KCS

Man-made chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) have been widely used in many industrial applications such as degreasing solvents in semiconductor/electronics, foam-blowing agents, aerosol propellants and refrigerants. However, because of their involvement in stratospheric ozone depletion, the production and consumption of these compounds have been regulated by the Montreal Protocol on Substances that Deplete the Ozone Layer and its Amendments. High-frequency in situ measurements of a wide range of man-made halogenated compounds have been made at Gosan (Jeju Island, Korea) since November 2007 as part of AGAGE global network. These halogenated compounds are measured in 2 L ambient air samples every two hours using automated custom?built cryogenic pre-concentration system coupled with gas chromatograph and mass selective detector (GC-MSD) with relative measurement precisions typically less than 1%. Using an interspecies correlation method with annual and average of HCFC-22 emissions, which is calculated with an inverse method based on a Lagrangian particle dispersion model (FLEXPART), we could estimate the emission rates of anthropogenic halocarbons. Our results, a unique “top-down” approach, suggest that overall China is the dominant emitter of HCs in East Asia with global fractions reaching 20% of total global emissions for many individual species, while significant emissions are also found in South Korea, Japan and Taiwan for some specific compounds such as HFC-134a, SF6, CH3CCl3, and HFC-365mfc. Our results also confirm the signs of successful phase out of primary ozone-depleting species along with substantial emissions of replacement HCFCs. Further implication of these high frequency high quality data will be discussed at the meeting.