General comments

In this paper, the authors investigate the effect of horizontal resolution on the North Atlantic mixed layer depth and its link to the AMOC. Their analysis is based on three simulations performed with the EC-Earth3 climate model.

Overall, the paper is well-structured and well-written. The analysis is sound, and results are mainly descriptive. The paper could benefit from a more thorough discussion of the broader implications of the findings.

My comments are mainly orientated to improve the presentation of the results, particularly the figures along with a few minor suggestions to improve the text.

Specific comments on figures

The manuscript includes several geographical references. While some (e.g., Labrador Sea, Irminger Sea, Nordic Seas) are familiar, others (e.g., Cape Farewell, Cape Hatteras) may not be as well-known to all readers. I recommend adding these locations to one of the maps.

F1, F2, FA3. I suggest changing the colorbar of these figures because it is difficult to distinguish the differences, particularly for values below 1000m. Besides, it is hard to see the black line of the climatological sea ice superimposed to the dark contours.

Table 2. I am a bit confused with the information that T2 provides. What exactly does the correlation represent? If it shows the correlation of vertical profiles (model vs. observations), the high values may not be surprising, as they primarily reflect the expected stratification (densest waters at the bottom, lightest at the surface). For instance, the 0.987 correlation for VHR is only a slight improvement over 0.976 for SR. Moreover, visually, Fig. 3a suggests that SR may outperform HR and VHR in some aspects.

F4, F5, F6, F7, F8, FA2, FA5. I suggest plotting dots when the values are significant instead of the other way around.

FA4. The red line in these plots is not distinguishable.

Minor comments and typos

In several places, the cited papers are not properly ordered eg. L48, L64, L65, L76, L194, L238

L13. ‘highest’ instead of ‘higher’

L96-97. Should be: Haarsma et al. (2020) and Moreno Chamarro et al. (2024).

L203. ‘less stratified resolution’ sounds strange to me. I suggest ‘the model version which represents the weakest vertical stratification’.There are other places in the manuscript referring to the model version as resolution alone that can be improved.

L330. ‘highest’ instead of ‘higher’.

L364. ‘partly due to a positive sea ice bias’. This is not actually demonstrated in the current study, but it is so far a hypothesis.

L371-372. ‘A positive NAO phase is found to drive an increase in MLD mixing and the response occurs for negative NAO phases.’ I don’t understand this sentence, please rephrase it.

L375-376. ‘Differences inter-model differences’. Please, delete the first ‘differences’.

L381. What does ‘an almost instantaneous AMOC to mixing, of limited latitudinal reach and persistence’ mean? I don’t understand this sentence.

Please refer to attached file.