Dear authors and reviewers,

First, I’d like to thank both reviewers for their insightful comments, and the authors for their detailed responses. This review process has been highly instructive, and I appreciate the opportunity to engage with a topic I’ve long been invested in—having previously supported the freeze-on hypothesis myself. That said, I agree with Reviewer 1 that the various processes we’ve proposed as potential origins of the plumes likely all play a role to some extent. Let’s hope our models are wrong in the right ways—and still useful!

Turning to the review itself:

Both reviewers and I agree that the science in the paper is sound, that advances the field, and it aligns with the focus of TC.

However, both reviewers point out that the model assumptions, rheology and boundary conditions, require further discussion. Their suggestions are clear and constructive, and I believe addressing them will significantly strengthen the manuscript. Additionally, the reviewers have provided numerous specific comments that will help improve the clarity of the text. I ask the authors to respond to these suggestions in a point-by-point manner, with the aim of enhancing both the clarity and the interpretation of the results.

Given that some of the general comments touch on the interpretation of the main findings, I will be asking the reviewers to check the updated paper.

Carlos Martin

Dear Authors,
Both reviewers agree that most of their concerns have been addressed. We all agree that the manuscript has improved significantly and is now close to being ready for publication.
Reviewer #1 has provided a few suggestions that do not involve additional modelling, and I believe these would further strengthen the paper. I encourage you to consider including the time-series figure in the manuscript and expanding the discussion on the temporal evolution of the model, as Reviewer #1’s arguments on this point are compelling. Additionally, Reviewer #1 recommends further discussion of the discrepancy between modelled and observed velocities in regions where plumes are present. I agree that this issue needs more discussion.
Best regards,
Carlos Martin

Dear authors,

Thank you for addressing the final suggestions from reviewer #1. This has been an instructive and genuinely enjoyable review process.

I was even tempted to seek further comments from the reviewers, but I believe the paper is already clear, engaging, and fully ready for publication. It also opens a new door for future research in this area.
With best regards,

Carlos Martin