Review of "Large Regional Differences in Antarctic Ice Shelf Mass Loss from Southern Ocean Warming and Meltwater Feedbacks" by Muilwijk et al.

General comment 

In this study, the response of the continental shelf properties to Antarctic freshwater and global warming in a multimodel ensemble is investigated. The response shows a large regionality and this is further used to highlight that for ice loss estimates a regional melting rate should be applied rather than a uniform value. 

The conducted analysis in the manuscript is sound with the shown results, yet the manuscript is very long and contains a lot of details, which leads to the fact that some sections are difficult to follow. Further, some sections would need some more information for clarification.

Overall, I am convinced that this manuscript will be suitable for publication after some revision. I recommend some careful text revision and some improvements on figures below.

Major Comments: 

• Overall, the manuscript is very long, and sometimes the authors explain parts very detailed and do not refer to them later on in the manuscript. E.g., lines 59 - 78 (“isolation” and “homogenization” - these terms are not used in the further manuscript); line 192 (“In addition, future…”  - this sentence does not contribute to the story line and could be removed); line 412 (“ The Amery region…” this information could be interesting; yet it is not used further in the manuscript, so is it important to mention it here?),... I recommended going through the manuscript and revising if all mentioned information is needed to support the main findings of the manuscript. For me the main findings are: the regional changes of freshwater release as well as the importance of a regional melt rate than an Antarctic wide for estimating ice loss. If these are not the desired main aspects by the authors, please make them more clear. 

• Section 2.3.: The authors refer the reader to Zhou et  al 2024a, for more details about climatology. Yet this work is “in prep” and therefore the information about how the data is treated/coverage is not available and makes it questionable. I would recommend some details and maybe plots like the reference field for Figure 5 and 6 in a supplementary material to provide more understanding on how the data is handled and combined.
• Section 2.4 and 2.5: In the current state, the structure is a bit hard to follow, as some parts have been explained in previous parts but other parts are coming later. I would recommend first to introduce how the regional melt coefficient is calculated using the data from 2.5 and then how the basal melt rates are estimated. Further, there is a misbalance between how data is introduced in Section 2.5, where the basal melting  data set is described very detailed and even discussed, while the ice shelf draft is very brief. This makes me wonder, if all the details about the melting data set is needed. Regarding this, it is worth considering if all those details about the data set are a contribution, e.g. the purpose of  lines 296-297 is not clear. Lastly, Table 2 does not exist.
• Sections 4.1 - 4.3: I like the questions asked, yet the answers are not very clear in the respective text. It would be great if the authors could highlight a clear answer to their asked question.  Section 4.3 adds a lot of extra analysis and yet the authors conclude with “However, fully confirming this mechanism requires a detailed investigation of the water mass transformation processes and DSW production, which will be the focus of a future study” (lines 649-651). I am wondering if all of this needs to be detailed in such a long manner. 

Specific Comment:

Line 78-92: I really like these sentences and they are very clear. Maybe it is worth having them as a stand alone paragraph.  

Line 86: It would be helpful if the resolution of the 2 models are mentioned.

Line 138 - 163: I would recommend restructuring these paragraphs to be more reader friendly, the current structure requests the reader to go back and forth between the different paragraphs to understand how the goals, defined in lines 138-143, are tackled.

Line 180: It would be worth stating that these are the same models as in the antwater analysis.

Figure 2: This figure could describe the methodology better, e.g. annotate the arrows by saying which data is feeding into the regional meltwater rate.

Line 195: “Precipitation - evaporation patterns …” - is this based on observations or models?

Line 197: “and some models reroute precipitation over the Antarctic continent directly into the ocean as runoff and/or calving” - this phrasing sparks the question what other models are doing.

Figure 3a and respective lines: The decomposition of the total freshwater fluxes in the SSP5-8.5 scenario in P-E and runoff, shows that there must be a residual term. Which fluxes are represented by the residual? Are those calving and sea ice growth as mentioned in line 204? Please clarify. 

line 231: Please describe the definitions from Barthel et al (2020) not everyone is familiar with them

line 311: What resolution is referred to as “coarse” here, as coarse is a subjective word, it is worth mentioning an order of magnitude.

Line 324-326: Is this general information or pointing to a particular figure? If this is general information, is it needed here as a separate paragraph, otherwise please reference the according figure.

Lines 351- 356: The discussion of the limitations of the climatology without showing the climatology is quite difficult. Please add the climatology, see comment on Section 2.3 above.

Line 363-365: “However, regional…” - the mentioned pattern is not easy to spot in the figures 5 and 6. For me it is only visible in 2 models, the GFDL models, and no common cooling signal in the SSP5-8. 5 simulations. Please provide more guidance where to see this information.

Line 375: “this regime”- it is not clear which regime is referred to.

Line 405: “AWI-ESM…” - there are several models in the right column of Figure 7, which do not show a cooling signal, e.g.: ACCESS-ESM1, CESM2, EC-Earth3. Please revise this statement.

Line 432-435: Based on Figure 8, the intermodel spread is even larger in Amery. Please rephrase.

Line 442: “Some models…”- I would suggest mentioning these models in brackets in the text.

Lines 445 - 455: It is not obvious why some models are described here in detail why others are not. Further there are so many details in this paragraph, which makes it hard to follow. I would recommend revising this paragraph. 

Lines 456 - 458: The purpose of this paragraph is not obvious and needs to be better included with the remaining text.

Line 540-545: Here it is worth reminding the reader that the sectors are shown in Figure 1b

Line 565: Which feedback mechanism? 

Line 616-621: Why is the along slope velocity computed for the upper 500m and the temperature and salinity fields in Figures 5 and 6 in the upper 1000m? “trapped in the boundary” - what exactly is meant? on the shelf or in the ASC? “most pronounced cold anomalies” - AWI-ESM does not show pronounced cold anomalies in Figure 5 second column. Please revise this paragraph.

Figure 5, 6, 9, 13: The use of discrete color levels would improve readability of the values.

Figure 7: Maybe a weak horizontal grey line indicating the +-0.5°C would help to interpret the figure.

Figure 12: What is the reference for the multimodel anomalies? Further, there are 2 annotations marked with * and **, I assume that * refers to the numbers in the different basins, yet what does ** refer to?

Figure 13: Currently, it is quite hard to read the values and compare the circle size changing in between the subplots.

Technical corrections:

Line 172: Reference not included

Line 185: “an observational climatology“ instead of “the observational climatology”

Line 225: Reference not included

Line 277: m is missing the dot above

Line 360: Is Figure 4 here referenced or Figures 5 and 6 ? Please correct either the “s” or the number.

Line 363: “fourth column” —> third column

Figure 8: Add labels a, b, c as the text refers to them.

Line 440:  “second column” —> third column

Line 446: NorESM2-MM —> NorESM2

Caption Figure 10: Formatting of Tf

Line 466: Methods —> which section exactly?

Line 616: Only ASC, it is already introduced