Analysis of the Spatial and Temporal Evolution of Energy-Related CO₂ Emissions in China’s Coastal Areas and the Drivers of Industrial Enterprises above Designated Size—The Case of 82 Cities

Round 1

Reviewer 1 Report

The paper is complete in its lines, more substantial in content, and written logically and clearly. However, the following problems still exist:

1. In the part of "Literature Review", there is less literature about the key cities in the coastal region mentioned below, and it is suggested that the authors should make additional explanations in order to ensure the consistency of the lines.

2. In the analysis of "spatial and temporal evolution of CO2 emissions", too much emphasis is placed on the north, central, and south regions, and it is suggested that the more prominent and typical cities should be analyzed.

3. In the "Conclusion" section, the conclusion is similar to the analysis of the results, and it is suggested to streamline the views in the conclusion section and highlight the key points in the conclusion section of the paper.

4. The authors need to be more specific in presenting the contribution of this study.

English can be improved a bit.

Author Response

Response

Dear reviewer, thank you very much for your suggestion. We seriously consider your comments, which contribute greatly to this study.

1. Based on your suggestions, we have added the existing relevant literature on several key cities in the coastal region of China in the paper in the introduction section, and we have drawn on the findings of this literature to support this study.

The complete revisions can be found in the introduction and References of the revised draft (Page 2 of Introduction, line 79 “Penultimate line of the second paragraph”, References 10-13).

It is accompanied by the following references:

1. Liang, Q. D.; Feng, X. Z.; Du, X. L. Research on the influencing factors of carbon emission from energy consumption based on LMDI-Taking Tangshan City as an example[J]. Environment and Sustainable Development, 2020, 45(01):150-154.
2. Du, Z. W.; Lv, L.C. Carbon emissions and urban development in Guangzhou [J]. SAR Economy, 2012(09):51-53.
3. Ye, B.; Liang, X. Y.; Song, Y. Z. Study on industrial carbon emission reduction pathway in Shenzhen under the goal of "carbon neutrality"[J]. SAR Economy, 2022(10):17-24.

 

2. Dear reviewer, Thank you very much for your suggestion. According to your suggestion, we have added a comparison of regions in the "Characterization of the temporal evolution of CO₂ emissions" section, as well as a detailed description of the characteristics and reasons for the formation of typical cities in China's coastal regions. Thank you again for your suggestion.

The complete modifications are in the "3.1 Characterization of the temporal evolution of CO₂ emissions" section of the revised manuscript. Second paragraph（Pages 7-8）.

3. Dear Reviewers, Thank you very much for your suggestion. According to the unanimous suggestion of you and several other reviewers, we have added a new "Discussion" section, and put the interpretation and analysis of the results of the study into the "Discussion" section, streamlined the ideas in the "Conclusion" section, and highlighted the research focus of this paper. Thank you again for your suggestions.

The complete modifications are in the Discussion and Conclusion sections (Pages 14-17) of the revised manuscript.

 

4. Dear Reviewers, Thank you very much for your suggestion. Based on your valuable suggestions, we have presented the contributions of this study specifically in the Discussion section so that readers can more clearly understand the focus of this paper. Thank you again for your suggestions.

The complete modifications are in the Discussion (First paragraph, Pages 14-15) of the revised manuscript.

 

Dear reviewer, special thanks to you for your good comments. The other changes are mainly about the grammars and spellings, so we didn’t mark them. We tried our best to improve the manuscript and made some changes in the manuscript according to your and other reviewers’ suggestions. These changes will not influence the content and framework of the paper. We appreciate for Reviewers’ warm work earnestly, and hope that the correction will meet with approval. Once again, thank you very much for your comments and suggestions.

 

Author Response File: Author Response.docx

Reviewer 2 Report

This paper analyzes the spatial and temporal evolution of energy-related CO2 emissions in China's coastal areas and the drivers of main industrial enterprises within 82 cities. The conclusion can provide some guidance for the realization of the "double carbon" target in China. The paper should be revised considering the following comments.

 

1. In the Introduction, the authors should clearly explain the reason for the selection of coastal cities, and the indexes of the influencing factors. Moreover, why spatial and temporal evolutions of coastal areas are needed to analyze?

2. In Section 3, the highest emissions of the city of Tangshan, Shanghai and Nanjing, etc., Please provide a more in-depth discussion of the reason of highest emissions in these cities.

3. In Section 3, regarding the growth in the number of cities with ultra-high carbon emissions, please explore the reasons, and describe the trends, and analyze their impact on the environment.

4. For the central coastal regions of North Jiangsu and South Zhejiang and the southern coastal region of North Guangdong, specific explanations should be provided about the highest number of low carbon emission cities.

5. In Section 4, the conclusion is too long. In addition, the limitation and future research should be proposed.

 

6. Please carefully check the unit of CO2 emission factors in Table 1. For example, the units of heat and electricity emission factors are not 10kt/10kt.

Author Response

Dear reviewer,

Thank you very much for your comments and professional advice. These opinions help to improve academic rigor of our article. Based on your suggestion and request, we have made corrected modifications on the revised manuscript. Furthermore, we would like to show the details as follow：

This paper analyzes the spatial and temporal evolution of energy-related CO₂ emissions in China's coastal areas and the drivers of main industrial enterprises within 82 cities. The conclusion can provide some guidance for the realization of the "double carbon" target in China. The paper should be revised considering the following comments.

1. In the Introduction, the authors should clearly explain the reason for the selection of coastal cities, and the indexes of the influencing factors. Moreover, why spatial and temporal evolution of coastal areas is needed to analyze?
2. In Section 3, the highest emissions of the city of Tangshan, Shanghai and Nanjing, etc., please provide a more in-depth discussion of the reason of highest emissions in these cities.
3. In Section 3, regarding the growth in the number of cities with ultra-high carbon emissions, please explore the reasons, and describe the trends, and analyze their impact on the environment.
4. For the central coastal regions of North Jiangsu and South Zhejiang and the southern coastal region of North Guangdong, specific explanations should be provided about the highest number of low carbon emission cities.
5. In Section 4, the conclusion is too long. In addition, the limitation and future research should be proposed.
6. Please carefully check the unit of CO₂ emission factors in Table 1. For example, the units of heat and electricity emission factors are not 10kt / 10kt.

 

Response

1. Dear reviewer, thank you very much for your suggestion. According to your suggestion, in the introduction, we have added the reasons for choosing the coastal cities in China in the background and significance of the study in the first paragraph, and in the third paragraph, we have added the reasons for choosing the indicators of influencing factors and analyzing the spatial and temporal evolution of the coastal areas. Thank you again for your suggestions.

The complete modifications are in the Introduction (Page 2, lines 46-50, Page 3, lines 106-116, Page 3, lines 141-148) of the revised manuscript.

 

2. Dear reviewer, thank you very much for your suggestion. According to your suggestion, we have added the reasons for the highest emissions in Tangshan, Shanghai and Nanjing in the "3.1 Characterization of the temporal evolution of CO₂ emissions" section, and analyzed them in depth according to relevant references and local conditions. Thank you again for your suggestions.

The complete modifications are in the Results and Analysis (Pages 7-8, lines 308-314) of the revised manuscript.

 

3. Dear reviewer, thank you very much for your suggestion. According to your suggestion, we have added the reasons for the increase in the number of cities with super-high CO₂ emissions and analyzed their impacts on the local environment in the section "Results and Analysis". Thank you again for your suggestions.

The complete modifications are in in the Results and Analysis (Page 8, lines 319-323) of the revised manuscript.

 

4. Dear reviewers, thank you very much for your suggestions. Based on your suggestion, we have added detailed information on the reasons why the number of cities with low carbon emissions is the highest in the coastal area of northern Jiangsu, the central coastal area of southern Zhejiang, and the southern coastal area of northern Guangdong. Thank you again for your suggestions.

The complete modifications are in the Results and Analysis (Page 8, lines 302-308) of the revised manuscript.

 

5. Dear reviewer, thank you very much for your suggestion. Based on your and other reviewers' unanimous suggestions, we have streamlined the four arguments in the "Conclusion" section, and added a new "Discussion" section, in which the limitations and future research directions of this study are shown. Thank you again for your suggestions.

The complete modifications are in the Discussion (Page 16, lines 618-625) and Conclusion (Pages 16-17) of the revised manuscript.

 

6. Dear reviewer, thank you very much for your suggestion. Based on your valuable suggestions, we have carefully examined the units of CO₂ emission factors in Table 1. As for your question that the unit of the emission factor of heat and electricity is not 10kt/10kt, we compared the unit in the original data table again. Since the data of various energy sources in our original data table are converted according to the conversion coefficient of standard coal, in order to ensure the consistency of the unit, we standardized the unit of CO₂ emission factor of each energy source to 10kt. Thank you again for your suggestions.

The complete modifications are in the Research Methodology (Page 5, line 210, Table 1) of the revised manuscript.

 

Dear reviewer, special thanks to you for your good comments. The other changes are mainly about the grammars and spellings, so we didn’t mark them. We tried our best to improve the manuscript and made some changes in the manuscript according to your and other reviewers’ suggestions. These changes will not influence the content and framework of the paper. We appreciate for Reviewers’ warm work earnestly, and hope that the correction will meet with approval. Once again, thank you very much for your comments and suggestions.

Author Response File: Author Response.docx

Reviewer 3 Report

1. There are still some minor errors in the text. For example. Some literature has incorrect formatting.

2. Figures 1 and 2 are not clear. Where did the data in Table 1 come from?

3. LMDI method to decompose the driving factors affecting the CO2 emissions of industrial enterprises above designated size in China's coastal region into five factors, which should be give more details.

4. Urban CO2 emission intensity Moran's I. index and Z-value in China's coastal region (2005-2020), why no near two years?

5. Among them, energy-related CO2 emissions from coastal areas are characterized by northern coastal areas > central coastal areas > southern coastal areas. This is a matter of common sense and not an important conclusion.

Energy-related CO2 emissions in a small number of cities in the coastal region of China, especially Guangzhou and Shenzhen, are showing a slow decline after a steady increase to the peak, why?

Author Response

Dear reviewer,

Thank you very much for your comments and professional advice. These opinions help to improve academic rigor of our article. Based on your suggestion and request, we have made corrected modifications on the revised manuscript. Furthermore, we would like to show the details as follow：

1. There are still some minor errors in the text. For example. Some literature has incorrect formatting.
2. Figures 1 and 2 are not clear. Where did the data in Table 1 come from?
3. LMDI method to decompose the driving factors affecting the CO₂ emissions of industrial enterprises above designated size in China's coastal region into five factors, which should be give more details.
4. Urban CO₂ emission intensity Moran's I. index and Z-value in China's coastal region (2005-2020), why no near two years?
5. Among them, energy-related CO₂ emissions from coastal areas are characterized by northern coastal areas > central coastal areas > southern coastal areas. This is a matter of common sense and not an important conclusion.

Energy-related CO₂ emissions in a small number of cities in the coastal region of China, especially Guangzhou and Shenzhen, are showing a slow decline after a steady increase to the peak, why?

 

Response

1. Dear reviewer, Thank you for your careful review. As a result of your reminder, we have carefully checked the text for errors in the formatting of literature citations. Thank you again for your suggestions.

The complete modifications are in the Introduction and References (Pages 1-3, Paragraphs 1-4) of the revised manuscript.

 

2. Dear reviewer, thank you very much for your suggestion. According to your suggestion, we have adjusted the clarity of Figures 1 and 2 to see if they meet the criteria. In addition, we have explained the sources of the standard coal conversion factors and CO₂ emission factors in the lower text of Table 1. Thank you again for your suggestions.

The complete modifications are in the Methods, Results and Analysis (Page 5, lines 203-208, Page 9 and page 11) of the revised manuscript.

 

3. Dear reviewer, thank you very much for your suggestion. According to your suggestion, in the third paragraph of the introduction, we add the reasons for the five driver indicators in the LMDI methodology. Thank you again for your suggestions.

The complete modifications are in the Introduction last paragraph (Page 3, lines 141-148) of the revised manuscript.

 

4. Dear reviewer, thank you very much for your suggestion. In response to your question "Why is there no data for the last two years for the Moran's I. and Z-value of CO₂ emission intensity of Chinese coastal cities (2005-2020)? ", we would like to thank you for pointing out that we do not have the data for the last two years. We would like to explain this question to you again. As the data of this study are based on the data of each city's statistical department, which requires high data uniformity and accuracy, and the data of some cities have not been updated to the latest two years, the study period of 2005-2020 has been selected for this study. Thank you again for your suggestions.

The complete modifications are in the Data sources (Page 4, lines 170-173) of the revised manuscript.

 

5. Dear reviewer, Thank you very much for pointing out our error in this regard. We have deleted the sentence "Energy-related CO₂ emissions in coastal areas are characterized by: North Coastal Area > Central Coastal Area > South Coastal Area" in the conclusion section. In addition, in response to your question "Why do energy-related CO₂ emissions in a few cities in China's coastal regions, especially Guangzhou and Shenzhen, show a slow decline after a sustained increase to the peak?", we have deleted this sentence from our conclusions. We have refined the question in the corresponding section of the paper. Thank you again for your suggestions.

The complete modifications are in the Conclusion (Page 16, lines 635-637) and Discussion (Page 15, lines 552-567) of the revised manuscript.

 

Dear reviewer, special thanks to you for your good comments. The other changes are mainly about the grammars and spellings, so we didn’t mark them. We tried our best to improve the manuscript and made some changes in the manuscript according to your and other reviewers’ suggestions. These changes will not influence the content and framework of the paper. We appreciate for Reviewers’ warm work earnestly, and hope that the correction will meet with approval. Once again, thank you very much for your comments and suggestions.

Author Response File: Author Response.docx

Reviewer 4 Report

1. Line 139-145 should be deleted.

2. The legend of Figure 1 is not clear, and important cities should be labeled in text in the figure.

3. In Figure 2, legend is “Legend”, not “Figure Legend”, and important cities should be labeled in text.

4. Part “4 Conclusions” should be simplified by highlighting the 3-4 key findings of the study; at the same time, a section should be added before the “Conclusions” to discuss the findings of the study and the corresponding countermeasures proposed.

5. English grammar needs to be rechecked, there are a lot of errors, such as “3.1 Temporal energy-related CO2 emissions Characteristics”?

6. The LDMI method is a relatively old method to study carbon emission drivers, and what advantages exist with DEA, STIRPAT model, GTWR model, etc., and why the LDMI method was chosen for this study need to be elaborated in Introduction.

7. Carbon emission drivers generally also take into account environmental regulations and the level of industrial agglomeration, so why are these two factors not addressed in this study?

Extensive editing of English language required.

Author Response

Dear reviewer,

Thank you very much for your comments and professional advice. These opinions help to improve academic rigor of our article. Based on your suggestion and request, we have made corrected modifications on the revised manuscript. Furthermore, we would like to show the details as follow：

1. Line 139-145 should be deleted.
2. The legend of Figure 1 is not clear, and important cities should be labeled in text in the figure.
3. In Figure 2, legend is “Legend”, not “Figure Legend”, and important cities should be labeled in text.
4. Part “4 Conclusions” should be simplified by highlighting the 3-4 key findings of the study; at the same time, a section should be added before the “Conclusions” to discuss the findings of the study and the corresponding countermeasures proposed.
5. English grammar needs to be rechecked, there are a lot of errors, such as “3.1 Temporal energy-related CO₂ emissions Characteristics”?
6. The LDMI method is a relatively old method to study carbon emission drivers, and what advantages exist with DEA, STIRPAT model, GTWR model, etc., and why the LDMI method was chosen for this study need to be elaborated in Introduction.
7. Carbon emission drivers generally also take into account environmental regulations and the level of industrial agglomeration, so why are these two factors not addressed in this study?
8. Comments on the Quality of English Language Extensive editing of English language required.

 

Response

1. Dear reviewer, thank you very much for your suggestion. According to your suggestion, we have deleted the part of "lines 139-145". Thank you again for your suggestions.

The complete modifications are in the Introduction last paragraph (Page 4) of the revised manuscript.

 

2. Dear reviewer, thank you very much for your suggestion. According to your suggestion, we have modified the font size of the legend of Fig. 1, and labeled the capital cities and planned cities of each province in the figure with text, and labeled the city of Tangshan. Thank you again for your suggestions.

The complete modifications are in the Results and Analysis (Page 9, Figure 1) of the revised manuscript.

 

3. Dear reviewer, we apologize for the error caused by our carelessness, and thank you for your reminder. We have changed the legend in Figure 2 from "Figure Legend" to "Legend". Thank you again for your suggestions.

The complete modifications are in the Results and Analysis (Page 11, Figure 2) of the revised manuscript.

 

4. Dear reviewer, thank you very much for your suggestion. According to the unanimous suggestion of you and several other reviewers, we have simplified the "Conclusion", emphasized the key points of the study, and highlighted the four main findings of the study; at the same time, at your suggestion, we have added a "Discussion" section before the "Conclusion", which explains in detail the research contribution, analysis of findings and limitations of this paper. Thank you again for your suggestions.

The complete modifications are in the Discussion (Pages 14-16) and Conclusion (Page 16, Pages 635-651) of the revised manuscript.

 

5. Dear reviewer, thanks to your careful scrutiny, we have made our best efforts to embellish and revise the English grammar in the manuscript. In addition, we uploaded the manuscript to the official MDPI touch-up platform, and invited professional English editors to touch up the whole manuscript. The touch-up report has been issued. Thank you again for your suggestions.

 

6. Dear reviewer, thank you very much for your suggestion. Based on your suggestion, we have added the reasons for choosing the LDMI method in the introduction section. Thank you again for your suggestions.

The complete modifications are in the Introduction (Page 3, lines 141-148) of the revised manuscript.

 

7. Dear reviewer, we would like to thank you for your professional comments on the selection of our driver indicators, and we would like to provide you with an explanation for your comment "Carbon emission drivers generally also take into account environmental regulations and industrial agglomeration levels". At the beginning of the selection of driver indicators, we have also consider environmental regulations and industrial agglomeration level, but due to the actual data collection process, we found that the data of these indicators are less, and to ensure the constant equation requirements of the LDMI model, so this paper did not choose these two indicators. In the future, we will pay more attention to the consideration of this kind of factors. Thank you again for your suggestions.

 

8. Dear reviewer, thank you very much for your suggestion. According to the suggestions of you and other reviewers, we submitted the paper to the official MDPI touch-up platform for touching up, where we did not list the changes, but we have marked them all in the revised paper, and we hope that the revised English language expression will be recognized by you.

 

Dear reviewer, special thanks to you for your good comments. The other changes are mainly about the grammars and spellings, so we didn’t mark them. We tried our best to improve the manuscript and made some changes in the manuscript according to your and other reviewers’ suggestions. These changes will not influence the content and framework of the paper. We appreciate for Reviewers’ warm work earnestly, and hope that the correction will meet with approval. Once again, thank you very much for your comments and suggestions.

Author Response File: Author Response.docx

Reviewer 5 Report

What is the main question addressed by the research?

This paper analyzes the evolution patterns and drivers of CO2 emissions due to energy consumption of industrial enterprises above designated size in 82 cities in China's coastal regions from 2005 to 2020.

Although the document maintains an order in its structure, written logically and clearly, there are still some minor errors in the format of the text:

In the "Literature Review" section there is little information on the key cities of the coastal region, it is suggested that the authors carry out additional functions to guarantee the importance of the information that they want to disclose.

Authors should clearly explain the reason for the selection of coastal cities and the indices of the influencing factors.

In the analysis of the "spatial and temporal evolution of CO2 emissions", too much emphasis is placed on the northern, central and southern regions, and it is suggested to analyze the most important or traditional cities to specify the information.

Do you consider the topic original or relevant in the field? Does it address a specific gap in the field?

China's carbon emissions account for about a quarter of the world's total greenhouse gas emissions. Considering the serious situation of global warming, it is necessary to reveal the spatial and temporal differences and analyze the indirect effects of carbon emissions between regions.

The growth in the number of cities with high carbon emissions is one of the most important reasons for describing trends and analyzing their impact on the environment.

Authors should clearly explain the reason for the selection of coastal cities and the indices of the influencing factors. What is the reason to analyze the spatial and temporal evolutions of the coastal areas?

What does it add to the subject area compared with other published material?

This paper analyzes the spatial and temporal evolution patterns and drivers of CO2 emissions due to energy consumption of industrial enterprises above the designated size in 82 cities in China's coastal regions from 2005 to 2020 based on the CO2 emissions and socioeconomic data Exploration of the spatial data analysis methodology and the LMDI model. The results showthat the energy-related CO2 emissions of industrial enterprises above the designated size in China's coastal areas generally show a fluctuating upward trend, while some cities show a steady growth trend to a peak and then decline a slow decline

What specific improvements should the authors consider regarding the methodology? What further controls should be considered?

The authors should be more specific when presenting the contribution of this study.

To better support the selection of the LMDI method to break down the drivers that affect CO2 emissions, compare with other methods. Include validation of the selected proposal.

What is the reason for the selection of the study period 2005 - 2020?

Regarding the growth in the number of cities with ultra-high carbon emissions, explore the reasons, describe the trends and analyze their impact on the environment.

Are the conclusions consistent with the evidence and arguments presented and do they address the main question posed?

The conclusions section is similar to the analysis of results. It is suggested to simplify the points of view in the results analysis section and highlight the key points in the conclusions section of the document.

The limitation and future investigations of what has been done should be considered.

Common sense conclusions have been included and not an important conclusion of the investigation. A more technical analysis should be carried out and supported by some of the conclusions, only the information is given and not the why.

It is important to compare the results with other investigations or similar models.

Are the references appropriate?

There are very important investigations that could be included; these other investigations mention different models or methodologies that would give greater importance to what has been done

Please include any additional comments on the tables and figures.

Figures 1 and 2 are not very clear. Where does the data in Table 1 come from?

 

Author Response

Dear reviewer,

Thank you very much for your comments and professional advice. These opinions help to improve academic rigor of our article. Based on your suggestion and request, we have made corrected modifications on the revised manuscript. Furthermore, we would like to show the details as follow：

1. What is the main question addressed by the research?

This paper analyzes the evolution patterns and drivers of CO₂ emissions due to energy consumption of industrial enterprises above designated size in 82 cities in China's coastal regions from 2005 to 2020.

Although the document maintains an order in its structure, written logically and clearly, there are still some minor errors in the format of the text:

1.1 In the "Literature Review" section there is little information on the key cities of the coastal region, it is suggested that the authors carry out additional functions to guarantee the importance of the information that they want to disclose.

2. Authors should clearly explain the reason for the selection of coastal cities and the indices of the influencing factors.

2.1 In the analysis of the "spatial and temporal evolution of CO₂ emissions", too much emphasis is placed on the northern, central and southern regions, and it is suggested to analyze the most important or traditional cities to specify the information.

2.2 Do you consider the topic original or relevant in the field? Does it address a specific gap in the field?

2.3 China's carbon emissions account for about a quarter of the world's total greenhouse gas emissions. Considering the serious situation of global warming, it is necessary to reveal the spatial and temporal differences and analyze the indirect effects of carbon emissions between regions.

2.4 The growth in the number of cities with high carbon emissions is one of the most important reasons for describing trends and analyzing their impact on the environment.

2.5 Authors should clearly explain the reason for the selection of coastal cities and the indices of the influencing factors. What is the reason to analyze the spatial and temporal evolution of the coastal areas?

3. What does it add to the subject area compared with other published material?

This paper analyzes the spatial and temporal evolution patterns and drivers of CO₂ emissions due to energy consumption of industrial enterprises above the designated size in 82 cities in China's coastal regions from 2005 to 2020 based on the CO₂ emissions and socioeconomic data Exploration of the spatial data analysis methodology and the LMDI model. The results show that the energy-related CO₂ emissions of industrial enterprises above the designated size in China's coastal areas generally show a fluctuating upward trend, while some cities show a steady growth trend to a peak and then decline a slow decline

4. What specific improvements should the authors consider regarding the methodology? What further controls should be considered?

4.1 The authors should be more specific when presenting the contribution of this study.

4.2 To better support the selection of the LMDI method to break down the drivers that affect CO₂ emissions, compare with other methods. Include validation of the selected proposal.

4.3 What is the reason for the selection of the study period 2005 - 2020?

4.4 Regarding the growth in the number of cities with ultra-high carbon emissions, explore the reasons, describe the trends and analyze their impact on the environment.

5. Are the conclusions consistent with the evidence and arguments presented and do they address the main question posed?

5.1 The conclusions section is similar to the analysis of results. It is suggested to simplify the points of view in the results analysis section and highlight the key points in the conclusions section of the document.

5.2 The limitation and future investigations of what has been done should be considered.

5.3 Common sense conclusions have been included and not an important conclusion of the investigation. A more technical analysis should be carried out and supported by some of the conclusions, only the information is given and not the why.

5.4 It is important to compare the results with other investigations or similar models.

6. Are the references appropriate?

There are very important investigations that could be included; these other investigations mention different models or methodologies that would give greater importance to what has been done

7. Please include any additional comments on the tables and figures.

Figures 1 and 2 are not very clear. Where does the data in Table 1 come from?

Response

1. Dear reviewer, thank you very much for your suggestion. In response to your question, we would like to respond to your question "What are the main questions addressed by the study". This paper analyzes the evolution of CO₂ emissions caused by energy consumption of industrial enterprises above designated size in 82 cities in China's coastal region from 2005 to 2020, partly aiming at reflecting the trend of CO₂ emissions in each city through the data of energy CO₂ emissions in each city, and partly aiming at discussing the reasons for the change of CO₂ emissions caused by the energy consumption of industrial enterprises above designated size in each city, so as to help each city adjust the energy structure and industrial structure from the root, and promote the development of "industrial structure above designated size". The purpose of this study is to help each city to adjust the energy structure and industrial structure of industrial enterprises above designated size from the root, so as to promote the realization of the goal of "double carbon".

The complete modifications are in the Discussion first paragraph (Pages 14-15, Pages 543-548) of the revised manuscript.

1.1 According to your suggestion, we have added relevant literature on key cities in the coastal region in the "Literature Review" section to echo with the following section. Thank you again for your suggestions.

The complete modifications are in the introduction and References of the revised draft (Page 2 of Introduction, line 79 “Penultimate line of the second paragraph”, References 10-13).

2. Dear reviewer, thank you very much for your suggestion. Following your suggestion in agreement with other reviewers, we have added in the third paragraph of the introduction the reasons for the selection of coastal cities and the indicators for the five influencing factors.

The complete modifications are in the Introduction (Page 2, lines 46-50, Page 3, lines 106-116, Page 3, lines 141-148) of the revised manuscript.

2.1 In response to your suggestion, we have paid particular attention to the revision of the section on "Spatial and Temporal Evolution of CO₂ Emissions", and we have added a specific analysis of the different changes in each region over time, as reflected in the key cities, to highlight the importance of the key cities.

The complete modifications are in the "3.1 Characterization of the temporal evolution of CO₂ emissions" section of the revised manuscript. Second paragraph（Pages 7-8）.

2.2 In response to this issue raised by you, we believe that this study is original and relevant to the field of this research, firstly, in the field of carbon emissions, there are very few studies on China's coastal regions as a whole at the city level, and secondly, there are fewer studies cross-fertilizing the research methods of geography with those of economics, and the LMDI method, although very widely used, is still a very effective method to analyze the influencing factors. However, there are still many shortcomings in this study, and in future research we hope to be more mature and perfect.

2.3 According to your suggestion, we have made a comparative analysis of the three coastal regions in the section of "Characteristics of the temporal and spatial evolution of carbon dioxide emissions".

The complete modifications are in the Results and Analysis (Page 7, lines 287-292) of the revised manuscript.

2.4 According to your suggestion, we have added the reasons for the increase in the number of cities with high carbon emissions and their impact on the environment of the region.

The complete modifications are in the Results and Analysis (Page 8, lines 319-323) of the revised manuscript.

2.5 This suggestion was also made by other reviewers. We have carefully combined your suggestion with those of other reviewers and revised it carefully. In the introduction, we added the reason for choosing Chinese coastal cities in the first paragraph of the background and significance of the study, and in the third paragraph, we added the reason for choosing the indicators of the influencing factors and the reason for analyzing the spatial and temporal evolution of the coastal areas. Thank you again for your suggestions.

The complete modifications are in the Introduction (Page 2, lines 46-50, Page 3, lines 106-116, Page 3, lines 141-148) of the revised manuscript.

3. Dear reviewer, thank you very much for your suggestion. In response to your questions, we would like to respond here. Compared with other published materials, on the one hand, this study this study makes up for the status quo of fewer studies at the city level in China's coastal regions due to the lack of data, and on the other hand, it breaks the status quo of previous studies that were dominated by estimation in terms of data, and improves the precision of the data.
4. Dear reviewer, thank you very much for your suggestion. Based on your suggestions, we have added the relevant contents of the policy recommendations.

The complete modifications are in the Conclusions (Last paragraph, Page 17) of the revised manuscript.

4.1 In response to your suggestion, we have added a new section called "Discussion" to show the contributions of this study in concrete terms.

The complete modifications are in the Discussion (First paragraph, Page 15, lines 545-551) of the revised manuscript.

4.2 In response to your and other reviewers' suggestions, we have added to the Introduction section the reasons for choosing the LDMI method over other methods.

The complete modifications are in the Introduction (Pages 3, lines 141-148) of the revised manuscript.

4.3 In response to your query, we have addressed this in the "Data Sources" section of the article. On the one hand, we chose 2005-2020 as the study period because 2005 is a nodal point of China's CO₂ emissions, and the changes before 2005 are relatively small, so this is the base period, which has a certain degree of reference, on the other hand, because the data of this study are basically based on the data of each city's statistical department, and the data of some cities have not been updated in the last two years, so in order to ensure the unity and accuracy of the data, we chose 2005-2020 as the study period.

The complete modifications are in the Data sources (Page 4, lines 170-173) of the revised manuscript.

4.4 According to your suggestions, we have added the reasons for the increase in the number of cities with ultra-high carbon emissions and analyzed their impact on the environment. Thank you again for your suggestions.

The complete modifications are in the Results and Analysis (Page 8, lines 319-323) of the revised manuscript.

5. Dear reviewer, thank you very much for your suggestion. In response to your questions, we have revised the content of the conclusions, and the issues mentioned have been largely resolved.

5.1 According to the unanimous suggestion of you and several other reviewers, we have simplified the "Conclusion", focusing on the key points of the study and highlighting the four main findings of the study; at the same time, at your suggestion, we have added a "Discussion" section before the "Conclusion" to summarize the findings of the paper and to explain the reasons for the growth of the number of cities with high carbon emissions. At the same time, at your suggestion, we have added a "Discussion" section before the "Conclusion", which explains in detail the research contribution, analysis of the findings and limitations of this paper.

The complete modifications are in the Conclusions (Pages 16, lines 635-651) of the revised manuscript.

5.2 Based on your valuable suggestion, we have added this section to the "Discussion" section.

The complete modifications are in the Discussion (Page 16, lines 618-625) of the revised manuscript.

 

5.3 In response to your question about common sense conclusions, we are ashamed to say that we have revised it carefully and added some technical analyses.

The complete modifications are in the Conclusion (Page 16, lines 635-637) and Discussion of the revised manuscript.

5.4 As per your suggestion, we have considered comparing the results with previous data, but due to the small number of comparators, we have shown less, and we will continue to improve and apply this suggestion to future research. Thank you again for your suggestions.

6. Dear reviewer, thank you very much for your suggestion. In response to your question, we have once again added and adjusted the references to emphasize the importance of methodology in the research conducted. Thank you again for your suggestions.

The complete modifications are in the Introduction of the revised manuscript.

 

7. Dear reviewer, thank you very much for your suggestion. According to your suggestion, we have adjusted the clarity of Figures 1 and 2 to see if they meet the criteria. In addition, we have explained the sources of the standard coal conversion factors and CO₂ emission factors in the lower text of Table 1. Thank you again for your suggestions.

The complete modifications are in the Methods, Results and Analysis (Page 5, lines 203-208, Page 9 and page 11) of the revised manuscript.

 

Dear reviewer, special thanks to you for your good comments. The other changes are mainly about the grammars and spellings, so we didn’t mark them. We tried our best to improve the manuscript and made some changes in the manuscript according to your and other reviewers’ suggestions. These changes will not influence the content and framework of the paper. We appreciate for Reviewers’ warm work earnestly, and hope that the correction will meet with approval. Once again, thank you very much for your comments and suggestions.

Reviewer 6 Report

SUSTAINABILITY-2560911

With pleasure, I have reviewed the manuscript of the manuscript of the article entitled “Analysis of the spatial and temporal evolution of energy-related CO₂ emissions in China’s coastal areas and the drivers of industrial enterprises above designated size – The case of 82 cities”.

The paper deals with the evolution of energy-related CO₂ emissions in the China’s coastal region between 2005 and 2020, analysing different techno-economic aspects by means of the logarithmic mean divisa indexes and a statistical analysis by using the Moran’s index.

In conclusion, I recommend the article for publication in Sustainability after Major Revisions according to the following comments:

1.      P1, L19 and L33: Please, clarify the meaning of the acronyms the first time they appear. For instance, LMDI in line 19 and CPC in line 33.

2.      P2: I suggest adding a paragraph devoted to the comparison of other studies in other regions, for instance: Shao S. et al., Renew. sustain. energy rev. 2016, 55, 516-536 (DOI: 10.1016/j.rser.2015.10.081).

3.      P4, L166-L192: Please, check the references because there are some errors: [Error! Reference source not found.] in lines 166, 168, 171 and 192. Please, check the whole manuscript.

4.      P5, Table 1: In the title of the 3^rd and 6^th columns there is a spelling error: “fator” instead of “factor”.

5.      P5, L201-202: In the sentence: “The local autocorrelation local spatial autocorrelation was used…” I think there is a repetition that should be deleted.

6.      P7, L257-L260: I suggest subdividing the CO₂ emission classes as follows: very low, low, medium, high, very high and ultra-high. I think that comparatives (i.e., “lower” and “higher”) should not be used as adjectives.

7.      P8, Figure 1: Please, improve the quality and readability of the images.

8.      P8, Table 2: Please, add the equations for the evaluation of Moran’s Index, Z-value and p-value.

9.      P12, L429: If I correctly interpreted the meaning of the ΔD value, a negative value would mean that the inverse of the GDP decreased and so the GDP increased. Hence, is the average economic status of the people improving?

10.   P14: As CO₂ emissions are rapidly increasing due to the increased development of companies, are there any systems to control or contain CO₂ emissions and other pollutants into the atmosphere and into the sea? Is there a sustainable development plan for companies? What could you suggest doing?

 

11.   Lastly, I warmly recommend a careful revision of the English grammar and of the sentences in the whole manuscript.

I recommend a careful revision of the English language.

Author Response

Dear reviewer,

Thank you for your letter and the constructive comments on this article in your busy schedule. All of us authors have carefully read the comments that you have given us, and have discussed and revised each of these issues. The following is my list of revisions. In addition, we have resubmitted a new manuscript in the revised state, with the revisions highlighted in red. If there are any incorrect answers or questions in the manuscript, please do not hesitate to let us know.

With pleasure, I have reviewed the manuscript of the manuscript of the article entitled “Analysis of the spatial and temporal evolution of energy-related CO₂ emissions in China’s coastal areas and the drivers of industrial enterprises above designated size – The case of 82 cities”.

The paper deals with the evolution of energy-related CO₂ emissions in the China’s coastal region between 2005 and 2020, analysing different techno-economic aspects by means of the logarithmic mean divisa indexes and a statistical analysis by using the Moran’s index.

In conclusion, I recommend the article for publication in Sustainability after Major Revisions according to the following comments:

1. P1, L19 and L33: Please, clarify the meaning of the acronyms the first time they appear. For instance, LMDI in line 19 and CPC in line 33.
2. P2: I suggest adding a paragraph devoted to the comparison of other studies in other regions, for instance: Shao S. et al., Renew. sustain. energy rev. 2016, 55, 516-536 (DOI:10.1016/j.rser.2015.10.081).
3. P4, L166-L192: Please, check the references because there are some errors: [Error! Reference source not found.] in lines 166, 168, 171 and 192. Please, check the whole manuscript.
4. P5, Table 1: In the title of the 3rd and 6th columns there is a spelling error: “fator” instead of “factor”.
5. P5, L201-202: In the sentence: “The local autocorrelation local spatial autocorrelation was used…” I think there is a repetition that should be deleted.
6. P7, L257-L260: I suggest subdividing the CO₂ emission classes as follows: very low, low, medium, high, very high and ultra-high. I think that comparatives (i.e., “lower” and “higher”) should not be used as adjectives.
7. P8, Figure 1: Please, improve the quality and readability of the images.

8.P8, Table 2: Please, add the equations for the evaluation of Moran’s Index, Z-value and p-value.

9. P12, L429: If I correctly interpreted the meaning of the ΔD value, a negative value would mean that the inverse of the GDP decreased and so the GDP increased. Hence, is the average economic status of the people improving?
10. P14: As CO₂ emissions are rapidly increasing due to the increased development of companies, are there any systems to control or contain CO₂ emissions and other pollutants into the atmosphere and into the sea? Is there a sustainable development plan for companies? What could you suggest doing?

Lastly, I warmly recommend a careful revision of the English grammar and of the sentences in the whole manuscript.

Response

1. Dear reviewer, thank you very much for your suggestion. Based on your suggestion, we have added the meanings of the acronyms that appear for the first time. Thank you again for your suggestions.

The complete modifications are in the Introduction (Page 1, lines 19-20, 33) of the revised manuscript.

 

2. Dear reviewer, thank you very much for your suggestion. Based on your valuable suggestions, we immediately found this reference paper recommended by you "Using an extended LMDI model to explore techno-economic drivers of energy-related industrial CO emission changes: A case study for Shanghai (China)2" and browsed it carefully. We can see that this article firstly introduces the methodology and explains the methodology, then in the second paragraph; it compares the indicators of the influencing factors with other data, and then tells the background, reasons and significance of Shanghai as the research object. The article is very logical and has a greater reference value for the writing of the introduction of this study. Based on this article, this paper tells the second paragraph of the introduction about the source of the LMDI model, the use of research in various fields, and adds the reasons for choosing this method in comparison with other methods. Thank you again for your suggestions.

3. Thank you for your careful scrutiny, based on your suggestions, we have checked and corrected the reference format.

The complete modifications are in the Introduction (Paragraphs 1-4, Pages 1-3) of the revised manuscript.

4. Thank you for your careful scrutiny, we apologize for our own carelessness, we have corrected the spelling errors and double-checked the entire manuscript.

The complete modifications are in the Research Methodology (Page 5, Table 1, line 210) of the revised manuscript.

5. Thank you for your careful scrutiny and we apologize for our own carelessness. Based on your suggestions, we have removed the repetitions with errors.

The complete modifications are in the Research Methodology (Page 5, lines 212-216) of the revised manuscript.

6. Dear reviewer, thank you very much for your suggestion. Based on your valuable suggestions, we have subdivided the CO₂ emission levels into: Very Low, Low, Medium, High, Very High and Ultra High.

The complete modifications are in the Results and Analysis (Page 7, lines 295-297) of the revised manuscript.

7. Dear reviewer, thank you very much for your suggestion. Based on your suggestions, we have improved the quality of Figure 1 in terms of clarity and readability.

The complete modifications are in the Results and Analysis (Page 9, Figure 1) of the revised manuscript.

8. Dear reviewer, thank you very much for your suggestion. In response to your suggestion, we have added formulas for evaluating the global spatial autocorrelation analysis and local spatial autocorrelation analysis methods.

The complete modifications are in the Research Methodology (Pages 5-6, lines 213-241) of the revised manuscript.

9. Dear reviewer, thank you very much for your suggestion. In response to your question, we would like to reply that ΔD index refers to the inverse of gdp per capita, and in this study, we substitute it for labor productivity, which refers to the ratio of the labor output created by a worker in a certain period of time to his/her corresponding labor consumption. That is, the labor efficiency of a worker to produce a certain product. Here ΔD has been showing a negative effect, indicating a decrease in the number of workers or an increase in efficiency, and in addition the increase in labor productivity helps to reduce energy intensity, which to a certain extent helps to reduce the CO₂ emissions of industrial enterprises above a certain scale. Therefore it does mean that the inverse of GDP decreases and therefore GDP increases, but it may be an improvement in the average economic situation of the people, and this aspect will be taken into account more in future studies.

10. Dear reviewer, thank you very much for your suggestion. In response to your suggestion, we have added in the policy recommendations section recommendations for sustainable development of companies in relation to the "dual carbon" target.

The complete modifications are in the Conclusions (Page 17, lines 668-673) of the revised manuscript.

11. Dear reviewer, thank you very much for your suggestion. According to your suggestions and those of other reviewers, we uploaded the manuscript to the official MDPI touch-up platform, and invited professional English editors to touch up the whole manuscript. The touch-up report has been issued.

Dear reviewer, special thanks to you for your good comments. The other changes are mainly about the grammars and spellings, so we didn’t mark them. We tried our best to improve the manuscript and made some changes in the manuscript according to your and other reviewers’ suggestions. These changes will not influence the content and framework of the paper. We appreciate for Reviewers’ warm work earnestly, and hope that the correction will meet with approval. Once again, thank you very much for your comments and suggestions.

Author Response File: Author Response.docx

Round 2

Reviewer 4 Report

The manuscript is well organized and the summary is well supported by the results. Overall, I suggest it can be accepted for publication in this journal current form.

Minor editing of English language required

Reviewer 6 Report

The authors have answered all the reviewers’ comments and improved the overall quality of their manuscript. Therefore, I recommend the acceptance of the manuscript for publication in Sustainability.