Dear authors,

Two referees evaluated your manuscript (MS), and I would like to thank both of them for their thoughtful and timely comments. You provided detailed responses and suggestions of how to address the referee’ comments. The track-changed revised MS, added to your responses, shows that you already took into account their comment.

To continue with the publishing process towards TC, I would like to ask you to upload the revised, clean (i.e. not track-changed) MS for a second assessment by me and possibly, the reviewers.

Could you also justify why the velocity bias is provided as an absolute value? Would not it be more relevant to provide signed values so that the reader is able to assess whether the velocities are under or overestimated by each product? I feel it is a key information if users want to use these velocity products to examine temporal change in velocity.

You also took into account most comments from my access review, thanks a lot for that. ITS_LIVE data are now cited/included. I also noted in this access review the existence of velocity maps from Mouginot et al. (cited in your study). Was there a good reason not to evaluate them? Maybe they are simply not available?

I am looking forward to read in detail the revised MS.

Best wishes,

Etienne Berthier

Dear Authors,

I have now read your revised manuscript (MS) and yours responses to the referees. You addressed satisfyingly their comments together with my own ones (from the access review).

I still have a few minor editorial comments before the MS can be published (see below). Thanks for considering them before uploading the final files for copy-editing.

Do not hesitate to contact me if you have some further questions.

Thanks a lot for choosing TC to publish your work.

Best regards,

Etienne Berthier

L46. Is “inferred” needed before mass loss?

L133. “in central flow band wider than 10 km”, add “the” or “a” before “central” (I think)

L166. “optical” better than “visual” imagery.

L167 (here and elsewhere). Space needed between the value and its unit. Check everywhere.

L202. Just 1A? Or Sentinel 1B also? (maybe write Sentinel-1 only?)

L303. “but their standard deviations are much higher due to the SAR processing techniques”. Sorry I did not get your point here because other InSAR based velocity data have a high accuracy and precision. So can you clarify what you mean here?

L316. “quality of the products derived from optical satellite sensors is comparable to data obtained with SAR sensors”. Do you understate “SAR speckle tracking”? Or do you include in this statement all SAR-based velocity fields, including the ones obtained with InSAR?

L420. “The assessment inform of the accuracy” does not sound super idiomatic to me (but I am not native...). Maybe “This study characterizes the accuracy” ?

Figure 6 the red and green dots are hard to distinguished for color blind readers (ENVEO and DTU-Space data points). Maybe show one of them in gray?
Legend: “a linear dependency of the bias”. In fact (I think), it depends linearly on “the inverse of the square root of the temporal coverage” (if needed also apply this correction to the main text, I did not double check).

Figure 8. Try to limit the amount of lot space (white) in this figure. It will gain readability when inserted in the final PDF.

Supp. Fig S2. "Note that" appears more idiomatic to me than "Notice that" (but I am not native).
Ideally add label "EG-S-01" close to the data point in the plot. (otherwise we do not know if this is an outlier in abolute Height or in the the difference between GPS and arctic DEM)