報告書番号

283027

タイトル（和文）

オキシダント濃度に及ぼすバックグラウンドオゾンの影響

タイトル（英文）

THE IMPACT OF BACKGROUND OZONE ON THE GROUND-LEVEL OXIDANT CONCENTRATION

概要 （図表や脚注は「報告書全文」に掲載しております）

１９８２年８～９月，伊豆諸島から関東内陸においてオゾン濃度の観測を実施し，首都圏のオキシダント濃度に及ぼすバックグラウンドのオゾンの影響について検討した。その結果，当該期間のバックグラウンドの濃度を２０～２５ｐｐｂ，オキシダントの環境基準６０ｐｐｂを超える高濃度発生時にバックグラウンドが占める割合を３０～４０％と評価した。この割合は，低気圧性攪乱の後面では増加することがあった。

概要 （英文）

MEASUREMENTS FOR OZONE CONCENTRATIONS WERE MADE AT URBAN AND NONURBAN SITES IN KANTO DISTRICT DURING AUGUST TO SEPTEMBER 1982. THE CONTRIBUTION OF BACKGROUND OZONE TO THE GROUND-LEVEL AIR QUALITY IN THE METROPOLITAN AREA WAS DISCUSSED ON THE BASIS OF THE DATA OBTAINED. TYPICAL MEAN OZONE LEVELS OF 20 PPB WERE MEASURED AND THE CONTRIBUTION OF BACKGROUND OZONE ON THE GROUND-LEVEL OXIDANT WAS EVALUATED 30-40% HERE IN THE AUGUST TO SEPTEMBER PERIOD. METEOROLOGICAL ANALYSIS SUGGESTED THAT INTRUSIONS OF OZONE FROM STRATOSPHERE TO LOWER TROPOSPHERE TOOK PLACE BEHIND CYCLONIC DISTURBANCES. HOWEVER,HYPOTHESIS THATSTRATOSPHERIC OZONE CONTRIBUTE LARGE AMOUNT OF OXIDANTS IN URBAN ATMOSPHERE COULD NOT BE SUPPORTED FROM THE ANALYSIS. DIURNAL VARIATIONS OF OXIDANTS IN URBAN ATMOSPHERE COULD NOT BE SUPPORTED FROM THE ANALYSIS. DIURNAL VARIATIONS OF OXIDANT CONCENTRATION WERE NOT PRODUCED BY THE INTRUSION OF STRATOSPHERIC OZONE BUT BY THE PHOTOCHEMICAL REACTION NEAR THE GROUND. HIGH OXIDANT EPISODES TOOK PLACE WITH NO RELATION TO BACKGROUND OZONE LEVELS IN THE URBAN ATMOSPHERE.

報告者

キーワード