ANALYSIS OF MAIN FACTOR IN REGIONAL SEA-LEVEL VARIABILITY DUE TO CLIMATE CHANGE AROUND JAPAN

Abstract

 This study aims to identify the main factor of sea-level change around Japan. In order to consider climate change that occurs on various temporal and spatial scales, we analyzed three different types of the dataset; tide gauge observation around Japan, sea-level projection by the MIROC6 global climate model (100 km horizontal resolution), and ocean reanalysis data by FORA-WNP30 (10 km horizontal resolution). Besides, we simulated ocean circulation at a 20 km horizontal resolution using ROMS model. From the result of MIROC6 analysis, we revealed that 70 percent of the component of dynamic sea-level change around the North Pacific is caused by ENSO. Moreover, the amplitude of the variability is 10 cm. On the other hand, analysis of high-resolution data showed that sea-level variability near the Japanese coast is dominated by the phenomenon which occurs on a coastal scale, and the maximum amplitude is around 5 cm.