Thank you very much for the comments and suggestions. All our authors have discussed the review comments and will carefully revise each item based on the opinions.

Reply to the following comments one by one.

• The research question is not clear. In Introduction, authors invested quite some effort in showing the importance of supra-permafrost groundwater (SG), but much less in reviewing the status quo of SG dynamics and proposing specific scientific research questions. Such issues make the reader very confusing at the first glance of this paper. For instance, in lines 58-67, the authors listed the influencing factors of SG variation, but without presenting how these factors impact SG variations and what questions need to be solved. One sentence of “However, there is a shortfall in systematically revealing the linkage between the seasonal hydrothermal change of AL, SG, and surface runoff.” is far from enough.

Reply: we agree with the reviewer, and will carefully revise the “Introduction”.

• The structure of the manuscript needs a major overhaul as it is difficult to find a red line for each section or paragraph. For example, why is the Sigmoid–Boltzmann formula in Result? It should be in Methods and materials 2.4, and why this formula is used for analysis? What is the physical foundation behind? A polynomial cubic formula is used in line 205 while a sigmoid formula is used in line 186. What is the difference between these formulae; what is the key point in “3 Seasonal characteristics of SG”? Can you use one brief sentence at the beginning of each paragraph to give some general findings or ideas? Meanwhile, I may suggest change the old 3 into “Seasonal characteristics of SGL, ST, and SVMC”, and move related descriptions from 4 to 3. What’s more, the current Discussion is not a not real “discussion”, the authors showed the importance of SG again, but without presenting what’s new in this study compared with previous studies. Moreover, I do think the “framework” should be in “discussion” with a focus on what general or/and new patterns you have found, what processes are involved, and corresponding implications for future studies.

Reply: We agree with the opinion and suggestion in “Discussion” section. We will rewrite the “Discussion” considering the reviewer’s comments. In addition, the section 3 will be revised to “Seasonal characteristics of SGL, ST, and SVMC”. The detailed instruction in section 3 and 4 will be revised correspondingly. The formulas selected in the text are based on the results of comparative analysis according to existing reference (Wang et al., 2012). We will move the formulas and instructions in section 4 to section 2.4, so as to make the structure more reasonable.

• More details are needed in Methods and materials to make sure the reliability of all results in this study. For example, (i) how to define the four different periods of SGL? What do you mean “tip points”? How to select the tip points in a scientific way? (ii) more detailed calibration procedures for SGL, SVMC, and ST sensors are also needed; (iii) how are the geographical distribution of observations for SGL, SVMC, and ST, meteorological variables and river level? SGL, ST, SVMC data were at point-scale, while the river level reflected the overall discharge at the catchment scale. How do authors consider scaling issues throughout the analysis? (iii) what is the hydrogeological condition in the study area? Is SG recharged by river or river is recharged by SG? Authors need to make it very clear. Otherwise, most readers will not be able to assess the results as well as the reasoning behind the interpretation.

Reply: thanks for the detailed comments and suggestions. After serious discussions, all our authors agreed with the reviewer’s opinion and will carefully revise the Methods and materials.

• Four different stations with climatic gradients are selected in this study, a comparative analysis is thus expected for readers. However, almost nothing related is shown in this paper.

Reply: thanks for the comment. The analysis in four different stations selected in this study was aim to shown common characteristics of the linkage between SG, ST, SVMC, and RL in alpine permafrost watersheds. So, the manuscript has weakened the difference.  

• More in-depth analyses are needed to illustrate the impact of ST and SVMC changes on SGL variations, the role of SG in regulating river runoff, and how SGL responses to rainfall events. Currently, most analyses are simple descriptions about the statistical relationship between variables.

Reply: thanks, we will carefully revise the manuscript according to the reviewer’s comments and suggestions.

• Pay attention to the consistency problems in this paper. For example, in lines 95-96, it says “the analysis was conducted in a hydrological year (from October 1 to September 30)”, while the time series in Figure 3 are contrasted with this, and also different with each other for each small figure. Meanwhile, such time series in Figure 3 are also different to those in Figure 2, making it hard for readers to follow expressions in line 132.

Reply: thanks and we will revise the figures and text throughout the manuscript.

• The level of English does not yet meet the standard required for scientific publications and requires a detailed round of proof reading by a native English speaker with hydrology background.

 Reply: thanks. The English of the manuscript has revised by expert English editors by “Editage”. To enhance the English, we will ask other English editor with hydrology background check and revise the proof again.

Specific points:

L.12: what is runoff concentration here?

 Reply: the original meaning of the words in the sentence was to refer the runoff confluence. We will revise it.

L.38: change into “it plays a crucial role in regulating land surface processes…”

 Reply: ok, we will revise it.

L.39: what do you mean “the SG maintains a high value”, I suppose it should be the SGL?

 Reply: Thanks and we will replace SG by SGL.

A separated table with site-specific characteristics including location, altitude, vegetation type, annual mean precipitation, air temperature, soil properties, and so on, could better illustrate the gradient.

 Reply: We will seriously consider the suggestion.

L.101: The writing should be more concise. Such expressions like “nearby national weather stations” without the distance are not reliable.

 Reply: Thanks for the suggestion and we will check and revise the similar expressions.

L.121-122: Refs are needed here for the method and algorithm.

 Reply: ok, we will revise it.

L.126: change into the seasonal variation of SGL…

 Reply: ok, we will revise it.

L.163-164: refs are needed to support your inferences.

 Reply: ok, we will revise it.

L.233: use correlation analysis results to prove this.

 Reply: ok, we will revise it.

L.299-300: refs are needed again.

 Reply: ok, we will revise it.

L.317: only variables of ST and SVMC are considered for evaluating their effect on SGL changes, how could you get the conclusion that they are the primary impact factors.

 Reply: it is mainly because of the large correlation coefficient. We will check the expression and revise the corresponding sentences to make them more accurate.

1. The English of the manuscript is good, while there are a few sentences which are too long and a bit complex. It is suggested to be separated in a few short sentences. For example, the sentence in line 214-217 “Although the SVMC and ST both have good relationships with the SGL below a depth of 70 cm, the variation scope of the SVMC is minimal, and the freezing process of deep soil determines the uplift process of the AL lower boundary, which affects the SGL. Therefore, the deep layer also more directly impacts the SGL owing to the ST.”

Reply: We all authors agree with the opinion. We will revise the sentences and do a detailed round of proof reading by a native English speaker with hydrology background.

2.The font of text and label in some Figures, such as the Figure 1 and Figure 4, are too small and not very clear. The color of the lines in the subtable of Figure 5b is inconsistent.

Reply: Thank for the opinion and we will accordingly revise the figures.

3. The section “Discussion”. In the section, I recommend to add some discussions about the different impacts of vegetation and the slope on SGL dynamics, although they maybe not affect the conclusion of the study.

Reply: it is a good suggestion. We will consider the impacts of vegetation and slope on the SGL changes, and revise the “Discussion” section accordingly.

4. Line 337, one more space in “The change----”.

Reply: thanks, we will revise it.

5. Line 58 and Line 62, the SG should be SGL?

Reply: that is right, and we will revise it.

6. In line 96, the “---in a hydrological year”. Does it refer a specific year or the annual average value?

Reply: it refers to a specific hydrological year because of the data limitation. We will add detailed information in the section “Experimental data”.

7. Why the data of station HLG was not shown in Figure 3? No data or other reasons? It should be introduced in the text.

Reply: The data of ST anf SVMC in the HLG station is missing. We will check the data again or use interpolation of data in nearby stations to supplement the missing data. The corresponding instruction will be added in the text.