Author(s): Tsuyoshi Hoshino; Tomohito J. Yamada; Hiroaki Kawase
Linked Author(s):
Keywords: Heavy rainfall; Tropical cyclone; Climate change; Large ensemble climate experiment; D4PDF
Abstract: Previous studies have shown that the acceleration of global warming will intensify the intensity of rainfall induced by tropical cyclones (TCs) (hereinafter referred to as “TC-induced rainfall”). TC-induced rainfall is affected by TC intensity, position and topography (slope shape and direction). It means that TC-induced rainfall is expected to vary by sub-basin due to varying topographies. However, relationships between TC intensity, position and topography have not been explained, as historical TCs, which occurred several decades earlier, do not exhaustively encompass all TC intensities and positions that could potentially affect each basin. In this study, we used large ensemble regional climate model experiments with 5 km grid spacing, which enabled us to prepare a huge TC database for understanding the characteristics of TC-induced rainfall over sub-basins. We quantified the characteristics of TC-induced rainfall (relationship between TC position and rainfall intensity, and contribution of TC intensity on rainfall) over two sub-basins in the Tokachi River basin, central Hokkaido, northern Japan. The results reveal differences in TC-induced rainfall characteristics between the two sub-basins. In addition, the large ensemble data under a future climate scenario were used to evaluate future changes in the characteristics of TC-induced rainfall for the sub-basins.
Year: 2020