Using a cloud-resolving atmosphere-ocean coupled model - Weather Research and Forecasting (WRF) in conjunction with the Regional Ocean Model System (ROMS), this study quantitatively assesses the aerosol microphysical effects and aerosol-modified ocean feedbacks during Hurricane Katrina. It highlights the importance of accounting for the effects of aerosol microphysics and ocean-coupling feedbacks to improve the forecast of TC destructiveness, particularly near the heavily polluted coastal regions along the Gulf of Mexico. Thus, I think it is worthy for prompt publication with minor modifications.

Line 51, “increasing” should be “increase”?

Line 57-59, Observational studies that aerosols modify the generating environment of TCs could be also mentioned here, such as that over Atlantic region by Sun and Zhao (2020, doi: 10.1029/2020JD033454).

Line 69-70, moving “models” behind “most operational forecast”?

Line 245, “enable” should be “enables”

Line 264, “is” should be “are”?

Line 434, What do the authors mean “evidence in by …”?

In this study, the authors perform a set of experiments using the fully coupled WRF-ROMS to understand the effect of aerosols on Hurricane Katrina. The results are quite interesting and the authors examine multiple aspects of aerosol effects on the storm. The main takeaway is that the storm gets weaker in its inner-core, but precipitation is enhanced, especially away from the storm center. They also conduct some mechanistic analysis to explain their results. Overall, I like the study and believe it’ll be a good contribution, provided they address a few concerns listed below.

Line 20: I would just call them intense storms. The phrase ‘with a high Saffir-Simpson scale’ sounds a bit strange.

Lines 80-86: Ekman upwelling is only important for slow moving storms. The main reason for sea surface cooling under TCs is vertical mixing.

Although there is some uncertainty in the aerosol effect on TCs, some previous work has been done to address this that must be acknowledged (eg. Souri et al. (2020))

Is there a reason why the authors chose the case of Hurricane Katrina for this study? Considering that there have been other impactful storms in the Gulf more recently (eg. Harvey), I wonder what the motivation might be to pick this particular storm.

Lines 234-235: I’m not sure this is the correct interpretation. When the storm moves slowly, cooling is enhanced due to more sustained mixing and upwelling.

Lines 256-258: Is the storm dissipation stage related to landfall? If so, how can ocean coupling affect the storm when it is interacting with land?

Lines 282-284: Are we saying that under aerosols, the storm produces more precipitation despite being in a weakened state?

Section 3.3: While the effect of aerosols on precipitation is more straightforward to understand, the impact on storm surge is less clear. Surge depends not just on the intensity of the storm, but also on the orientation of the winds relative to the coastline. In other words, the integrated kinetic energy could be a metric of the destructive potential, but its direct relevance to storm surge is unclear. On the other hand, the examination of sea-level heights is a step in the right direction. Can you also plot the wind vectors in the right column of fig. 9? It’ll be interesting to understand the alternating high and low sea-level anomalies near the Mississippi-Alabama coast.

Lines 387-397: Can aerosols directly affect SSTs through a modulation of the cloud radiative feedbacks? In other words, what is the effect of the aerosols on the pre-storm environment?

The radial profiles of wind stress (Fig. 12) show that in the aerosol case, the peak winds shift farther from the center. Does it mean that the hurricane eye tends to be larger in the presence of aerosols.

Finally, how much can we generalize based on this case study.