Dear Michael Studinger and co-authors,

Thank you for submitting your responses to the referees' reports. Based on the changes you have outlined in the response, I encourage you to submit a revised version through the Copernicus system. In the new version of the manuscript, I ask you to consider the following points:

- Clarify in the paragraphs discussing dune migration (lines 252-253) that the rate of movement of the dunes described by Fahnestock cannot be transferred directly to your study area (e.g. different setting/area). In other words, that the cited 60 m in 34 years is just an example of what the rate might be.

- Please include a brief explanation of the artefacts in Fig 5.

- I agree with reviewer 2 that a slightly longer explanation is needed to understand the reason for assessing the correlation of the standard deviation (lines 391-409).

- Fig. 3/line 239: add an arrow to Fig. 3 showing where the area is located

- lines 362-363: Since you do not calculate r2-values, please clarify if this correlation is based on visual inspection of the plots in Fig. 6, or if it is an established correlation from previous work (then cite relevant literature)

- line 393: consider using "match" instead of "correlation" to avoid implying a statistical analysis.

- In the response to referee 2 regarding lack of citation to previous, potentially relevant, surface accumulation/roughness investigations it is stated that: "Our paper describes spatial variations in accumulation rates and does not focus on absolute values, because there are no existing data that we could use to tie our radar-derived accumulation rates to firn cores or snow pits in the area."
There might not be any temporally overlapping datasets but investigating some of the literature suggested by the referee reveals that accumulation rates exist from the traverses conducted in the 1960s. For example, measurements from 1962/63 traverse (partly following 88S) showed accumulation rates of around 8g/cm2. This dataset also relates to a comment by referee 1 regarding annual layers: The 1962/63 data show 8 years are present in a depth interval of 25-190cm. See https://agupubs.onlinelibrary.wiley.com/doi/10.1029/AR016p0209 (Taylor)
A study from the same issue of Antarctic Research Series notes that: "Detailed profiles reveal topography of the order of 10 to 30 meters in amplitude with half-wave-lengths of 10 to 30 km. Superimposed on these are features generally 2 to 4 km in extent and with up to 6 or 8 meters of relief." https://agupubs.onlinelibrary.wiley.com/doi/10.1029/AR016p0039 (Beitzel). While the amplitude is different from the numbers you report, this could be an early mention of megadunes.
Finally, an earlier study by Lister and Pratt (https://www.jstor.org/stable/1791117) note the dominant direction and mean height of sastrugis measured in 1957 during an expedition crossing 88S. Again, I acknowledge that the data are not temporally overlapping with your observations but a short sentence mentioning the similarity/dissimilarity with your results would be very interesting, and at the same time demonstrate the long-lived interest in surface roughness investigations.

I look forward to reading the new version of the manuscript and in particular to seeing how you have addressed the comments from reviewer 2 regarding structure.

Best,
Nanna B. Karlsson
Scientific editor

Dear Michael Studinger and co-authors,

Thank you for submitting the revised manuscript. In particular, thank you for clarifying that you did consider the observations from the 1960s but that the quality was too poor for comparison with your work.
I have no further comments (except for two very minor one, see below), and I am happy to recommend the manuscript for publication.
Best,
Nanna B. Karlsson, handling scientific editor

Comments:
Line 36: Is there a word missing? "The southern convergence of all Ice, Cloud, and land Elevation Satellite-2 (ICESat-2, (Markus et al., 2017)) and CryoSat-2 (Wingham et al., 2006) ground reference tracks at 88°S (McConnell et al., 1997; Mosley-Thompson et al., 1999; Winski et al., 2019, Helm et al., 2014)."

From previous editor report: "Fig. 3/line 239: add an arrow to Fig. 3". This is a suggestion to add an arrow indicating where the smooth area located between 175° W and 60° E can be seen on Figure 3. The comment relates back to the difficulty in coupling the information shown in Fig. 3 with Fig. 4. You have already discussed this in your reply to reviewer 1, and I agree with you that regardless of coordinate system it will always be challenging when features cross the 180W/180E line. If you prefer to not annotate your figures further perhaps you can specify somewhere (either in the text or in the figure caption) that Fig. 4 starts at Titan Dome and moves clockwise along 88°S.