Measurements of OH reactivity and photochemical ozone production in the urban atmosphere.
Measurements of OH reactivity (i.e., OH loss rates) in the troposphere are essential for discussing tropospheric OH photochemistry. In July and August 2003, we observed the total OH reactivity in a suburban area of Tokyo. More than 90% of the data of the measured OH loss rates were higher than the calculated values with simultaneously measured concentrations of various trace species even though the rate coefficient of the OH + NO2 reaction was measured by us. We concluded that this discrepancy is due to the existence of unmeasured volatile organic compounds (VOCs). We estimated the potential of the photochemical ozone production in the case of including the unknown species as VOCs and excluding the missing sink, respectively. When the unknown species were included as VOCs, the potential increases from 32% to 88%. This result indicates the photochemical production rates of ozone in the urban air are substantially greater than expected.
Sadanaga
Yasuhiro
Y
Japan Science and Technology Agency, 4-1-8, Honcho, Kawaguchi, Saitama 332-0012, Japan. sadanaga@chem.osakafu-u.ac.jp
Yoshino
Ayako
A
Kato
Shungo
S
Kajii
Yoshizumi
Y
D000393:Air Pollutants / Q000032:analysis*; D002947:Cities; D004784:Environmental Monitoring; D017665:Hydroxyl Radical / Q000032:analysis*; D007564:Japan; D009930:Organic Chemicals / Q000032:analysis; D010126:Ozone / Q000032:analysis* / Q000737:chemistry; D010777:Photochemistry; D014835:Volatilization
D000393:Air Pollutants; D009930:Organic Chemicals; D017665:Hydroxyl Radical; D010126:Ozone