Dear Ward and Thomas,

thank you for sketching a detailed path for how you intend to address the comments provided by the two referees.
As far as I am concerned, the replies sound all reasonable and I thus invite you to submit a manuscript version that has been revised accordingly. In particular, I think that your argument for why different methodologies (IGM and PISM) are used for different glaciers is defensible. Beyond that, I appreciate the efforts in taking into account the various, constructive comments that were provided.

Once uploaded, the revised version of your article will be sent out to the same two referees. I hope that the article can then be finalized soon after this step.

Best wishes
Daniel Farinotti

Dear Ward and Thomas,

Your revised version of the manuscript has now been re-seen by the two referees that commented upon the first submission.
While one reviewer is fully satisfied with your revisions, the second reviewer is left with some concerns. In particular, the reviewer still asks for a more detailed justification for the application of different methods to different type of glaciers.
In my opinion, expanding on the argumentation that you presented within your rebuttal letter and making sure that the argumentation is directly included in the manuscript (as opposed to leaving it in the rebuttal letter only) should help in resolving the situation. The other points risen by the reviewer, notably addressing the value of the new results and the use of the perfect plasticity method, seem easier to address.
Overall, I perceive the comments of the second reviewer as being both constructive and understandable, which makes me confident that the manuscript can be successfully finalized. The decision will thus read “Publish subject to revisions”, meaning that your answers will be re-seen by both me and the referee.

Best wishes and thank you for your work in this matter.
Daniel Farinotti

Dear Ward and Thomas,

I am pleased to inform you that your latest revision of your manuscript is now ready to be accepted for publication. The decision “Publish subject to technical corrections” is meant to provide you with the opportunity of addressing the point below.

The referee is left with a small concern regarding the way you compute the metrics used for the PISM vs. IGM comparison on small glaciers, and I leave it up to you if you can address this concern or not. In case you do, please directly perform the necessary changes in the manuscript, as there is no need for a further rebuttal letter.

From my end, I was wondering if you considered replacing the word “bed” with “subglacial topography” in the manuscript’s title. The latter option might be slightly clearer, and better align with the wording you use in the abstract (e.g. Lines 1+4) and elsewhere. Also in this case, I leave the final decision up to you.

Finally, I have the following two, minor remarks:
- Line 9 (and possibly elsewhere): please clarify that Kvitøya is an island – this will likely be of help to readers that are not familiar with the region of interest.
- Please carefully check your reference list. I noticed, for example, that the entries for Bintanja et al. (2013), Nuth et al. (2013) or Serreze et al. (2011) lack an article number; that Friedl et al. (2011) or Fürst et al. (2018a) are not specified of being “data sets”; or that Cook et al. (2023) has a different title-capitalization style than other reference.

Best wishes.
Daniel Farinotti