Images from the U.S./European Jason-3 satellite show sea surface height with respect to the seasonal cycle and the long-term trend. Blue/magenta colors indicate lower-than-normal sea levels, while yellow/red colors indicate higher-than-normal sea levels. The April 9, 2018 image (left panel) shows most of the ocean at neutral heights (green). A month later (right panel), a red patch is visible along the equator in the Central Pacific. The red area is a downwelling Kelvin wave, traveling eastward along the equator.