Abstract
Aerosol Concentration observations were conducted every second month from August 1990 to February1992 at Tsushima, Nagasaki Prefecture and Ogori, Fukuoka Prefecture. Data included sulfate, nitrate andother anion and cation species concentrations. Sulfate concentration variations at Tsushima and Ogori hadsimilar changes, and from this fact it can be understood that the life time of sulfate is longer than SO2, andit is a good index of long-range transport (LRT). While nitrate and anmonium concentrations at Ogorilocated in inland took higher values than those observed in Tsushima located isolated in island.
Extremely high concentration episodes of sulfate were found in June 1991 and February 1992. These twoepisodes were analyzed with the help of backward trajectory analysis. It was revealed that the location ofthe rainy season meso-front played a significant role in the transport of pollutants from continental Asia toJapan in June 1991. In February 1992, it was found that the typical winter monsoon weather conditionplayed an important role for the LRT. High concentration of sulfate were observed just after the passagesof lowpressure systems from the East China Sea to the Pacific Ocean. Backward trajectory analysisexplained the observed typical LRT pattern.
These observational and trajectory analysis indicated that the LRT of sulfate from continental Asia toJapan occurred both under the typical rainy season weather condition in June and the typical wintermonsoon season in February.
