Abstract
In recent years, the increasing photochemical oxidant concentration in Japan has been discussed as one of the social issues. In the Kanto area in the summer, the effect of transboundary air pollution is not very high, therefore, a domestic pollutant source could effect this issue. Based on previous studies, a high concentration of inland ozone results from the transportation of ozone from the south, the Tokyo Bay area and the Pacific Ocean driven by sea breezes. However some studies have shown that a high concentration of ozone was observed in the northern Kanto area, before the ozone from south arrives. To understand this ozone elevation in the northern Kanto area, we consider the contribution of the upper-layer ozone to the ground-level ozone by a box model with no chemical reactions. The difference between the simulated results and observed results at 12:00 is 30-60ppb. This difference would be caused by chemical reactions. From the doppler lidar observations and observations of the ozone concentration at Mt. Akagi, the ozone concentration was almost constant and about a 4 to 5 m/s horizontal wind blew on the night of July 27th and August 4th at a 1300m height. These results would mean that the northern Kanto area was covered by a constant concentration ozone and transported by the wind.
