Dear authors

I will accept the publication of your MS once the second round of review by Prof. Matsuoka is taken into account.

I have reproduced below hiz comments

Reviewed by Kenny Matsuoka

The revised manuscript is substantially improved from the earlier version and responses to reviewers’ comments are mostly satisfactory. Below, I made a few more additional suggestions to improve the manuscript.

1. Balance velocities are used as a criteria to define Oldest Ice candidate sites. Are balance velocities re-calculated using the new ice thickness map, or is it adapted from the previous work? Also, how is the shape function (vertical variation of flow speed) assumed? I understand that details are given in Van Liefferinge and Pattyn (2013) but this aspect should be more described. I recommend a new supplemental figure showing the balance velocity (or zoning of < 1 m/a, 1-2 m/a, or > 2 m/a).

2. Delta G are not shown for significant segments of the presented flight paths, e.g. Figs. 5, S3, S4, S5. Figure S5 caption says that Delta G is smaller than the threshold (5 mW/m2), but no explanations are given for the other regions. Why are dG not shown here? If the balance velocity is larger than the criteria, I rather recommend to show dG regardless of the balance velocity but use a different legend (e.g. solid curve if balance velocity is less than 2 m/a, but dashed curve if the speed is larger).

3. Fig. S4 give an interesting insight; dG is ~8 mW/m2 whereas the radar echo shows flat, smooth, and strong echo, a typical indication of the lake. Does it mean that dG has an uncertainty of ~8mW/m2 generally in the study area, or is it more site specific? Fig. S4 shows the data from the furthest location from the dome and I assume that flow speed is rather large there and thus model assumptions are not fully valid. I think that some interpretations of this feature, lake at large dG, give more value to this paper.

4. At the bottom of P.8, the authors argue that the western region (76S, 30E) is no longer hopeful. However, the areal difference between the previous and new studies seems not so large; the area reduced about 20% by area but still significant part of the region is still predicted with large dG. I agree with the authors that the flow speed is large and bed is rough there but still I feel that it is too premature to exclude this region from future research. In any case, please write more to support this assessment or tone down the assessment.

5. Please clarify further that temporal resolutions of the prospective ice core are not quantitatively evaluated in this analysis. It is said qualitatively (e.g. thin ice brings low time resolution) but no quantitative analysis is made here and it is left for future research.

Minor points:

P4L30-33: I think that it is an interesting observation but the description is too brief to make a solid conclusion. If possible, please calculate the standard deviation for different angle ranges between flight paths (e.g. 0-30, 30-60, 60-90). The standard deviation seems quite large here, as both datasets are collected very recently with high position and ice-thickness accuracy. Bed slope may be an alternative explanation of this large discrepancy.

P10L13 I think that 35 km is a typo. Note that Figure 6 cation (p11, 2nd line from the bottom) says that it is 2.5 km.

with regards