Domes are large half-spherical structures on the outskirts of larger cities.
They are apparently enclosed areas for people to live in, but only those people rich enough to afford it. Despite being closed off, some still contain pollution creating machinery; however, inhabitants do not need to wear rebreathers. ("Genesis", "Occupation-Resistance")
Elisabeth Shannon had connections which could have allowed her to live in one of the domes, but refused to do so as it would drain resources for future generations. Mira was part of a secessionist movement within a dome which was raided by the army. Phoenix Group amassed and prepared for their invasion of Terra Nova in a dome not far from Hope Plaza and Weaver mentioned he intended to buy his own dome from the profits he was going to make. ("Genesis", "Now You See Me", "Occupation-Resistance")