"Yellow Zones" is a term for a particular region. The Yellow Zones covered approximately 50 percent of Earth's surface by 2047. Most of these areas had suffered from social collapse due to Tiberium infestation, extreme weather changes caused by Tiberium, and decades of war. Despite the worsening conditions, Yellow Zones still held 80 percent of the world's population in 2047. Cities in the most afflicted areas in these zones were run by warlords and criminal organizations or had degenerated into anarchy. Many other areas were controlled by the Brotherhood of Nod, though some cities, particularly those situated in close proximity to the Blue Zones, acted as staging areas and frontline bases for GDI. As a result, conditions in the latter cities tended to be better than those in the "worst of