Aério is a prototype for urban surfaces and a soft machine conceived as a macro-breathing organ that explores forms of cohabitation of species through the ecology of breathing. The project links three main fields of inquiry: the public realm, socio-technical systems, and health. By mapping prototypical public spaces, the project aims to predict scenarios for dynamic absorption of CO2 in the public realm by interpolating data relative to material technology, human occupation, density, and surrounding air ecologies.