Spatial-Temporal Variation of Snow Black Carbon Concentration in Snow Cover in Northeast China from 2001 to 2016 Based on Remote Sensing

Round 1

Reviewer 1 Report

This study uses remote sensing technology to study the solubility of black carbon, and then to determine the impact of human activities on snow pollution. Although it has a certain use value, the theoretical contribution is not enough. At the same time, the article is not highly logical in the analysis of influencing factors, and there is no scientific analysis basis and theoretical support.

1. Please modify the references appropriately, delete some relatively irrelevant references, and it is best not to quote more than two references in a sentence.
2. The analysis of influencing factors is done poorly. Failed to analyze the specific influencing factors and why these factors were selected. There is no powerful analysis of the degree of mutual influence between them.
3. The conclusion of the article needs further revision. It is necessary to summarize the main contributions of the article and the future application prospects of the article, and emphasize some of the shortcomings of the article.

4.The research framework needs to be supplemented to further clarify the overall thoughts and ideas of the article.

5.The author should increase the discussion part.The discussion part should emphasize the advantages and innovations of the evaluation framework. It is more necessary to highlight the new and different understandings of the past.

Author Response

please see the attachment. thank you.

Author Response File: Author Response.pdf

Reviewer 2 Report

This article simulated the BC concentration on the surface snow of northeast China using an asymptotic radiative transfer model, To obtain long-term and stable regional BC simulation data. The content of the whole article is integrated. But I have the following suggestions and questions about the article:

1. Your article is to analyzes the temporal and spatial distribution of black carbon based on remote sensing. It is suggested to be embodied in the title.
2. Your article does not seem to fully describe the latest knowledge related to the research problem. For example, why did you choose to combine the ART model and MODIS data? It is suggested to clearly define their advantages in the introduction.
3. You mentioned that black carbon will reduce the surface albedo of snow, to increase its absorption of solar radiation and make snowmelt. Can there be data and charts to illustrate the change of snow thickness from 2001 to 2016?
4. Figure 4 shows the change of average BC concentration in the snow in Northeast China from 2001 to 2016, but it can be seen that the overall change is small while the emission increases in terms of energy consumption. Can you explain the reason in the discussion?
5. Could you add the comparison of energy structure and consumption between urban and rural areas? Is there a significant relationship between the urbanization difference and the black carbon concentration in the snow cover?
6. What are the projection settings in all maps? As shown in Figure 1, the directions of the North compass and the longitude and latitude network are inconsistent, and this deviation could have a great impact on high latitude areas.
7. The formats of the figures are not uniform in the contents. For example, Figures 1, 4, 8, and 12, ‘.’ are missing, and whether ‘:’ is required after (a), (b), and (c)?

Author Response

Please see the attachment

Author Response File: Author Response.docx

Reviewer 3 Report

The spatial and temporal BC concentration in Northeast China are studied in this research and interesting recommendations are proposed. Please consider the following feedbacks:

• Fig. and Figure are both used in text
• Please improve the quality of figures
• line 351: reference to a wrong figure
• please change the color spectrum to red/blue in some images. The Red and green combination is a very common color blindness.
• please carefully review the paper as there are misspellings, styling inconsistensies, punctuations error, and wrong use of references. 

Author Response

Please see the attachment

Author Response File: Author Response.docx