Estimate of Hydrofluorocarbon Emissions for 2012-16 in the Yangtze River Delta, China

Hydrofluorocarbons (HFCs) have been widely used in China as substitutes for ozone-depleting substances, the production and use of which are being phased out under the Montreal Protocol. China is a major consumer of HFCs around the world, with its HFC emissions in CO2-equivalent contributing to about 18% of the global emissions for the period 2012-16. Three methods are widely used to estimate the emissions of HFCs-namely, the bottom-up method, top-down method and tracer ratio method. In this study, the tracer ratio method was adopted to estimate HFC emissions in the Yangtze River Delta (YRD), using CO as a tracer. The YRD region might make a significant contribution to Chinese totals owing to its rapid economic growth. Weekly flask measurements for ten HFCs (HFC-23, HFC-32, HFC-125, HFC-134a, HFC-143a, HFC-152a, HFC-227ea, HFC-236fa, HFC-245fa and HFC-365mfc) were conducted at Lin'an Regional Background Station in the YRD over the period 2012-16, and the HFC emissions were 2.4 +/- 1.4 Gg yr(-1) for HFC-23, 2.8 +/- 1.2 Gg yr(-1) for HFC-32, 2.2 +/- 1.2 Gg yr(-1) for HFC-125, 4.8 +/- 4.8 Gg yr(-1) for HFC-134a, 0.9 +/- 0.6 Gg yr(-1) for HFC-152a, 0.3 +/- 0.3 Gg yr(-1) for HFC-227ea and 0.3 +/- 0.2 Gg yr(-1) for HFC-245fa. The YRD total HFC emissions reached 53 Gg CO2-e yr(-1), contributing 34% of the national total. The per capita HFC CO2-equivalent emissions rate was 240 kg yr(-1), while the values of per unit area emissions and per million GDP emissions reached 150 Mg km(-2) yr(-1) and 3500 kg yr(-1) (million CNY GDP)(-1), which were much higher than national or global levels.