**5. Conclusions**

This study evaluated the performance of multiple SPPs (including TRMM7, IMERG5, IMERG6, and GSMaP7) in depicting the variations of summer precipitation over Taiwan. The evaluations were performed at mean status, daily, interannual, and diurnal timescales. The major goal was to clarify whether IMERG6 is the best choice to replace TRMM7 for studying the summer precipitation variations over Taiwan. In addition, capabilities to apply SPPs in studying the most frequently observed weather pattern in Taiwan, that is, CAR event, is also examined. The performances of SPPs were evaluated using more than 400 gauges (i.e., CWB data) in Taiwan as the reference base for comparison.

Our analyses show that IMERG6 overall outperforms the other SPPs for depicting the spatial-temporal characteristics of summer precipitation over Taiwan varied at multiple timescales. Among the four SPPs, IMERG6 also has the smallest bias in depicting the characteristics of CAR activities in Taiwan. All the above findings suggest that more accurate results can be obtained if IMERG6 is used to replace TRMM7 for studying issues that are related to the summer precipitation in Taiwan. It is noted that above statement is true for the time period between 2000 and 2017. Further studies are suggested to evaluate the performance of multiple SPPs in Taiwan during the dry seasons.

Additionally, when investigating the differences between TRMM7 and the other SPPs over the Asian domain, we note that IMERG5 (GSMaP7) has the largest difference to TRMM7 over the ocean (land). This finding provides useful information for future studies that tend to use GPM products to replace TRMM7 for estimating the moisture budget over the Asian domain e.g., [49–52].

**Author Contributions:** Conceptualization, W.-R.H.; Data curation, W.-R.H., P.-Y.L. and Y.-H.C., Investigation, W.-R.H.; Software, P.-Y.L. and Y.-H.C.; Writing—original draft, W.-R.H.; Writing—review & editing, W.-R.H., P.-Y.L., Y.-H.C. and C.-Y.L. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by the Ministry of Science and Technology of Taiwan under MOST 106-2628-M-003-001-MY4 and MOST 108-2625-M-003-004. CYL was supported by MOST 107-2111-M-008-034 and MOST 108-2625-M-008-015.

**Acknowledgments:** We thank the provider of TRMM, IMERG, GSMaP, and CWB data.

**Conflicts of Interest:** The authors declare no conflict of interest.
