Emission estimates of HCFCs and HFCs in California from the 2010 CalNex study

摘要: [1] The CalNex 2010 (California Research at the Nexus of Air Quality and Climate Change) study was designed to evaluate chemical composition air masses over key source regions in California. During May June 2010, samples were collected on board a National Oceanic Atmospheric Administration (NOAA) WP-3D aircraft South Coast Basin California (SoCAB) Central Valley (CV). This paper analyzes six effective greenhouse gases—chlorodifluoromethane (HCFC-22), 1,1-dichloro-1-fluoroethane (HCFC-141b), 1-chloro-1,1-difluoroethane (HCFC-142b), 2-chloro-1,1,1,2-tetrafluoroethane (HCFC-124), 1,1,1,2-tetrafluoroethane (HFC-134a), 1,1-difluoroethane (HFC-152a)—providing most comprehensive characterization chlorofluorocarbon (CFC) replacement compound emissions Concentrations measured HCFCs HFCs are enhanced greatly throughout SoCAB CV, with highest levels observed SoCAB: 310 ± 92 pptv for HCFC-22, 30.7 ± 18.6 HCFC-141b, 22.9 ± 2.0 HCFC-142b, 4.86 ± 2.56 HCFC-124, 109 ± 46.4 HFC-134a, 91.2 ± 63.9 HFC-152a. Annual emission rates estimated all compounds using halocarbon carbon monoxide (CO) mixing ratios CO inventories. Emission 3.05 ± 0.70 Gg 0.27 ± 0.07 0.06 ± 0.01 0.11 ± 0.03 1.89 ± 0.43 1.94 ± 0.45 HFC-152b year calculated SoCAB. These extrapolated from region state population data. Results this provide baseline rate that will help future studies determine if HCFC HFC mitigation strategies successful.