The authors have responded well to the three reviews of the a paper. I am satisfied that the scientific concerns raised during review have been dealt with effectively, so no further changes are needed in that respect. However, I think there are a not insignificant number of issues associated with the writing itself that do need to be addressed in order to ensure that the paper can be readily understood by readers. I will append a list of these below (in the form of suggested corrections) and would ask the authors to implement these in a further revision of the paper prior to resubmission. In the event that my proposed changes suggest to the authors that I have misunderstood what they were trying to say, thence can of course discuss alternative wording. It may be easiest to do this offline.

Suggested corrections, keyed by line number in the submitted manuscript:
75: Numerically, these regions…
78: use of the most accurate and highest resolution source data available is….
85: dating from between 1961…
93: in the acquisition dates of…
104: Almost 90% of…
108: approach of Huss….mean glacier thickness…total glacier volume (I would not say “ice” because I think you mean glacier, where the thickness will also include snow and firn)
123: be clear that these spot heights are on rock
130: “average terrain” such as glacier surface topography,
146: these were created by…
176: last few decades.
215-219: the assumed density for volume change may be consistent with that used in other studies – but has it actually be shown to be appropriate in any of these studies – or is it just an assumption?
225: data set of Huss (2012) that provides ….
331: terrain than the recent…
453: meaning of “partly differs considerably” is not clear to me. Do you mean “sometimes, differs considerably” or “can differ considerably” ?
543: Neither mean area…nor mean aspect (r=0.03) were significantly correlated with..
550: “ glacier-specific uncertainties”
557: which correlation is referred to here – not obvious because you refer to multiple indices.
571: I assume you mean that this is expected in a period of climate warming? Please clarify.
577 : which also show…
578: delete “already”
581-584: This sentence is very hard to understand - please rewrite it so that the meaning is obvious.
588: Full stop, rather than colon, to mark end of sentence.
597: in SGI2010
601: Alps for recent years. Carturan….reported an average….
627: methodologies applied contribute to the differences in derived average mass balance. According….
631: “considerably higher” – from this wording, it is unclear whether the accuracy is better or worse over glacierized areas of Switzerland. Please clarify.
636: What does “they” refer to here? Is it “The impacts” in line 633 (which is what the sentence actually says) – or are you saying that the impacts of radar wave penetration need to be considered because penetration can be as much as 10m for SRTM C-band radar (which is what I think you mean). Need to reword the sentence so this is clear.
641: the average 1985-1999 mass balance… and our approach is attributed to…
640-647: This is a very long sentence and after reading it several times I still don’t understand either what it does mean as written, or what it is intended to mean. I have no correction to suggest but one is needed.
648: somewhat higher than values reported…..2014). In addition, preprocessing of the DEM prior to differencing….uncertainty, if the source DEMs…..grid (note spelling error “gird” in your text” cell resolution
656: The quality of both the source DEMs and the glacier outlines used is important, especially if changes…..have to be assessed.
659: (2014) showed….semi-automated….satisfy the requirements for change assessment…
663: “following issues likely also contribute to the differences in….and this study.
667: that neither the mean firn density nor the firn thickness and area changed over the observation period. (But – isn’t it simpler to say the firn mass was constant over the observation period?)
670: firn extent and density have been reported
674: of individual glaciers
679: glaciers in Switzerland
681: ..of the source data explain 17%, differences in the assumptions made regarding the density of volume change 24%, and differences in the quality of the source data used 59% of the difference between the calculated mean mass balances reported here and those reported by Paul and Haeberli (2008).
687: We presented…
689: glaciers in the Swiss Alps
690: What was the source of glacier outlines for the initial period?
692: inventory and compared to…
695: these recently compiled source data of improved quality, we were able to recomputed and extend the ….
700: period. Glaciers still… km3 of this change. Observed ice volume changes were greatest for regions between 2700 and 2800 m a.s.l., and still noticeable above 3500 m a.s.l. No elevation bands with positive elevation changes were identified.
705: photogrammetrically-derived DEMs
706: assessment of the computed volume and mass changes of the glaciers investigated was performed.
708: investigated by comparison of both…
713: to the reference time interval 1980-2010.
715: mass balance for the entire Swiss Alps was..
721: relationship between observed mass changes and topographic factors.
722: differences in glacier hypsometry can partly explain the general pattern of glacier responses to …
726: over the lowermost….
727: for various future…
729: For instance, both mass balance-driven glacier evolution models for the entire Swiss Alps and extrapolations of the measured mass balances of single glaciers to entire catchments can be validated and improved.

Acknowledgements: This study was supported…

Thank you for turning this around so quickly and for the explanation of the changes you choose not to make. I am happy with your reasoning, so conclude that the paper needs no further revision and recommend that it be published in the form now submitted
Best wishes
Martin Sharp