Nitryl chloride(ClNO2)is a product of nocturnal halogen activation of nitrogen oxides and has potential to impact atmospheric photochemistry.Here we report the first observation result of ClNO2in an Asian environment....Nitryl chloride(ClNO2)is a product of nocturnal halogen activation of nitrogen oxides and has potential to impact atmospheric photochemistry.Here we report the first observation result of ClNO2in an Asian environment.The measurements were made with a thermal decomposition chemical ionization mass spectrometer at a coastal site in southern China during late summer of 2012.A clear diurnal pattern of ClNO2was observed with nighttime 1-min average mixing ratio up to 1997 pptv,which is among the highest values ever reported in the world.The elevated ClNO2mixing ratios were observed in plumes from Hong Kong and the Pearl River Delta region compared to the lower levels in maritime air.Calculations suggest that the production of chlorine atom from photolysis of ClNO2in the early morning exceeds the production of hydroxyl radical via ozone photolysis by several factors.Therefore,ClNO2plays an important role in jump-starting the atmospheric photochemistry in polluted marine boundary layer of southern China.展开更多
基金supported by the Research Grants Council of Hong Kong(PolyU5015/12P)
文摘Nitryl chloride(ClNO2)is a product of nocturnal halogen activation of nitrogen oxides and has potential to impact atmospheric photochemistry.Here we report the first observation result of ClNO2in an Asian environment.The measurements were made with a thermal decomposition chemical ionization mass spectrometer at a coastal site in southern China during late summer of 2012.A clear diurnal pattern of ClNO2was observed with nighttime 1-min average mixing ratio up to 1997 pptv,which is among the highest values ever reported in the world.The elevated ClNO2mixing ratios were observed in plumes from Hong Kong and the Pearl River Delta region compared to the lower levels in maritime air.Calculations suggest that the production of chlorine atom from photolysis of ClNO2in the early morning exceeds the production of hydroxyl radical via ozone photolysis by several factors.Therefore,ClNO2plays an important role in jump-starting the atmospheric photochemistry in polluted marine boundary layer of southern China.
