NASA’s new video showing how CO2 moves through the atmosphere is both eerie and mesmerizing.

The animation—based on a supercomputer model of five days in June 2006—illustrates the movement of atmospheric carbon dioxide from megacities and fires.

The simulation is designed to help scientists understand how the greenhouse gas behaves after it is emitted, what NASA calls the “other half” of the climate equation.

As countries meet in Paris later this month for U.N. climate talks on a global treaty to cut emissions, NASA scientists are working to identify how carbon already in the atmosphere acts and how carbon sequestration, in forests or wetlands, for example, may evolve as climate change progresses.