<添付資料1>船舶レーダによる桜島火山の噴煙柱モニタリング --2018年の観測結果--

Abstract

The present paper describes the results of observational studies of Sakurajima volcanic eruption columns using an X-band marine radar. The X-band marine radar was set up at the Kurokami Observatory located approximately 4 km from the Sakurajima Minamidake vent. We carried out observations by physically changing the rotational axis of the slot antenna, from vertical to horizontal, to achieve an elevation angle resolution of 1.2°. The observation period was from April 11 to May 31, and the collected data was for a total of 57 outstanding eruptions. To our knowledge, our observations represent the first time that marine radar has been used to successfully detect eruptions and falling pyroclastic particles. The radar revealed the fine structure of an ascending eruption column at 1.25-second intervals. The present study demonstrates that eruption source parameters such as eruption onset time, duration, height, and ascending speed can be estimated by marine radar observations.