[2J09-20] 環境放射能

[2J13] 数値シミュレーションに基づく北半球の210Pb沈着量分布

*蔡 宇¹、山澤 弘実²、飯本 武志¹ (1. 東京大学、2. 名古屋大学)

キーワード：大気輸送モデル、Pb-210、Rn-222、自然放射線

To enhance understanding of ²¹⁰Pb deposition distribution characteristics, this study investigated the distribution characteristics of ²¹⁰Pb deposition in the Northern Hemisphere in 2015. Using the WRF and HIRAT models with a 144 km * 144 km lattice size. Our findings reveal a strong correlation between the distribution of ²¹⁰Pb and latitudinal variations, as well as atmospheric circulation patterns. Moreover, we noticed a distinct seasonal variation in the residence time of ²¹⁰Pb in the continental atmosphere, with longer durations during winter and shorter during summer. Notably, we identified a significant source of high deposition in the Sea of Japan region, which is a matter of great concern. Our analysis indicates that this deposition predominantly originates from the continental area upwind.