[HTT19-P09] Analyzing short-term topographic change in coastal sand dunes using UAS-SfM photogrammetry: A case study in Northern Kujukuri, Japan
Keywords:GIS, Coastal sand dunes, UAV, SfM
UAV-SfM surveys were conducted seven times from September 2016 to December 2018, and the obtained topographic data were analyzed using GIS software (ArcGIS Pro) to evaluate changes in terrain conditions by season and year. We also analyzed the wind direction data provided by the Japan Meteorological Agency. Vegetation data were obtained from the field surveys and the green-red vegetation index extracted from the UAS images. The following three characteristics were identified: 1) Short-term topographic changes tend to be influenced by specific events such as storm events, and therefore terrain conditions in the same season may be different from year to year. 2) General wind conditions represented by the meteorological data corresponding to the overall change of sand dune topography, especially at seasonal or longer scales. 3) Formation of small sand dunes is affected by vegetation distribution. This study has suggested factors affecting short-term topographic changes of coastal sand dunes based on frequent data acquisition in the field and geospatial technologies.