Estimated HCFC-142b emissions in China: 2000-2050.

1-Chloro-1,1-difluoroethane (HCFC-142b) was both ozone depleting substance under restriction of the Montreal Protocol on Substances that Deplete the Ozone Layer ( Montreal Protocol) and potent greenhouse gas with high GWP. Controlling its emissions in China will contribute to both mitigating climate change and protecting ozone. A national emission inventory of HCFC-142b for China during 2000-2012 was established and projected to 2050 based on the 2006 IPCC Guidelines for National Greenhouse Gas Inventories and the Montreal Protocol, showing that (i) in contrast to the downward trend revealed by existing researches, HCFC-142b emissions kept increasing from 0.1 kt/y in 2000 to the peak of 14.4 kt/y in 2012, making China a crucial contributor to global HCFC-142b emissions and (ii) for future emission projections, a continuous increase from 14.9 kt/y in 2013 to 97.2 kt/y in 2050 was anticipated under the business-as-usual (BAU) scenarios, while a reduction of about 90% of the projected BAU emissions would be obtained by fulfilling the Montreal Protocol, namely an accumulative mitigation of 1578 kt HCFC-142b from 2013 to 2050, equal to 103 kt ODP and 3504 Tg CO emissions. Emissions from each province in 2012 were also estimated to identify key emission areas. Among the 31 mainland provinces in China (Hong Kong, Macao, and Taiwan were not included), Jiangsu, Zhejiang, Shandong, and Guangdong had the highest emission rates in 2012 (2.06, 1.85, 1.52, and 1.04 kt/y, respectively); Zhejiang, Jiangsu, and Shanghai exhibit the strongest emission strength (0.83, 0.59, and 0.54 t/km, respectively), much higher than the average national level of 0.33 t/km. [ABSTRACT FROM AUTHOR]