[2J09-20] Environmental Radiation

[2J13] 210Pb deposition distribution in the Northern Hemisphere based on numerical simulation

*YU CAI¹, Hiromi Yamazawa², Takeshi Iimoto¹ (1. The University of Tokyo, 2. Nagoya University)

Keywords:Atmospheric Transport Model, Pb-210, Rn-222, Natural radiation

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.