阪神地方のメタンの分布・発生について

Abstract

The spatial distributions of methane over Hanshin district (Osaka, Kobe andneighborhood) in cold season were observed, when the release of methane due tothe biosphere such as lakes, marshes and rice fields was negligible. Air sampleswere collected on an aircraft and on the ground in early morning and afternoon.The concentration of methane was determined by gas chromatography in thelaboratory.During observations the temperature inversion persisted at the altitude of 1.5-2.0 km through which the upward transport of methane was negligible. Below thatlayer high concentration of methane was observed with the maximum methanemixing ratio over the central part of Osaka City. The methane flux from thesurface was estimated to be 0.27 g/m2/day in the central part of Osaka City, whichis comparable with the most intense flux from the ecosystems or vegetation such aslakes, marshes, or rice fields.