Please find my detailed review comments in the attached document.

This paper tries to review the unique challenges of floating offshore wind development in Japan towards the large-scale commercialization, which is very important topic. The paper structure needs to be revised slightly, because the earthquake and the Kuroshio Current, which are mentioned in the abstract and conclusion as the uniqueness of Japan, do not seem to be mentioned enough in the main text. 

1. 【Title】The current title may be misinterpreted as a review of researches on floating offshore wind energy system in Japan, but there are few reviews of research papers obtained from the past demonstration projects, and the paper is intended to review what needs to be done towards large-scale commercialization. Just for example, like "Floating Offshore Wind in Japan: Addressing the Challenges, Efforts and Research Gaps towards large-scale commercialization.", some words expressing this aspect are better to be added.

2.  【Section 2.6】This section of metocean conditions should mention about the current, because the authors refer to Kuroshio in the summary section of line1085. The current is also significantly important especially for mooring line design (Also for O&M). 

3. 【Section 2.6.1 line 306】　...stochastic simulations such as MASCTO are widely used in Japan "to consider the effect of typhoon", might be more clear what the authors want to say.

4. 【Section 2.6.3 line 343-345】 The following paper is the outcome from Fukushima FORWARD project about this issue.

• A. Yamaguchi, T. Ishihara, Numerical prediction of Normal and Extreme Waves at Fukushima Offshore Site, Journal of Physics: Conference Series 1037 (4), 042022, 2018.

5. 【Section 3.1.2】Many researches in the demonstration projects in Japan or Norway had big efforts to develop dynamic analysis tool to design the optimum floaters. Just as one example, the latest outcome from Fukushima FORAWRD is as follows. Also there are another papers from Goto project, and Demonstration Project of Next-Generation Floating Offshore Wind Turbine. It might be better to refer these latest efforts relating with design of floaters to address the challenge and efforts in Japan or Norway.

• T. Ishihara, Y. Liu, Dynamic response analysis of a semi-submersible floating wind turbine in combined wave and current conditions using advanced hydrodynamic models, Energies, 13(21), 5820, 2020
• A. Yamaguchi, S. Danupon, T. Ishihara, Numerical prediction of tower loading of floating offshore wind turbine considering effects of wind and wave, Energies,15, 1-18, 2022.

6. 【Section 3.2】The anchor design also is better to be mentioned. "Anchor design against liquefaction due to the earthquake" is one of characteristic of Japan. In Abstract, the authors mention earthquake in line 4, but  there is no specific description about the earthquake in the manuscript. Japan guideline mentions about this liquefaction issue. https://www.mlit.go.jp/common/001331376.pdf

7. 【Section 3.4】This section only has Section 3.4.1. Please check the chapter structure.

8. 【Section 4.2.2】Line 830: The following paper discuss the swell effect on weather downtime in Japan.

• Y.KIKUCHI, T.ISHIHARA: Assessment of weather downtime for the construction of offshore wind farm by using wind and wave simulations, Journal of Physics: Conference Series 753(9) pp.1-11, 2016.

9. 【Figure 7, Line 1211】The uniqueness of Japan found in this paper is difficult to understand from Figure 7. Please consider, if possible.

10. 【Project names】I think that the demonstration project names in Appendix B are not accurate. Please check them. B0.2 →Fukushima Floating Offshore Wind Farm Demonstration Project (Fukushima FORWARD)　B0.3→Demonstration Project of Next-Generation Floating Offshore Wind Turbine (The name of floater is Hibiki, but the project name is different.) 

(【Noticed typo】Line 596: Tow-to-Side → Tow-to-Shore ? / Line 1211: is summarized in 7 → is summarized in Figure 7.)