title: Deposition of 137Cs in Rokkasho, Japan and its relation to Asian dust.
abstract: Biweekly atmospheric depositions of (137)Cs were measured in Rokkasho, Aomori, Japan from March 2000 to March 2006 to study recent (137)Cs deposition. Although the deposition level was generally lower than the detectable limit, deposition samples collected in spring occasionally had measurable levels of (137)Cs. The annual (137)Cs deposition from 2001 to 2005 was 0.04-0.69 Bq m(-2) with a mean value of 0.27 Bq m(-2). Depositions of insoluble Al, Fe and Ti were strongly correlated with the (137)Cs deposition, suggesting that suspension of soil particles was the main source of the recent (137)Cs deposition. Asian dust events were coincident with some of the significant (137)Cs depositions in spring. It was found that the ratios of (137)Cs/Al and Fe/Al could be used as indices for discriminating Asian dust from suspension of the local surface soil. Backward trajectory analysis suggested southern Mongolian and northeastern China regions as sources of the significant (137)Cs depositions.
authors.affiliation: Department of Radioecology, Institute for Environmental Sciences, Rokkasho, Aomori 039-3212, Japan. nao@ies.or.jp
authors.forename: Naofumi
authors.initials: N
authors.lastname: Akata
authors.forename: Hidenao
authors.initials: H
authors.lastname: Hasegawa
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Kawabata
authors.forename: Yuki
authors.initials: Y
authors.lastname: Chikuchi
authors.forename: Tadahiro
authors.initials: T
authors.lastname: Sato
authors.forename: Yoshihito
authors.initials: Y
authors.lastname: Ohtsuka
authors.forename: Kunio
authors.initials: K
authors.lastname: Kondo
authors.forename: Shun'ichi
authors.initials: S
authors.lastname: Hisamatsu
mesh_terms: D000396:Air Pollutants, Radioactive / Q000032:analysis*; D000535:Aluminum / Q000032:analysis; D001272:Atmosphere / Q000032:analysis; D002588:Cesium Radioisotopes / Q000032:analysis*; D004391:Dust / Q000032:analysis*; D007501:Iron / Q000032:analysis; D007564:Japan; D011834:Radiation Monitoring; D011847:Radioactive Fallout; D014025:Titanium / Q000032:analysis
chemical_list: D000396:Air Pollutants, Radioactive; D002588:Cesium Radioisotopes; D004391:Dust; D011847:Radioactive Fallout; D000535:Aluminum; D014025:Titanium; D007501:Iron