This study applied the numerical simulations of lava flows to evaluate the damage caused by volcanic hazards. The accuracy of the numerical simulation was governed by the reliability of the input parameters in the numerical models. One of the most important parameters is the information pertaining to terrain data, which is generally provided as a digital elevation model (DEM). The recently-developed 8K technology, mainly applied in the broadcasting field, provides a precise photographic survey of the terrain and can produce a detailed digital topographic map. The Japan Broadcasting Cooperation (NHK) deployed an 8K drone to generate a digital elevation model of Sakurajima Volcano, Japan. These data were used to formulate the lava flow under certain prescribed conditions. This study analyzes the influence of DEM mesh size on lava flow simulations, showing that high-precision DEM outlines the distribution of inundated areas in detail. Moreover, a smaller mesh resulted in a faster arrival time of the lava flow. The study’s results are useful for both risk and crisis management.

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