TOPOGRAPHIC OBSERVATION OF THE TIDAL FLAT AT THE MOUTH OF THE SHIRAKAWA RIVER DURING THE PASSAGE OF TYPHOON NO.9 AND NO.10 USING OPTICAL FIBERS

Abstract

The authors developed a new method for long-term and high frequency measurement of tidal flat using optical fibers and conducted continuous observation from October 2019 and March 2020, confirming the validity of the optical fiber observations. In September 2020, typhoons No.9 and No.10 approached the observation site. Typhoon No.10 was said to be one of the largest and strongest typhoons on record, and an emergency warning was launched. In this study we focused on the periods before and after these typhoons to clarity the validity of this observation method and the tidal flat topographic response during typhoon.