These maps from NASA show ocean currents around the world.
The world's oceans are in constant motion, and this series of maps published by the NASA/Goddard Space Flight Center Scientific Visualization Studio helps provide us with a nice illustration of this movement. The maps, which were created at various times in past years, show the many warm and cold ocean currents responsible for transporting water across long distances throughout the world's oceans.
In addition to the ocean currents, you can also see swirly features, known as ocean eddies, on the maps. An ocean eddy is formed when currents sometimes pinch off into sections, creating the circular current. Sometimes significant eddies are given names, according to NOAA.
Below we have selected a few of the maps from NASA's collection, accompanied by a brief explanation of what you are seeing.
In addition to a large-scale view of ocean circulations and eddies across the world, you can also see water temperatures in this image. The orange and red shadings in the middle of the map correspond to the warmer waters in tropics. Cooler waters depicted in green and blue are located north and south of this as you head towards the poles.
Via Bonnie Bracey Sutton, Suvi Salo, Mark E. Deschaine, PhD, Jocelyn Stoller