⚡ The other half of the ocean’s energy

This globe maps the kinetic energy carried by ocean eddies: not the average current, but the swirls that form around it. Every mesoscale eddy detected by satellite altimetry between 1993 and 2023 contributes, and where that energy is high the surface bulges outward.

🔥 The western boundaries. The Gulf Stream, the Kuroshio, the Brazil-Malvinas confluence and above all the Agulhas, south of Africa, burn brightest. These currents are unstable: they meander, pinch off rings, and shed them into the open ocean. The Agulhas leaks rings into the Atlantic that survive for years and carry Indian Ocean water across an entire basin.

🌊 The Southern Ocean is a continuous ring of energy with no western boundary to lean on. The Antarctic Circumpolar Current has no continent to press against, so it becomes unstable along its whole length.

💨 The Somali Current and the Arabian Sea flare seasonally with the monsoon, one of the few places where the ocean reverses direction twice a year.

🕳 And the dark interiors. The centres of the subtropical gyres carry an order of magnitude less energy. Most of the ocean is quiet; the violent parts are narrow.

⚖️ Why this matters. Eddy energy in the ocean is comparable to, and in many regions exceeds, the energy of the mean flow. These swirls do much of the work of moving heat, carbon and nutrients around the planet, which is why ocean models that cannot resolve them get the climate wrong.

⬇️ Worth keeping in mind: this is the energy of eddies identified one by one in the atlas, averaged per detection, and includes every eddy regardless of how long it lived. It is not the same quantity as the mean kinetic energy globe we posted earlier, which was the energy of the average current.

The relief is a visual device to make the pattern readable, not real topography. Grey is land and areas without eddy detections.

Data: META 4.0 mesoscale eddy atlas (AVISO/CLS/CNES), DUACS altimetry