[M-AG33] Basic study on the estimation of the "Black Rain" area caused by the atomic bomb

[MAG33-07] Numerical Model Construction for "Black-Rain" Reproduction Run

*Kunio Takahashi¹, Takayuki Tomizuka¹, Yasuhito Igarashi², Hirohiko Ishikawa², Masayuki Takigawa³, Tetsuji Imanaka² (1.AdvanceSoft Corporation, 2.Institute for Integrated Radiation and Nuclear Science, Kyoto University, 3.Japan Agency for Marine-Earth Science and Technology)

Keywords:Black-Rain, Weather Research Forecasting Model, Lagrangian Transport and Dispersion Model , ERA5

We attempted to reproduce the meteorological conditions after the atomic bombing of Hiroshima, the diffusion and deposition of radioactive materials due to the nuclear explosion, and the effects of a large-scale explosion and urban fires on the meteorological conditions using a state-of-the-art meteorological model. The temperature distribution after the atomic bombings and the amount of Cs-137 generated based on the mass fraction of the material originating from the atomic bombs were obtained from the explosion model. The advection-diffusion and deposition calculations were conducted in the meteorological field calculated by WRF (Weather Research Forecasting model, version 4.4). The effects of urban fires, cumulus development, precipitation and deposition were incorporated into the WRF. We investigated the effects of explosions and fires on the reproducibility of black rain and the dispersion of radioactive materials by using the FLEXPART (FLEXible Particle Dispersion Model, version 3.3.2) model.