Title: Atmospheric histories and growth trends of C4F10, C5F12, C6F14, C7F16 and C8F18

Abstract: New atmospheric observations are presented for the high molecular weight perfluorocarbons (PFCs): C4F10, C5F12, C6F14, C7F16 and C8F18, based on 36 Northern Hemisphere and 46 Southern Hemisphere archived air samples, with fill dates from 1973 to 2011. The 2011 atmospheric mole fractions contribute 0.35mW/m2 to the Earth's radiative budget, which is 6% of the total PFC radiative forcing (including CF4, C2F6, C3F8 and c-C4F8). Annual growth trends based on the observations peak in the 1990s, suggesting that the high molecular weight PFCs usage increased as CFCs were phased out under regulation of the Montreal Protocol.

Speaker's website: http://www.mit.edu/~divy/

Host: Daniela Domeisen
Faculty host: Ron Prinn