Thank you for your detailed and thorough response to the review comments. Please proceed with submitting your revised manuscript.
Chris Derksen

Thanks to author team for responding so thoroughly to the reviewer comments. This is an important paper, which provides a comprehensive inter-comparison and evaluation of contemporary satellite-derived sea ice products for both the Arctic and Antarctic. A substantial amount of analysis is presented, but the writing is now more succinct, and the communication/presentation of the results is more effective.

I have identified a number of relatively minor changes as outlined below. The only potentially substantive changes that I recommend are to a number of the figures. To me, it makes more sense logically if the datasets are ordered sequentially by Group number (all of Group I followed by all of Group II etc.). This is not the case in many of the figures. In some cases, it only requires a re-ordering of panels, but in some cases figures would need to be re-plotted. I leave it to the authors discretion whether these figure changes are made, but I will note that this is a very densely written paper and so all steps which help the readers interpretability of the results should be seriously considered.

Thanks again for the careful revisions,
Chris Derksen

Line 69: change to “The other kind of algorithm inter-comparison study deals with…”
Line 77: remove the phrase “is relatively old”
Line 85: remove “manual”
Lines 104-110: please ensure all acronyms are defined
Line 109/110: not clear what is meant by “model atmospheres”
Line 157: I understand clearly the importance of 15% SIC for SIE calculations, but perhaps explain briefly how a SIC threshold affects SIA calculations?
Table 2: it makes more sense logically if the datasets are ordered sequentially by Group number (all of Group I followed by all of Group II etc.)
Figures 1 and 2/Figures 6 and 7: can the legend by grouped more clearly and logically around the 4 algorithm group? At present, group I is clear (the 4 products on the right of the legend) but it would the assist the reader if this was more obvious for all 4 groups.
Line 177: I presume the cumulative distribution functions are similar for all years, and 2004 is illustrative? Perhaps note this explicitly?
Line 194: capitalize acronym “Sic”
Line 221-224: define acronyms
Line 241: is the word “own” needed here?
Line 308: change to “Both values are confirmed by Kern (2018)” and include link.
Line 353: change “have been highly unstable since launch” to “were highly unstable from launch”
Figures 8, 10, 11: I suggest ordering the panels by group, so that all group I panels are in sequence, followed by group II, etc.
Figure 8: why is there no summer season SIC difference maps shown for the Arctic as there are for the Antarctic?
Line 365: I think a comma is missing before “…differences can exceed 20%”.
Figures 9 and 12: very helpful to include the algorithm group labels on the y-axis, but why are they ordered I, III, II, IV?
Line 402: “partly substantial” is very vague and unsatisfying wording…
Figure 13 and 14: same comment as for many previous figures – why not order the results sequentially by group?
Line 504: type “fFor”
Figures 15 and 16: I suggest ordering the panels by group, so that all group I panels are in sequence, followed by group II, etc.
Line 701: change to “…just one hemisphere year-round or for an individual season.”
Line 738: change to “…introduces the question and opens the discussion…”
Line 774: change ‘extent’ to ‘extend’