For climate and hydrological research, it is important to explore rainfall variation, as it is closely related to human lives, particularly in the context of economics, agriculture, and disaster prevention (Hung & Shih, 2019). In general, rainfall can be estimated using local rain gauges, radar, and satellite observations (Hsu et al., 2021;Huang & Chan, 2012). However, observations by rain gauges and radars are limited in spatial coverage and observation time (Chen et al., 1999;. In contrast, satellite-based rainfall estimation (SRE) with high spatial coverage can monitor a wider spatial range of rainfall variations Huang et al., 2023). Therefore, SRE is often used for various research purposes (e.g., climate studies, validating model performance, and other studies) (