The ocean and atmosphere are constantly trading heat, and that exchange isn't random, it's structured by currents, wind patterns, and geography. This animation shows the 1979-2025 mean net heat flux at the ocean surface (ORAS5 reanalysis), in W/m². Red means the ocean is gaining heat from the atmosphere; blue means it's losing heat to it. Land is shown in flat gray.

Ocean and atmosphere trade heat constantly, and this animation shows just how much that exchange follows the sun. It's the monthly net heat flux at the ocean surface (ORAS5 reanalysis, 1979-2025), in W/m². Red means the ocean is gaining heat from the atmosphere; blue means it's giving heat back.