English: Graph representing estimated cost involved in reaching atmospheric carbon dioxide concentration levels of 265 ppm, 350 ppm and 450 ppm targets. Graph is referenced from: Azar, C., Lindgren, K., Larson, E.D. and Möllersten, K.: (2005) “Carbon capture and storage from fossil fuels and biomass – Costs and potential role in stabilising the atmosphere”, Climatic Change, 74, 47-79