Abstract
The concentration of ozone and nitrogen dioxide in the surface air in Tokyo area was observed at two stations respectively in the suburb and the midtown.
The results of ozone determination observed at the suburban station showed a seasonal variation with the maximum (29μg/m3) in April and the minimum (14μg/m3) in October. Day-to-day variation of ozone at the midtown area is closely correlated to that at the suburb and daily mean values in summer are higher at the former than the latter. This excess ozone was explained taking the seasonal variation of the air pollution into consideration. The ozone formation in the midtown area of Tokyo is quite probable. The concentration of nitrogen dioxide at the midtown area is about 2.5 times greater than that at the suburb and the maximum values were observed in winter season at both stations. In addition, the effects of SO2, NO2 and nitrate on the determination of ozone were examined. The results showed that SO2 is the most disturbing agent in the air of Tokyo.
