Identifying the Critical Supply Chains for Black Carbon and CO₂ in the Sichuan Urban Agglomeration of Southwest China

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This study employed a city-level environmental extended MRIO to quantify the BC and CO2 footprints of 21 cities in the SUA from 2012 to 2017, and investigated the impact of industrial chain upgrading on BC and CO2 emissions with SPA. The paper is well written, but there still are some concerns:

 #1 Introduction: The paper focuses on the synergistic study of BC and CO2 emissions at the urban agglomeration level. It is suggested to elaborate further on the paper's innovation and contribution by highlighting the research scale and the specific focus of the study.

 #2 Methodology: It is advisable to create a flowchart to provide a clear visual representation of the research framework employed in the paper.

 #3 It is recommended to include a map of the Chengdu urban agglomeration to depict its geographical location and constituent cities.

 #4 Results: The paper mentions that Sichuan is a primary provider of west-to-east power transmission, imposing a significant environmental burden to support the more developed eastern regions. It would be beneficial to investigate the pattern of BC and CO2 trade and transfer between the Sichuan urban agglomeration and other regions in the country, similar to the approach followed in "Sustainable Cities and Society, 2022, 83: 103977."

 #5 In Figure 1 and related context, the term "driving factors" should be expressed as "final demand categories" to avoid confusion with the driving factors identified in the structural decomposition analysis (SDA).

 #6 Discussion: The discussion section appears to repeat certain aspects of the results section. In the discussion, it is important to provide an interpretation of the factors contributing to the results and make comparisons with findings from other relevant studies.

 #7 Policy implications: The policy recommendations are quite general. The paper's primary contribution lies in the research on trade-induced BC and CO2 transfers in the Chengdu urban agglomeration. It is essential for the authors to propose specific and targeted policy recommendations based on the research results, particularly regarding key regions and industries for BC and CO2 co-control.

Comments on the Quality of English Language

Extensive editing of English language required

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Authors,the chosen multivariate model

suits perfectly the purpose of your research.The general model suggests a geometrical convergence on the outputs.

If it might be an invitation,a future extension of this work on partial correlations between the chosen variables can eventually be thought.

Thinking about to whom your work can be addressed,I would recommend wherever possible,the choice of alternatives systems of transport in the supply chain,like railways or river navigation.

Author Response

Dear reviewer,

Thank you very much for your review and valuable feedback on our research. We greatly appreciate your recognition of the multivariate model we employed and its geometric convergence on the outputs.

We wholeheartedly agree with your recommendation to consider alternative transportation systems, such as railways or river navigation, in the supply chain. This approach can effectively reduce carbon emissions and minimize environmental impacts, promoting more sustainable transportation methods.

We will carefully consider your suggestions and incorporate them into our future research endeavors. Once again, we would like to express our gratitude for your valuable advice and support.

Sincerely,

Xiaoling Zhang

Reviewer 3 Report

Comments and Suggestions for Authors

Comments for author File: Comments.pdf

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

Black Carbon (BC) and CO2 are the principal chemical aerosol components generated during combustion, both of which play a key role in air pollution, human health and climate change. Several studies of CO2 and BC have been conducted all over the world to assess their emission sources. The present study was carried out in Sichuan Urban Agglomeration (SUA) located in Southwest China. The objective consisted of quantifying the heterogeneous impacts and emission supply chains of BC and CO2 emissions from economic and industrial activities in the SUA. In this context, the authors have used the environmental extended input-output (EE-MRIO) model to inspect the BC and CO2 footprints of 21 cities in SUA. The used methods were adequately described in the Methods section and the obtained results were illustrated in Figures and discussed in Section 4.

I recommend the publication of the present paper after minor revision.

Comments for author File: Comments.pdf

Author Response

Dear Reviewer,

Thank you for reviewing our manuscript and providing valuable feedback on the grammar errors. We appreciate your attention to detail in improving the language quality of our paper.

Regarding the concern about the clarity of the images, we apologize for any inconvenience caused. We will take immediate action to enhance the resolution of the images in the revised version. We assure you that the subsequent submission will include clearer and more legible figures.

If you have any further suggestions or comments on the revised manuscript, we would be grateful to receive them. Your expertise and insights are highly valued in refining our research.

Thank you again for your time and valuable input. We look forward to your continued guidance and collaboration.

Best regards, 

Xiaoling Zhang 

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The atuors have answered my concerns and I recommend it for publication in Sustainability.

Comments on the Quality of English Language

Minor editing of English language required

Reviewer 3 Report

Comments and Suggestions for Authors

I agree with the revisions for the manuscript done by the authors. No more comments, the author has incorporated good changes in the manuscript.