2024 Volume 80 Issue 16 Article ID: 23-16002
From the aspect of hydrodynamic, when the atmosphere is unstable, the flow tends to overcome the topography vertically, while when the atmosphere is stable, it tends to avoid the topography and go around it horizontally. In this study, we hypothesized that the more stable the atmosphere is, the more water vapor will be transported to inland, and conducted the sensitivity experiments on atmospheric stability in order to verify the hypothesis. Sensitivity experiments were conducted for the 2012 Kameoka heavy rainfall event, which was caused by the abundant water vapor supplied through the Osaka Bay, then we revealed that the amount of water vapor supplied from the south to inland was greater when the atmosphere was more stable. Furthermore, a cluster analysis of the past atmospheric field was conducted to verify the result of sensitivity experiment results, and it was shown that more water vapor tended to flow inland when the past actual atmosphere was stable. This study provides very important fundamental knowledge for considering the relationship between heavy rainfall and global warming, which has the effect of stabilizing the atmosphere.
