[MAG44-01] Sensitivity study of models and meteorology for local-scale radionuclide transport in the Fukushima Daiichi accident
★Invited Papers
Keywords:radionuclide transport, nuclear accident, atmospheric dispersion, meteorological data sets
A large number of radionuclides were released into the environment following the Fukushima Daiichi Nuclear Power Plant (FDNPP1) accident on March 11, 2011. It is important to study the behavior of radionuclides in air, for mitigating the environmental pollution and reducing the health hazards. In this study, sensitivities of local-scale radionuclides transport to three different meteorological data sets and two air dispersion models were studied to obtain the optimal meteorological input. Three meteorological data include the 1km-assimilation meteorological data, 3km-unassimilated meteorological data, and onsite measured weather data. The Lagrangian particle model (Micro Swift Spray: MSS) and the Lagrangian puff model (Risø Mesoscale Puff model: Rimpuff) were used to investigate the behavior of models of different mechanisms for this scenario. Measurement data of two near-field monitor posts were used to validate the simulation results. The analysis shows that most combinations of the involved meteorology and models can reproduce peaks of the measured data. But the timing of the concentration peak shows more deviations in the MSS simulation than in the RIMPUFF simulation. And the onsite measured weather data provided more details of simulated results than other meteorological data sets. However, Rimpuff simulation with onsite measured weather data may reproduce an artificial peak of concentrations that is not obtained by any other scheme.