A study on the impact of meteorological factors on radioactive fallout predictions of nuclear explosions

By designing several sets of sensitivity experiments with varying meteorological factors, this study investigates the influence of precipitation and wind speed variations on the radioactive fallout predictions based on the WRF-NAQPMS nuclear explosion radioactive fallout prediction model with its flexible meteorological data interface module. The results indicate that in the high precipitation scenario, although the instantons ground dose rate decreases 1 h after explosion, the cumulative ground dose rate increases with increasing precipitation 12 h after explosion. The total ground fallout reaches saturation for refractory nuclides, but shows slowing growth trend for volatile nuclides as precipitation intensity increases. Variations in wind speed have a significant impact on both the ground and vertical distribution of dose rate. The ground dose rate increases with decreasing wind speed, the vertical range of altitude layers where radioactive materials accumulate increases, and the altitude at which the high-dose-rate regions occur decreases. Overall, the ground fallout field is most affected by wind speed quantitatively, with a shift in ground dose rate of up to 200.37 % occurring within 12 h after explosion. Within 1 h after explosion, the ground dose rate fluctuates between 3.82 % and 20.63 % due to precipitation variations.