The remaining emissions in all other countries were disaggregated according to the Population Density Grid Future Estimates v3. For disaggregation of global emissions to different countries, for HFC-134a, HFC-32, and SF 6, emissions at country level including Japan were taken from the United Nations Framework Convention on Climate Change data set. A detailed gridded a priori emission data set was developed by spatially disaggregating recent reported global emissions and their trends. The inversion method used in this study is based on backward Lagrangian particle dispersion model calculations from the measurement stations using FLEXible PARTicle (FLEXPART) model, which establishes source-receptor relationships between emissions and atmospheric concentrations. For the inversions, we ignored this small difference. Intercomparison experiments between the calibration scales for CFC-11 measurement showed agreement within ☑%. For Hateruma and Ochiishi, the measurements are reported on the NIES-08 calibration scale, whereas for Ryori, the JMA calibration scale was used. At the Ryori Global Atmospheric Watch regional station (39.3°N, 142.3☎), halocarbons including CFC-11 have been measured by the Japan Meteorological Agency (JMA) using a gas chromatograph equipped with an electron capture detector. Halocarbons are quantified with gravimetrically prepared standard gases, which are analyzed in the same manner as the ambient air samples after every five air analyses. Ambient air is analyzed with a fully automated preconcentration/gas chromatography/mass spectrometry system. Hourly measurements of halocarbons have been performed at Hateruma (24.1°N, 123.8☎) and at Ochiishi (43.1°N, 145.3☎) as part of the National Institute for Environmental Studies halocarbon monitoring project. Halocarbons including CFCs, HCFCs, HFCs, PFCs, halons, and SF 6 have been measured at Hateruma and Ochiishi, and ozone-depleting substances including CFCs have been measured at Ryori. By combining the atmospheric measurements with an atmospheric transport model and an inverse method, we estimate halocarbon emissions from Japan. In this study, we present in situ measurements of atmospheric halocarbons at three Japanese stations (Hateruma Island, Cape Ochiishi, and Ryori). However, there is little information about the impact of the earthquake on halocarbon emissions. Destruction of building components containing halocarbons may be expected to release these substances into the atmosphere. On 11 March 2011, the Tohoku earthquake and tsunami brought extensive damage to northeastern Honshu Island. HFCs are powerful greenhouse gases and are therefore included in the Kyoto Protocol to the United Nations Framework Convention on Climate Change together with other greenhouse gases (e.g., sulfur hexafluoride (SF 6) and perfluorocarbons (PFCs)). Although CFCs reside in certain products (e.g., building insulation foam) and HCFC are still used, HFCs are currently used in developed countries as major substitute gases for the ozone-depleting substances and HFCs emissions are rapidly increasing. However, CFCs and HCFCs are regulated under the Montreal Protocol on the Substances that Deplete the Ozone Layer because of their contributions to stratospheric ozone depletion. Halocarbons such as chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), and hydrofluorocarbons (HFCs) have been widely used for a variety of applications such as refrigerants in refrigerators and air conditioners and as blowing agents in foam manufacture.
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