HCFC-22 emissions at global and regional scales between 1995 and 2010: Trends and variability

摘要

HCFC-22 (CHClF_2, chlorodifluoromethane) is an ozone-depleting substance, the consumption of which is controlled under the Montreal Protocol. Within a Bayesian inversion framework, we use measurements of HCFC-22 atmospheric concentrations to constrain estimates of HCFC-22 emissions, at the grid point 3.75°×2.5°and 8 day resolution, from January 1995 to December 2010. Starting from a new gridded bottom-up inventory which is then optimized, our method shows continuously rising global emissions, from 182±11 Gg in 1995 to the maximum of 410±9 Gg in 2009. This is mainly due to an increase of emissions in developing regions, particularly in Eastern Asia, and occurs despite the current phase-out in developed countries. The high temporal resolution of our inversion (8 day) allows to reveal some of the emission seasonality, the global posterior sources ranging from 25 Gg/month in November to 42 Gg/month in July, for example, in 2010. Key Points inversion of HCFC-22 emissions for the long period 1995 to 2010 reduction of the uncertainties associated with HCFC-22 emissions revelation of HCFC-22 emissions seasonality