An iceberg stuck in shallow waters, pushed by meltwater from the Jakobshavn glacier


© Ian Berry / Magnum Photos

The Jakobshavn glacier in Greenland is an old, wise, white castle. Fractures advance along crumbling walls, then the towers collapse with deafening roars. The shattered ice fragments float and melt, releasing droplets of fresh water in the salty ocean water. Let's refresh our memories of science lessons. Water density varies according to temperature and salinity. Cold water is denser than hot water and salt water is denser than fresh water. In our minds, let's follow the droplets of cold, heavy salt water, moving in the deep, creating the largest current in our oceans, from the poles to the Equator. In an effect of equilibrium, on the surface, a parallel and contrary motion takes warmer, oxygenated water, full of nutrients, to the poles. An incredible dance of the oceans called thermohaline circulation allows millions of cubic metres of water to move, bringing life to the entire ocean.
The ice mass of Greenland is melting fast. The white ruined castle tells us that this vital motion is slowing down. The water flowing to the poles is getting warmer and less saline, thus less dense, and the tiny droplet we are following plunges down at a decreasing velocity. Water plays a key role in the climate system and in life on Earth. Ocean currents regulate marine ecosystems. They mitigate the climate of zones like Western Europe, making them habitable and allow rain clouds to form in zones like the Sahel in Africa, which would otherwise be deserts.
Let's imagine the ocean currents as incredible dancing ribbons, animated by the pulsing movements of the icy polar depths. This vital rhythm is also our rhythm. We have the chance to abandon some of our habits and be part of this dance too.

Lucia Zaccaria