between 1950-2020. White dots show where patterns are statistically significant at the 95 percent confidence level. Most of the cooling during La Niña is in the tropics (blue colors), and much of it is over the ocean. Elsewhere, warm and cool departures mostly cancel each other out. (bottom) Change in average annual surface temperature over the 20th century. The greatest amounts of warming (darkest reds) are in the Northern Hemisphere over land. NOAA Climate.gov image, adapted from original by Chuan-Yang Wang.