FAQ/ The inundation depth of the mesh size of 5 m was output even though the analysis was performed with a mesh size of 25 m.¶
From the calculation results of multiple cases, the data of the maximum envelope was exported in MLIT CSV format. Then, even though the analysis was performed with a mesh size of 25 m, the inundation depth with a mesh size of 5 m was output. Why is that?
response¶
Maximum envelope data in MLIT format is output in accordance with the Guidelines for Digitization of Flood Expected Area Map Data (3rd Edition). These guidelines include:
Guidelines for Digitization of Flood Area Map Data (3rd Edition) p. 39
As a general rule, inundation depth (maximum envelope) data (CSV, NetCDF) files shall be stored in a ground height mesh (5 m, etc.).
Moreover, the same p. Table 39, "Elements in Each File," contains the MAXALL. The elements included in the CSV include maximum inundation depth (ground height mesh), elevation, mesh code, and coordinates. Here, the maximum inundation depth (ground height mesh) is the maximum inundation depth converted to 5 m mesh.
From the request of this guideline, MAXALL. The CSV outputs the interpolated inundation depth with a mesh size of 5 m (1/200 standard area mesh to be exact).
As for the depth of inundation enveloping with the mesh (for example, 25 m) used in the analysis, MAXALL_TIME. Please refer to CSV.
For interpolation, ground height data of 5m mesh is used. If the user [Calculation area] has defined > > [5m] , [topography] use that data. Otherwise, it uses DioVSITA's default terrain data.