Source Apportionment of Ambient Aerosols during a Winter Pollution Episode in Yinchuan by Using Single-Particle Mass Spectrometry

Round 1

Reviewer 1 Report

AS far as I know that SPAMS instrument has been used for many cities in China for source appointment of ambient aerosols with many relative published papers. This manuscript is a routine one for source appointment of PM2.5 in Yinchuan, a city in Northwest China. The results are also similar to other cities with the aerosol pollution mainly from traffic emissions, industrial emissions, and secondary inorganic conversion. However, it is well written and provide new data for about the ambient aerosols for Northwest China, which will enlarge the knowledge of the characteristics of PM2.5 in China. I suggest to accept after mino revision.

1. Yinchuan is a city in Northwest China. The climate is very special in China which can cause the different characteristics for pollution. Thus, the characteristics of the  climate and the topography of Yinchuan should be clearly provided. 

2. The comparation can be done between Yinchuan and other cities, such as shanghai and Beijing. You may find some special findings of the PM2.5 in Yinchuan.

3. The manuscript presents enough monitoring data and results. However, more discussion and intrinsic reasons should be provided in great detail.

Author Response

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Author Response File: Author Response.docx

Reviewer 2 Report

In this study, Li et al. characterized the ambient particle using an SPAMS.  It is an interesting study. However, some key information like the source apportionment method and mass spectral profiles for the factors are missing before evaluating the soundness of the conclusion.  It can be published after addressing the following comments.

Line 40. “University of California has the most representative research team worldwide studying atmospheric particles by using single-particle technology” this sentence comes out of nowhere. Maybe add some citations to support their representative studies?

Line 62. “the annual average PM2.5 concentration has been generally declining, but the regional PM2.5 pollution is exacerbated in winter, which cannot be ignored” Any data to support the claim? Or literature?

Line 87. What is the response factor obtained for the mass calibration? Also provide the mass and time resolution for SPAMS.

Line 97. How close is the air quality data in km? What are the diurnal cycles of PM2.5 like? Given the statement of 88-90, I expect a well defined rush hours peaks for PM2.5, CO, and NO2.

Line 115. Only 58% is analyzed. Why not all particle mass were analyzed?

Line 117. You may need to specify the ART-2a method in the Method section. Only with more details available, can we judge the robustness of this method.

What is the advantage of ART-2a over k-means? As far as I know, K-means is widely used for aerosol-type separation.

Line 124. What is the diurnal cycle for all the factors? Diurnal patterns can help justify the identification of factors including traffic emission? What is the correlation coefficient between the factors and external measurements of e.g., NO2, SO2, CO?

Line 129. The PM2.5 values are daily means or hourly means?

Figure 4. Only the time series of the factors is provided. What are the  mass spectral profiles for all the factors?

 

 

 In this study, Li et al. characterized the ambient particle using an SPAMS.  It is an interesting study. However, some key information like the source apportionment method and mass spectral profiles for the factors are missing before evaluating the soundness of the conclusion.  It can be published after addressing the following comments.

 

Line 40. “University of California has the most representative research team worldwide studying atmospheric particles by using single-particle technology” this sentence comes out of nowhere. Maybe add some citations to support their representative studies?

Line 62. “the annual average PM2.5 concentration has been generally declining, but the regional PM2.5 pollution is exacerbated in winter, which cannot be ignored” Any data to support the claim? Or literature?

Line 87. What is the response factor obtained for the mass calibration? Also provide the mass and time resolution for SPAMS.

Line 97. How close is the air quality data in km? What are the diurnal cycles of PM2.5 like? Given the statement of 88-90, I expect a well defined rush hours peaks for PM2.5, CO, and NO2.

Line 115. Only 58% is analyzed. Why not all particle mass were analyzed?

Line 117. You may need to specify the ART-2a method in the Method section. Only with more details available, can we judge the robustness of this method.

What is the advantage of ART-2a over k-means? As far as I know, K-means is widely used for aerosol-type separation.

Line 124. What is the diurnal cycle for all the factors? Diurnal patterns can help justify the identification of factors including traffic emission? What is the correlation coefficient between the factors and external measurements of e.g., NO2, SO2, CO?

Line 129. The PM2.5 values are daily means or hourly means?

Figure 4. Only the time series of the factors is provided. What are the  mass spectral profiles for all the factors?

 

 

Author Response

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Author Response File: Author Response.docx

Reviewer 3 Report

Comments for author File: Comments.pdf

Author Response

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Author Response File: Author Response.docx