ution ▁is ▁produced ▁in ▁meaning ful ▁quantities ▁after ▁the ▁Indust rial ▁Revolution ▁advance . ▁C ities ▁that ▁produce ▁a ▁lot ▁of ▁poll ution ▁will ▁start ▁to ▁produce ▁" de ad ▁t iles " ▁within ▁their ▁city ▁radius . ▁Such ▁t iles ▁produce ▁no ▁resources . ▁If ▁poll ution ▁is ▁left ▁un checked , ▁eventually ▁the ▁game ▁will ▁give ▁a ▁warning ▁that ▁global ▁dis aster s ▁will ▁occur . ▁Dis aster s ▁include ▁change ▁in ▁climate , ▁o zone ▁d eter ior ation , ▁and ▁global ▁war ming . ▁In ▁the ▁case ▁of ▁global ▁war ming , ▁the ▁game ▁inform s ▁the ▁player ▁that ▁" ice ▁caps ▁have ▁m elt ed " ▁and ▁sea ▁levels ▁have ▁ris en . ▁T iles ▁affected ▁are ▁turned ▁into ▁either ▁coast ▁or ▁shall ow ▁water , ▁and ▁cities ▁on ▁t iles ▁that ▁become ▁shall ow ▁water ▁or ▁coast ▁are ▁destroyed . ▁ ▁The ▁destruction ▁of ▁the ▁o zone ▁layer ▁causes ▁a ▁large ▁number ▁of ▁land ▁t iles ▁to ▁become ▁dead ▁t iles . ▁If ▁a ▁nation ▁is ▁appropri ately ▁techn olog ically ▁advanced , ▁then ▁that ▁nation ▁can ▁repair ▁dead ▁t iles , ▁but ▁only ▁at ▁a ▁significant ▁cost ▁of ▁industrial ▁production . ▁The ▁" G a ia ▁Controller " ▁wonder ▁removes ▁all ▁poll ution ▁in ▁the ▁game ▁but ▁can ▁be ▁built ▁only ▁in ▁the ▁Diam ond ▁Age . ▁ ▁Pol l ution ▁is ▁ex ac erb ated ▁by ▁several ▁city ▁facilities ▁such ▁as ▁fact ories ▁and ▁oil ▁ref iner ies . ▁On ▁the ▁f lip ▁side ,