Dear Dr. Robel and co-authors,

Regarding your paper submission tc-2016-18, "Persistence and Variability of Ice Stream Grounding Lines on Retrograde Bed Slopes," many thanks for your work on this so far.

I thank you for already having posted your responses and revisions to the paper online on the TCD page for the paper. I consider that you have engaged very well with both reviewers' sets of comments, though I would like to ask one of the reviewers to make a further assessment of the revised manuscript.

To take the paper further, I now ask you to submit your revised paper and responses to reviewers to me following the instructions associated with this email. For clarity, (i) you MUST do this as an additional step to having already posted your response publically (this is to do with the way the copernicus system operates, but (ii) in your case this is likely simply to be a case of forwarding the responses you have already posted online, but just in case there is anything else you would like to add, you also have an opportunity to do so at this stage.

I look forward to being notified of you completing this next, hopefully very rapid, step.

Very best wishes,

Rob

Dear Dr. Robel and co-authors,

Regarding your paper submission tc-2016-18, "Persistence and Variability of Ice Stream Grounding Lines on Retrograde Bed Slopes," your paper has now been re-reviewed by one of the original reviewers. That reviewer appreciates that you have made most of the suggested revisions, but has raised just a few further issues to which I will need to see your responses before taking the paper further.

The referee's report should be accessible from this message; if not please let me know by return message.

Just as you did in response to the first round, please respond with a rebuttal letter and a revised version with the changes highlighted.

As the reviewer has highlighted that the suggested changes this time round do not necessarily define whether the paper should be published - rather they are suggestions for its improvement - it is my hope that this next stage should not to be too onerous to complete.

I look forward to seeing your response in due course.

Very best wishes,

Rob

Dear Dr. Robel and co-authors,

Thank you for re-submitting your revised manuscript and responding in full to the second review.

I am now almost ready to accept your manuscript. In my final readthrough, I found the paper, in general, very well written (and certainly very interesting) but picked up a handful of minor grammatical issues, appended in the attached.

I would also ask you to consider the use of hyphens in, for example, "ice stream", "ice sheet" and "grounding line" whenever these terms are used as prepositions, i.e. one can discuss the case of an ice stream (no hyphen) versus ice-stream processes. I corrected these cases in the abstract (and the paper title!), but request that you use a find/replace exercise to correct this through the manuscript.

Apologies for these final, very minor issues, but I am sure you will them very simple to implement. When you're done, just follow the instructions for resubmitting appended to this message, and I should be in position to accept the manuscript.

Very best wishes,

Rob B

Dear Dr. Robel and co-authors,

It is my pleasure now to accept your manuscript for publication in The Cryosphere.

I would like to thank you for submitting this very interesting and well written manuscript. I would also like to thank both reviewers for their thorough work and incisive comments, and you in turn for responding to these comments with appropriate revisions.

Many thanks again for submitting your work to The Cryosphere,

Very best wishes,

Rob B