|The number of lines correspond to the revised version with track changes|
General comments :
1) Compared to the first version, this manuscript has been largely improved.
The presentation of data and results is clearer. However, the manuscript needs to be improved again and did not reach the sufficient maturity to be published in TC. Many points need to be clarified. Many sentences are obscure and need to be reformulated (see general and specific comments). Some words are missing. Some words are not English. There are mistakes in some Equations. The authors did not take time to reread thoroughly the revised manuscript. I have the feeling to play the role of colleagues or co-authors to prepare a draft and make a submitted version. Although there are large improvements compared to the first version which was a kind of “technical report”, my feeling is that the authors did not take sufficient time to revise the first version. Could the authors be fair and take pity on Reviewers ?
In any case, this manuscript deserves a publication in TC after the necessary following changes.
2) The results section is not clear enough although that I recognize it has been largely improved. The presentation of the 3 categories is unclear: which difference? Information about the first and the second category is needed. The captions of Fig 5 and Fig 6 are exactly the same and are not helpful. The authors wrote “in similar settings” (l. 12, p. 11) but it is very unclear.
3) Results section: Did the authors remove every measurements where the ice has disappeared between the first and the second measurements? In Figure 4, one can see that the elevation change close to the terminus (altitude close 2880 m, light blue) for the first period, is not very negative (the values are between -5 and 0). It could be due to the fact that the ice has disappeared before the end of the 1st period. If it is the case, the results are biased and the elevation changes are not relevant. It is absolutely necessary to remove these values (Table 3 and Figure 4) to make a relevant analysis.
4) About the results on the third category: The elevation changes for these small features are very heterogeneous. I do not think such data are useful for this paper because the representativeness is strongly questioned. I think that the authors should remove Figure 7 and data of this third category in Table 3.
5) Important: the results are confusing and the reader is lost because the authors wrote everywhere in the manuscript “with mass balance management” for the first period although there is not “mass balance management” during this period except the last years of this period (l. 25, p.4). The authors should reword it because it is very very confusing. For instance, the authors could use “reference areas” and “experimental areas”, and specify “experimental areas without management” for the first period and “experimental areas with management” for the second period….or something else. Check carefully the manuscript. Same thing in captions of Figure 5 and 6. In addition avoid deltaZmbm for the first period in captions of Fig 5 and 6. Change the name of the vertical axis in Fig 5 and 6. Very misleading.
(by the way, Figures 5 and 6 are fine and it is a large improvement compared to the first version).
6) Analysis of the second category: l.1-9, p. 12: the authors should reword this part. I understood that elevation changes of the first period are very different between reference profiles and “managements areas” for ST1, ST3 and HI1. In this way, is it relevant to make a comparison over the second period given that the elevation changes in these two areas are very different over the first period ? Again, which are the criteria to make the difference between the 1st category and the second category ? Very unclear. I make a suggestion (maybe not relevant) to the authors: In order to analyze the results, it could be useful to separate the data in two samples: the first sample would include the same elevation changes in the first period (i.e. on the bisectors of Figures 5 and 6), the second sample would include the other elevation changes. In this way, for the first sample, it would be easier to show that the emergence velocities are very likely similar between the “reference areas” and the “experimental areas”. It would help the Discussion (see my following comments) and would help to convince the reader that the elevation changes of the first sample are mainly due to surface mass balance changes.
7) L. 21-31, p. 12: This part should be rewritten or removed. It seems to come from a technical report with advices to ski resort managers.
8) Discussion about the surface mass balance inferred from elevation changes: it is not convincing. The Discussion about this point is poor. The assumption relative to “In any case, submergence and emergence should be similar for the profiles and the reference profiles” (l. 22, p. 16) is not supported by any data or evidence. In this Discussion, the Equations are not used. I think that the authors should do a thorough analysis (first, please, write Equation of Cuffey and Paterson correctly ). The authors should use this Equation to calculate the uncertainties on mass balance derived from elevation changes, between periods 1 and 2. I think they should only use data with similar elevation changes during the first period (see my previous comment) for such analysis. Please remove the other equations which are not helpful (in addition, Equation named (1) is probably wrong given the density is not the same for the surface mass balance and the entire column and the surface mass balance (deltam). Very confusing. Please remove the equations named (1) and (2) (the authors forgot to name Equation of Cuffey and Paterson). Discussion should be reworded completely.
9) The section “Conclusions” is not well written and should be reworded completely.
10) Table 3: did the authors remove every values for which the ice disappeared between the 1st and the 2nd measurements ?
11) Figure 3: It should be useful to show the “management areas” with dashed line (first panel). a) and b) should improve Figure 3 and caption. The coordinates are not necessary and the authors should add an horizontal scale. In caption, the authors should mention the name of the glacier (Stubai)
12) Figure 4: Provide a), b) and c) for each panel and provide full explanations in the caption about the colors (light blue, dark blue, pink, red)
13) Figures 5 and 6: In the caption, the authors used “median”. Do the authors mean “median “ or “mean” ? Change the vertical axis according my previous comments. Revise the captions according my previous comments
14) Remove Figure 7. Not helpful for the manuscript.
15) I believe that the English of the manuscript should be checked by a native speaker. Many sentences seem to me obscure (although I am not native speaker).
The number of lines correspond to the revised version with track changes
a) Check the ref Abermann et al (p. 2). Year ?
b) Check the brackets for Smiraglia et al (p. 2)
c) L. 20, p. 2: “opened” ? I do not understand
d) L. 2 and 3, p.3: unclear
e) L 6 p 3: unclear
f) L. 18 p 4: confusing
g) L. 16-17, p 6: how did the authors check the accuracy ? It largely depend on the distance to reference station, to the time of acquisition and to number of satellites. The authors should add these information. Where does the standard deviation come from ? Vague
h) Check the numbering of Equations
i) L. 9, p 7: remove this Equation. Unuseful
j) L. 23-26 p 7: very confusing. Explain how you obtained the uncertainties
k) P. 7 : some words are missing, check it. Please Re-read carefully the manuscript.
l) L. 2-3 p 8: reformulate please
m) L.9-15: the text should be revised thoroughly. Finally the authors do not mention the real uncertainty on elevation changes (after interpolation). Very misleading.
n) “Study sites “ section: “high subsidence rates”: not clear. Where does this result come from ? Reference ? Relevant in this section ?
o) L. 29 p 8: this glacier is not mentioned anywhere (except in Figure 1 in very small characters) and the reader is lost…
p) L. 33 p 8: which striking effect ? not relevant in this section
q) P. 9 words are missing.
r) L. 12, p 9: check the verb
s) L. 29 p. 17: per year ?
t) Please Reword Discussion and Conclusions (see my previous general comments)