Submit to this Journal Review for this Journal Propose a Special Issue

Article Menu

Share Help Cite Discuss in SciProfiles

Open AccessReview

Peer-Review Record

Progress, Challenges, and Strategies for China’s Natural Gas Industry Under Carbon-Neutrality Goals

Processes 2024, 12(8), 1683; https://doi.org/10.3390/pr12081683

by Hongfeng Tang^1,2, Yuanjiang Yu^3,* and Qinping Sun³

Reviewer 1: Anonymous

Reviewer 2: Anonymous

Reviewer 3: Anonymous

Reviewer 4: Anonymous

Processes 2024, 12(8), 1683; https://doi.org/10.3390/pr12081683

Submission received: 29 June 2024 / Revised: 30 July 2024 / Accepted: 5 August 2024 / Published: 12 August 2024

(This article belongs to the Section Energy Systems)

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

1. The introduction section could be enhanced by adding more references to strengthen the background information.

2. It would be beneficial to follow the journal's reference format for consistency and clarity, ensuring the references is in the correct order.

3. It might be helpful to tabulate the values in the tables for better readability and understanding.

4. The conclusion could be modified to provide a more comprehensive summary of the findings.

Author Response

Please see the attachment for more details.

Response for Reviewer 1 :

Thank you for your detailed review and valuable suggestions. We have addressed your comments and made the necessary revisions to the manuscript.

For introduction enhancement, we have significantly increased the number of references in the introduction to enhance the background information and provide a robust foundation for the discussion on China's dual carbon goals and their implications for the natural gas industry. The revised introduction includes specific data on emissions reductions, energy consumption trends, and the role of natural gas in energy transitions. We have also ensured the content is more detailed and comprehensive, with a logical flow and removal of jargon to maintain accessibility.

For reference formatting, we have revised all references to follow the journal's format for consistency and clarity. We have ensured that the references are in the correct order as required by the journal.

For table formatting, based on your suggestion, we have revised the format of the tables to improve readability and understanding.

Thank you again for your assistance. We look forward to your further review. The following is the point-by-point response for your suggestion.

Point-by-Point Response to Reviewer

1.The introduction section could be enhanced by adding more references to strengthen the background information.

Answer: Thanks for your suggestion. The number of references has been significantly increased to strengthen the background information and provide a more robust foundation for the discussion of the dual carbon goals and their implications for China's natural gas industry. Moreover, the content has been expanded to provide a more detailed and comprehensive overview of the carbon neutrality goals, the advantages of natural gas, and the current state and potential of the natural gas industry. This includes specific data on emissions reductions, energy consumption trends, and the role of natural gas in energy transitions. Meanwhile, the revised introduction is more concise and coherent, ensuring that each paragraph flows logically into the next. Jargon has been removed to maintain a professional tone and ensure accessibility to a broad audience. By highlighting the systematic, comprehensive, and timely nature of the research, the revised introduction underscores the importance of understanding the latest progress in the natural gas industry and its implications for China's energy transition under the dual carbon goals.

These changes collectively enhance the introduction, making it more informative, evidence-based, and aligned with the publishing standards of PROCESSES. Here is the revised introduction along with an explanation of the changes made:

The Chinese government has put forward the goal of "reaching peak carbon dioxide emissions by 2030 and realizing carbon neutrality by 2060" (carbon peaking and carbon neutrality goals, which are referred to as the dual carbon goals)[1-5]. Carbon emissions associated with the energy industry are mainly derived from coal, oil, natural gas, biomass, etc. [1-3]. Carbon sinks, including absorption by forests, can be equally balanced with carbon capture, utilization, and storage to achieve carbon neutrality [1, 3, 6, 7].

Since 1921, global natural gas production has risen from 20 billion cubic meters to 4.08 trillion cubic meters in 2023 [1-5]. From 1921 to 1950, the U.S. produced 90% of the world's natural gas. Production expanded to Europe, the former Soviet Union, the Mid-dle East, and North Africa from 1951 to 1970 [1,3]. Between 1971 and 2005, five major production regions emerged: North America, Russia, the Middle East, Asia-Pacific, and Africa. Post-2006, global natural gas production grew rapidly[6-7]. The experiences of European and American countries have shown that natural gas is the priority choice in terms of energy saving and emissions reductions, as well as energy transition [3, 5, 8]. The United States has vigorously implemented a strategy of "replacing coal with gas" [9, 10]. Natural gas consumption increased from 23% to 31% from 2005 to 2019, while renewable energy consumption increased from 1% to 5% [1]. As a result, carbon dioxide emissions have decreased significantly, with global CO₂ emissions per unit of GDP dropping by 18.1% from 2000 to 2019, peaking in 2007 [1, 4, 11]. Previous investigations have indicated that the new dual carbon goals will accelerate low-carbon energy transition, change the development mode of the energy industry [10], and promote sustainable, high-quality growth in the natural gas sector, leading to reduced emissions [5, 11, 12]. In addition to the advantages of cleanliness and high efficiency, natural gas also has the advantages of strong peak shifting abilities, stable and reliable power generation, and up to 90% availability in terms of time, which can fully make up for the intermittent and variable nature of renewable energy sources, such as wind and solar energy. It is the most realistic choice to realize "cleaner and decarbonization" energy structures[1-5,13-15]. These attributes effectively compensate for the intermittent and variable nature of renewable energy sources like wind and solar, making natural gas the most practical choice for achieving cleaner and decarbonized energy structures [13-15]. Therefore, natural gas will continue to play a crucial role in ensuring energy security and supporting structural transformation, making it the primary choice in the low-carbon development of fossil energy [9-13]. At present, China's natural gas industry has entered a new stage of leapfrog development. In the 21st century, it has become the fourth-largest gas producer in the world [1]. Against the backdrop of a complex geopolitical environment, considering the security of the energy supply, the goal of carbon peaking, and the vision of carbon neutrality, the development of China's natural gas industry will be unprecedented in terms of development space and opportunities [1, 3, 14]. In order to form a comprehensive understanding of China's natural gas industry concerning the above objectives, recent research results provided by relevant scholars were summarized. We also discuss the prospects for the development of China's natural gas industry in the context of “carbon neutrality”[15].

Zou summarized the history and achievements of China's natural gas industry, analyzed its current status and challenges involved in transitioning to green and low-carbon energy, and proposed a development strategy for the industry [1]. Jian reviewed the history, current status, trends, and issues of China's natural gas industry, analyzed the prospects from supply and demand perspectives, and proposed reasonable and sustainable strategic measures and suggestions [16]. Gao collected, organized, and analyzed the indicators, data, and dynamics of China's natural gas industry in 2023 in order to help the industry’s high-quality development and encourage Chinese-style modernization [17]. Sun analyzed the natural gas industry chain using industrial organization and market system theories [18]. He reviewed market structure, institutional rules, and regulations, identified key issues, and proposed optimization strategies [18]. Zhou considered the changes in the development environment and supply and demand situation in the process of energy transition and clarified the business focus and development path in China's natural gas industrial chain [15]. Dong compared the natural gas markets in the U.S. and China from 2000 to 2015. Their study revealed increased development in the natural gas supply chain and proposed countermeasures for future development in both countries [19]. Dai compared China with major global gas producers, analyzing China's natural gas resources, production growth, and remaining recoverable reserves [20]. Their analysis predicts that China's annual natural gas production will reach 250×10⁹ m³ by 2025 [20]. Jin analyzed the development positioning and potential of the natural gas industry based on the results of natural gas demand forecasts by different domestic and international organizations [21].

Most scholars have only analyzed and researched a certain link in China's natural gas industry chain and the supply and demand situation under the background of “carbon neutrality” [1-15]. However, there is a lack of summarized analysis of the latest achievements in China's natural gas industry in the context of “carbon neutrality”. It cannot provide guidance for the subsequent sustainable development of the natural gas industry. To this end, this article reviews and evaluates the latest developments, important theories, key technologies, and key achievements in upstream exploration and development through interdisciplinary tracking research and comprehensive elaboration. It focuses on analyzing the exploration and development situation in China's natural gas industry, the size of the production capacity potential, and the synergistic effect of the whole industrial chain, including the production–supply–storage–marketing system. This is of great significance in terms of improving our understanding of China's natural gas industry and is conducive to further promoting the energy substitution of natural gas in energy reform.

The specific contribution of this paper is to summarize the development highlights of China's natural gas industry and analyze the supply potential of China's natural gas industry so as to be able to judge China's natural gas development prospects and targets in the context of peak carbon and carbon-neutral strategies. It provides decision-making support for government departments and industry organizations to formulate policies and standards, which is of comparatively important theoretical and practical significance.

It would be beneficial to follow the journal's reference format for consistency and clarity, ensuring the references is in the correct order.

Answer: Thank you for your valuable feedback. Thank you for your valuable feedback on our manuscript. We have revised all the references to follow the journal's format for consistency and clarity, and we have ensured that they are in the correct order as required.

It might be helpful to tabulate the values in the tables for better readability and understanding.

Answer: Thank you for your valuable suggestion to improve the readability and understanding of our tables. Based on your feedback, we have revised the table format.

The revised table is shown as the following:

Table 1. The first CBM exploration and development demonstration projects in China [15].

Companies	Primary construction contents					The expected
	Production area (km²)	Production reserves （×10⁸ m³）	Number of wells	Production capacity (×10⁸m³/y)	Daily output of single well （×10⁴m³）			Annual output （×10⁸m³）
					Daily output of single well （×10⁴m³）			2025	2026
					Vertical Well		Horizontal Well	2025	2026
PetroChina Coalbed Methane Co., Ltd	85.81	238.52	79	10			4	10	10
China United Coalbed Methane Company	158.66	370.9	2861	13.7	0.3		1.3	12.3	13.7
Shanxi Jinyang Fenghui Coal Industry Co., Ltd	89.75	160.32	231	5	0.3		1	3	5.1
Sinopec East China Oil & Gas Company	6.7	10.7	9	0.69	1		3	0.5	0.3

The conclusion could be modified to provide a more comprehensive summary of the findings.

Answer: Thank you very much for your comments. In response to your suggestions, we have refined the conclusions of the last chapter. The details are as follows:

China's natural gas industry has achieved important results in resource evaluation, resource reserves, capacity improvement, theoretical technology, and industrial chain development. It has not only realized leapfrogging development relating to unconventional gas but has also met the continuously growing demand for natural gas.

This paper digs deep into resource distribution and technological development from geographical and technical levels. It has been found that natural gas exploration has recently experienced a number of major discoveries and undergone new breakthroughs. Starting from the latest engineering planning aspects, it argues for the sustainability of China's natural gas industry. Based on the SWOT analysis method, it has been demonstrated that the development of the natural gas industry is promising under the goal of “double carbon” from the perspectives of advantages, disadvantages, opportunities, and challenges. On this basis, it is predicted that PetroChina will continue to be the main natural gas producer in the future, taking into account the business plan of PetroChina. Finally, based on the strategic combination scheme given by SWOT, four strategic measures and development suggestions for the development of China's natural gas industry are proposed, providing theoretical support for the subsequent development of China's natural gas industry and decision-making support for the government and enterprises.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

Tang et al. delivered a paper on “Progress, Challenges, and Strategies for China's Natural Gas Industry Under Carbon Neutrality Goals”. The authors extensively described the past and current state of the natural gas industry of China and discussed the further challenges towards carbon neutrality. Moreover, they used the SWOT method to better analyze the development prospects of China's natural gas industry. Overall, the paper is interesting and could be published in Processes after major revision. The main problem of this paper is in formatting and referencing.

The abstract. It is written well but still contains grammatical errors. For example, in Line 22, “Then, based on this, the SWOT method was used to analyze the development prospects of China's natural gas industry. And proposed development goals.” You cannot start the sentence with “And”.

Line 26. Check the sentence: “Provide planning support and management reference for the development of China's natural gas industry”

The introduction is relevant and provides some background. However, the authors should better highlight the novelty of this work in the last paragraph of this section. Please check the other works in the field and revise the introduction.

Lines 39-76. References are missing.

Lines 79-104. References are missing.

Line 114. “large-scale deep-water gas fields[40].” Why reference [40] is here and where is the rest? Revise.

Line 130. “Widespread deep-buried faulting–dissolution reservoirs and fractured– 129 cavernous reservoirs have contributed greatly to oil and gas exploration in deep basins [4] 130 (Zou, 2020).”. Check the references.

Line 135. “for successive gas generation and shale gas exploration was 1.35–3.5% [8, 25, 39, 41-44].” Please avoid using an excessive amount of the references. One or two is enough.

Line 145. “be observed and horizontal permeability was significantly high (Fig. 2;[13, 17, 28]). Five” Where are the rest of the references?

Line 150. “and gas resources, while also promoting their strategic development [40, 42, 43].” Where is the rest of the references?

Line 151-215. The ref-s are missing.

Line 254-259. Again the same problem. Excessive references.

Line 278. “(4) Sinopec Weirong Gas Field was to establish production capacity of 30×108 m3 [3] 278 (Gao et al., 2021). “ Check the references. Revise the sentence.

Line 280-288. Can you please present your calculations for the average annual growth rate of gas production? No need to include it in the paper, only in the response so we can check it.

Line 290 and the rest of the article. The larger part of the paper doesn’t contain references. Please use Mendeley or other reference managers to appropriately cite the literature. Even if it is not in English or you’re using information available online, you should still cite them. Otherwise, it raises ethical concerns.

Also, some grammatical and syntax errors were observed. Please check the paper for typos and the article should be proofread by a native speaker.

For example, in line 211 you use the name “Dzungar Basin” and in other lines, you use “Junggar Basin”. Which one is correct? Please revise the paper carefully.

Line 713. Regarding the SWOT analysis, I liked the analysis you provided. You should enhance it by presenting it graphically. Prepare a figure or schematics and use the bullet points for each section (adv., disadv., etc). This is going to be the main takeaway from your article.

Line 765. Please check the following article: https://www.sciencedirect.com/science/article/pii/S0921344921005681

“Challenges toward carbon neutrality in China: Strategies and countermeasures”. Please compare China's natural gas industry with other countries in tabular form.

Comments on the Quality of English Language

Some grammatical and syntactical errors were observed. Please check the paper for typos, and it should be proofread by a native speaker. Examples have been provided in the comments.

Author Response

Please see the attachment for detailed responses. Responses in the attachment is more comfortable to review.

Response for Reviewer 2:

Thank you for your detailed review and valuable suggestions. We have addressed your comments and made the necessary revisions to the manuscript.

Introduction Enhancement: We included an analysis of the global development changes in the natural gas industry (inserted in the second paragraph of the Introduction). This added content outlines the historical and geographical expansion of natural gas production from 1921 to the present, highlighting key developments in the United States, Europe, the former Soviet Union, the Middle East, and North Africa. It also describes the emergence of major natural gas production regions and the rapid growth in global natural gas production post-2006.

Global Natural Gas Production Data: We added annual natural gas production statistics from 1920 to 2023 for eight key countries, which have been organized into a new Table 1 and placed in the Introduction section. This table provides a comprehensive overview of the historical production trends in these countries, emphasizing their contributions to the global natural gas industry.

Reference Formatting: We have thoroughly reviewed and standardized all references to ensure they comply with the submission guidelines of the journal. All cited references are accurately listed and correctly cited within the text using Mendeley reference management software to maintain consistency and accuracy.

Table Formatting: Based on your suggestion, we have revised the format of the tables to improve readability and understanding.

Grammatical and Syntactical Improvements: We have had the entire manuscript professionally edited and thoroughly reviewed for grammatical and syntactical errors, making necessary corrections to improve clarity and readability.

SWOT Analysis Presentation: In response to your suggestion, we have enhanced the SWOT analysis by presenting it graphically. We prepared a figure and used bullet points for each section (advantages, disadvantages, etc.), making it a clear and main takeaway of our article.

Comparison with Other Countries: We included a comparative analysis of China's natural gas industry with other countries in tabular form, based on the content of references [1-7].

We believe these revisions have significantly improved the quality and readability of our paper. We hope you are satisfied with our revisions and look forward to the potential acceptance of our paper for publication in Processes.

Thank you again for your assistance. We look forward to your further review. The following is the point-by-point response for your suggestion.

Point-by-Point Response to Reviewer

Tang et al. delivered a paper on “Progress, Challenges, and Strategies for China's Natural Gas Industry Under Carbon Neutrality Goals”. The authors extensively described the past and current state of the natural gas industry of China and discussed the further challenges towards carbon neutrality. Moreover, they used the SWOT method to better analyze the development prospects of China's natural gas industry. Overall, the paper is interesting and could be published in Processes after major revision. The main problem of this paper is in formatting and referencing.

Answer: Thank you for your valuable feedback on our paper titled “Progress, Challenges, and Strategies for China's Natural Gas Industry Under Carbon Neutrality Goals.” We are delighted that you found our paper interesting and acknowledged the importance of our research. Based on your comments, we have made the following revisions:

For formatting issues, we have carefully reviewed and corrected the formatting issues in the paper to ensure a clear and consistent structure. Specific modifications include adjusting the formatting of titles and subtitles, standardizing fonts and paragraph styles, and organizing the layout of figures and tables.

For referencing issues, we have thoroughly reviewed and standardized all references to ensure they comply with the submission guidelines of the journal Processes. We have ensured that all cited references are accurately listed and correctly cited within the text.

Thank you again for your review and suggestions. We believe these revisions have significantly improved the quality and readability of our paper. We hope you are satisfied with our revisions and look forward to the potential acceptance of our paper for publication in Processes.

The abstract. It is written well but still contains grammatical errors. For example, in Line 22, “Then, based on this, the SWOT method was used to analyze the development prospects of China's natural gas industry. And proposed development goals.” You cannot start the sentence with “And”.

Answer: Thanks for your suggestion. Thank you for pointing out the grammatical errors in the abstract. We have revised the sentence to improve its clarity and correctness. The corrected sentence is as follows:

"Building on this analysis, we employed the SWOT method to examine the development prospects of China's natural gas industry and to propose development goals."

Additionally, we have thoroughly reviewed the entire abstract to ensure logical coherence and to correct any grammatical issues. The revised abstract is exhibited as the following:

In recent years, the Chinese government has introduced a series of energy-saving, emission-reducing, and environmentally protective policies. These policies have gradually decreased the proportion of high carbon-emitting energy consumption, such as coal, in China's energy structure. The proportion of natural gas consumption as a clean energy source has been increasing year by year. In the future, with the deepening decarbonization of the energy structure, the applied scope of natural gas utilization will expand, increasing demand. Therefore, this study first evaluated the development of China's natural gas industry from the perspectives of development evolution, technological applications, and industry achievements. Secondly, based on the current situation of conventional and unconventional natural gas development, both resources and technological potential were analyzed. By taking several typical projects in the natural gas industry as examples, medium- and long-term prospects for natural gas development were planned and predicted. Building on this analysis, we employed the SWOT method to examine the development prospects of China's natural gas industry and propose development goals. Finally, based on top-level design considerations and previous research analysis, suggestions and measures were proposed for technology implementation, regional layout, industrial chain collaboration, and support policies. These recommendations aim to provide planning support and management references for the development of China's natural gas industry.

Line 26. Check the sentence: “Provide planning support and management reference for the development of China's natural gas industry”

Answer: Thanks for your suggestion. This sentence has been corrected as “These recommendations aim to provide planning support and management references for the development of China's natural gas industry.”

The introduction is relevant and provides some background. However, the authors should better highlight the novelty of this work in the last paragraph of this section. Please check the other works in the field and revise the introduction.

Answer: Thank you very much for your comments. We have improved the introduction content. The specific content is as follows:

Since 1921, global natural gas production has risen from 20 billion cubic meters to 4.08 trillion cubic meters in 2023 [1-5]. From 1921 to 1950, the U.S. produced 90% of the world's natural gas. Production expanded to Europe, the former Soviet Union, the Mid-dle East, and North Africa from 1951 to 1970 [1,3]. Between 1971 and 2005, five major production regions emerged: North America, Russia, the Middle East, Asia-Pacific, and Africa. Post-2006, global natural gas production grew rapidly [6-7]. The experiences of European and American countries have shown that natural gas is the priority choice in terms of energy saving and emissions reductions, as well as energy transition [3, 5, 8]. The United States has vigorously implemented a strategy of "replacing coal with gas" [9, 10]. Natural gas consumption increased from 23% to 31% from 2005 to 2019, while renewable energy consumption increased from 1% to 5% [1]. As a result, carbon dioxide emissions have decreased significantly, with global CO₂ emissions per unit of GDP dropping by 18.1% from 2000 to 2019, peaking in 2007 [1, 4, 11]. Previous investigations have indicated that the new dual carbon goals will accelerate low-carbon energy transition, change the development mode of the energy industry [10], and promote sustainable, high-quality growth in the natural gas sector, leading to reduced emissions [5, 11, 12]. In addition to the advantages of cleanliness and high efficiency, natural gas also has the advantages of strong peak shifting abilities, stable and reliable power generation, and up to 90% availability in terms of time, which can fully make up for the intermittent and variable nature of renewable energy sources, such as wind and solar energy. It is the most realistic choice to realize "cleaner and decarbonization" energy structures[1-5,13-15]. These attributes effectively compensate for the intermittent and variable nature of renewable energy sources like wind and solar, making natural gas the most practical choice for achieving cleaner and decarbonized energy structures [13-15]. Therefore, natural gas will continue to play a crucial role in ensuring energy security and supporting structural transformation, making it the primary choice in the low-carbon development of fossil energy [9-13]. At present, China's natural gas industry has entered a new stage of leapfrog development. In the 21st century, it has become the fourth-largest gas producer in the world [1]. Against the backdrop of a complex geopolitical environment, considering the security of the energy supply, the goal of carbon peaking, and the vision of carbon neutrality, the development of China's natural gas industry will be unprecedented in terms of development space and opportunities [1, 3, 14]. In order to form a comprehensive understanding of China's natural gas industry concerning the above objectives, recent research results provided by relevant scholars were summarized. We also discuss the prospects for the development of China's natural gas industry in the context of “carbon neutrality”[15].

The rest of this study is organized as follows: Chapter 1 is based on long-term tracking of the upstream and downstream of China's natural gas industry, the latest data, comprehensive research and literature, and comprehends the evolution of China's natural gas industry, evaluating current technological developments and industry achievements. Chapter 2 analyzes the future supply potential of China's natural gas industry in terms of resources, technology, and engineering planning. Chapter 3 utilizes the SWOT approach to uncover the opportunities and challenges for the future development of China's natural gas industry, thereby proposing development prospects and targets. Chapter 4 puts forward the development strategies and suggestions for China's natural gas industry under the dual-carbon goal from the aspects of technology, planning, industry chain synergy, and policy one by one. Chapter 5 is the conclusion.

Lines 39-76. References are missing.

The experiences of European and American countries have shown that natural gas is the priority choice in terms of energy saving and emissions reductions, as well as en-ergy transition [3, 5, 8]. The United States has vigorously implemented a strategy of "re-placing coal with gas" [9, 10]. Natural gas consumption increased from 23% to 31% from 2005 to 2019, while renewable energy consumption increased from 1% to 5% [1]. As a result, carbon dioxide emissions have decreased significantly, with global CO2 emissions per unit of GDP dropping by 18.1% from 2000 to 2019, peaking in 2007 [1, 4, 11]. Previous investigations have indicated that the new dual carbon goals will accelerate low-carbon energy transition, change the development mode of the energy industry [10], and pro-mote sustainable, high-quality growth in the natural gas sector, leading to reduced emis-sions [5, 11, 12]. In addition to the advantages of cleanliness and high efficiency, natural gas also has the advantages of strong peak shifting abilities, stable and reliable power generation, and up to 90% availability in terms of time, which can fully make up for the intermittent and variable nature of renewable energy sources, such as wind and solar energy. It is the most realistic choice to realize "cleaner and decarbonization" energy structures[1-5,13-15]. These attributes effectively compensate for the intermittent and variable nature of renewable energy sources like wind and solar, making natural gas the most practical choice for achieving cleaner and decarbonized energy structures [13-15]. Therefore, natural gas will continue to play a crucial role in ensuring energy security and supporting structural transformation, making it the primary choice in the low-carbon development of fossil energy [9-13]. At present, China's natural gas industry has entered a new stage of leapfrog development. In the 21st century, it has become the fourth-largest gas producer in the world [1]. Against the backdrop of a complex geopolitical environ-ment, considering the security of the energy supply, the goal of carbon peaking, and the vision of carbon neutrality, the development of China's natural gas industry will be un-precedented in terms of development space and opportunities [1, 3, 14]. In order to form a comprehensive understanding of China's natural gas industry concerning the above objectives, recent research results provided by relevant scholars were summarized. We also discuss the prospects for the development of China's natural gas industry in the context of “carbon neutrality”[15].

Zou summarized the history and achievements of China's natural gas industry, an-alyzed its current status and challenges involved in transitioning to green and low-carbon energy, and proposed a development strategy for the industry [1]. Jian re-viewed the history, current status, trends, and issues of China's natural gas industry, an-alyzed the prospects from supply and demand perspectives, and proposed reasonable and sustainable strategic measures and suggestions [16]. Gao collected, organized, and analyzed the indicators, data, and dynamics of China's natural gas industry in 2023 in order to help the industry’s high-quality development and encourage Chinese-style modernization [17]. Sun analyzed the natural gas industry chain using industrial organ-ization and market system theories [18]. He reviewed market structure, institutional rules, and regulations, identified key issues, and proposed optimization strategies [18]. Zhou considered the changes in the development environment and supply and demand situation in the process of energy transition and clarified the business focus and devel-opment path in China's natural gas industrial chain [15]. Dong compared the natural gas markets in the U.S. and China from 2000 to 2015. Their study revealed increased devel-opment in the natural gas supply chain and proposed countermeasures for future de-velopment in both countries [19]. Dai compared China with major global gas producers, analyzing China's natural gas resources, production growth, and remaining recoverable reserves [20]. Their analysis predicts that China's annual natural gas production will reach 250×109 m³ by 2025 [20]. Jin analyzed the development positioning and potential of the natural gas industry based on the results of natural gas demand forecasts by different domestic and international organizations [21].

Most scholars have only analyzed and researched a certain link in China's natural gas industry chain and the supply and demand situation under the background of “car-bon neutrality”[1-15]. However, there is a lack of summarized analysis of the latest achievements in China's natural gas industry in the context of “carbon neutrality”. It cannot provide guidance for the subsequent sustainable development of the natural gas industry. To this end, this article reviews and evaluates the latest developments, im-portant theories, key technologies, and key achievements in upstream exploration and development through interdisciplinary tracking research and comprehensive elaboration. It focuses on analyzing the exploration and development situation in China's natural gas industry, the size of the production capacity potential, and the synergistic effect of the whole industrial chain, including the production–supply–storage–marketing system. This is of great significance in terms of improving our understanding of China's natural gas industry and is conducive to further promoting the energy substitution of natural gas in energy reform.

Lines 79-104. References are missing.

Answer：Thank you for your thorough review and valuable feedback. We have carefully reviewed lines 79-104 and have added the missing references. The specific modifications are as:

Divided in terms of annual production and accumulated proven reserves, the development of China's natural gas industry can be roughly divided into three stages [1]:

The initial stage lasted for 28 years (1949-1977) [1, 4, 22]. China's natural gas industry was initially developed in the Sichuan Basin, primarily by the China National Petroleum Corporation (hereinafter referred to as PetroChina), which is engaged in exploration, development, and industrial production. The output gradually increased from 0.1×10⁸m³ to 100×10⁸m³, with proven nationwide geological reserves of less than 2000×10⁸m³[5, 23, 24].

The second stage was the slow growth stage (1978-2000) [1, 4, 22]. In these 22 years, China's annual natural gas production steadily increased to 303×10⁸m³, and the total proven geological reserves of natural gas amounted to 3.4×10¹²m³, mainly consisting of dissolved gas and gas reservoirs produced by PetroChina [4]. China National Offshore Oil Corporation (CNOOC) was established in February 1982 [25]. In July 1998, China National Petroleum and Chemical Corporation Limited was established as a wholly state-owned holding company [5]. After that, some provincial enterprises, central enterprises, and other private small and medium-sized enterprises were established, e.g., Shaanxi Yanchang Petroleum (Group) Co., Ltd. (Yanchang Petroleum) and Sinochem Petroleum Exploration and Development Co., Ltd. (Sinochem Petroleum), jointly participating in the exploration, development, and production of natural gas [24].

The third stage was the rapid growth stage (2001-2022)[1, 4, 22]. The annual average natural gas production growth was 83.4 ×10⁸m³in these 21 years, reaching 2200×10⁸m³ in 2022 [1]. The cumulative proven reserves amounted to 19.61×10¹²m³. The annual increase was ~100-fold in the past seven years, with an average growth rate of ~10% [4]. PetroChina, Sinopec, and CNOOC developed rapidly during this stage, while other oil companies developed in parallel (Fig.1, [1, 4, 24]).

Line 114. “large-scale deep-water gas fields [40].” Why reference [40] is here and where is the rest? Revise.

Answer: Thank you for your suggestion. The original reference [40] mentioned the development status of large-scale deep-water gas fields, such as those in the Sichuan Basin, Songliao Basin, Ordos Basin, and Qaidam Basin, making it appropriate to cite here. Based on your suggestion, we have added the following references to further support the statement that "uplifts within cratons controlled the distribution of large-scale gas fields, platform edges control the zonal distribution of reefs and shoals, and passive continental edges control the development and distribution of large-scale deep-water gas fields." The additional references are as follows:

Klein, G.D., Probable sequential arrangement of depositional systems on cratons. Geology 1982, 10, (1), 17-22.
Zhao, W.; Wang, Z.; Jiang, H.; Fu, X.; Jiang, Q., Exploration status of the deep Sinian strata in the Sichuan Basin: Formation conditions of old giant carbonate oil/gas fields. Natural Gas Industry B 2020.
Shi, Z.; Zhou, T.; Guo, W.; Liang, P.; Cheng, F., Quantitative Paleogeographic Mapping and Sedimentary Microfacies Division in a Deep-water Marine Shale Shelf: Case study of Wufeng-Longmaxi shale, southern Sichuan Basin, China. 2022, 40, (6), 1728-1744.
Line 130. “Widespread deep-buried faulting–dissolution reservoirs and fractured– 129 cavernous reservoirs have contributed greatly to oil and gas exploration in deep basins [4] 130 (Zou, 2020).”. Check the references.

Answer: Thank you for your suggestion. Since this paragraph is not closely related to the main idea of the paper, it has been deleted.

Line 135. “for successive gas generation and shale gas exploration was 1.35–3.5% [8, 25, 39, 41-44].” Please avoid using an excessive amount of the references. One or two is enough.

Answer: Thank you for your valuable feedback. We have revised the sentence to limit the number of references cited, ensuring conciseness and relevance. The revised sentence now reads: “Mechanisms of or-ganic pore development and shale gas release were proposed, where the optimal thermal maturity for successive gas generation and shale gas exploration was 1.35–3.5% [29].”

Line 145. “be observed and horizontal permeability was significantly high (Fig. 2;[13, 17, 28]). Five” Where are the rest of the references?

Answer: Thank you for your reminder. We have cited related references in this paragraph. Citations have been corrected. The specific citation information for the paper is as follows:

It had a silicon-rich and calcareous-rich paleontology, e.g., graptolite and algae. Shale gas was primarily produced from intervals with a thickness of 20-40 m, where abundant beddings and microfractures could be observed and horizontal permeability was significantly high (Fig. 2;[13-17, 28]). Five "sweet spots" were identified, with a potential area of 2×10⁴ km² and recoverable resources of 10×10¹² m³, and national shale gas demonstration zones were built, e.g., Weiyuan, Changning, Zhaotong, and Fuling [30, 32, 33].

[30] Shi, Z.; Zhou, T.; Guo, W.; Liang, P.; Cheng, F., Quantitative Paleogeographic Mapping and Sedimentary Mi-crofacies Division in a Deep-water Marine Shale Shelf: Case study of Wufeng-Longmaxi shale, southern Sichuan Basin, China. 2022.

[32] Wang, H.; Shi, Z.; Sun, S.; Zhang, L., Characterization and genesis of deep shale reservoirs in the first Member of the Silurian Longmaxi Formation in southern Sichuan Basin and its periphery. Oil & Gas Geology 2021, 42, (1), 66-75.

[33] Wang, H.; Shi, Z.; Zhao, Q.; Liu, D.; Sun, S.; Guo, W.; Liang, F.; Lin, C.; Wang, X., Stratigraphic framework of the Wufeng-Longmaxi shale in and around the Sichuan Basin, China: Implications for targeting shale gas. Energy Geo-science 2020, 1, (3-4), 124-133.

Line 150. “and gas resources, while also promoting their strategic development [40, 42, 43].” Where is the rest of the references?

Answer: We apologize for the oversight in our reference citations. The correct reference citation for this statement should be [30-34]. The original marking was incorrect due to a citation error.

Line 151-215. The ref-s are missing.

Answer：Thank you for your meticulous review and valuable feedback. We have carefully examined lines 151-215 and have added the missing references. The specific changes are as:

Since the 13th Five-Year Plan, geophysical technologies have been extensively developed and applied, significantly enhancing the natural gas industry [34]. Advanced seismic acquisition techniques (broadband, wide azimuth, and high density) for complex surface and underground structures, along with low-frequency vibrations and structural imaging, have improved imaging and reservoir prediction accuracy [35-38]. This has greatly supported the exploration and development of natural gas, notably in the Keshen and Kelasu structures in the Kuqa Depression and central Sichuan Basin [39-41]. Drilling technologies for complex lithologies and deep gas reservoirs have advanced, significantly reducing drilling periods (e.g., from 387 to ~300 days in the Kuqa foreland thrust belt and from 301 to 175 days in the Gaomo structure) while also extending horizontal section lengths [42]. Enhanced log interpretation technologies for complex lithology, tight reservoirs, and shale gas reservoir have increased interpretation accuracy by 5–10% compared to the 12th Five-Year Plan [34, 43]. The development of multi-dimensional imaging log technologies and CIFLog 2.0 software has formed the basis of core technologies used in over 80% of CNPC's oilfields [44]. Geophysical methods have greatly improved imaging and reservoir prediction accuracy, which are crucial for identifying and exploiting unconventional "sweet spots" [39-41]. Effective fracturing technologies for unconventional reservoirs, such as those in the Kuqa Depression and central Sichuan Basin, have led to significant breakthroughs [39-42]. Volumetric fracturing technologies for horizontal wells have increased individual well production by more than threefold and some by more than fivefold [41, 42, 45].

1.3 Analysis of the evaluation of industry development results

With theoretical innovation and technological breakthroughs, China's natural gas industry has accomplished the following eight achievements since the 13th Five-Year Plan.

1.3.1 Exploration and development areas

Recently, conventional gas exploration and development focusing on foreland thrust belts, marine carbonate rocks, deep and ultra-deep reservoirs, the "four new" domains, etc., have achieved considerable major discoveries and breakthroughs, promoting gas reserves and production [26, 31, 46, 47]. Unconventional gas (shale gas, tight gas, and coalbed methane (CBM)) exploration and development, mainly focused on shale gas, coalbed methane, and tight gas, achieved rapid increases in terms of reserves and production and establishing a strong position for subsequent development [48-53]. At present, natural gas exploration and development have been continuously expanded, leading to diverse gas reservoir types being made available and doubling resource potential [4, 23, 24], for example, from structural reservoirs to lithologic reservoirs, from single-carbonate reservoirs to conventional clastic reservoirs, loose sandstone reservoirs, low-permeability tight reservoirs, volcanic reservoirs, shale gas, and coal gas [54, 55]. The targets have expanded from shallow reservoirs to deep and ultra-deep reservoirs, transforming from conventional natural gas to both conventional and unconventional gas [23, 47].

The natural gas industry has expanded from regions predominately located in the Sichuan Basin to nationwide, including Shaanxi Province, Gansu Province, Xinjiang Province, Qinghai Province, Yunnan Province, and three provinces in East and North China [1]. Since the first national oil and gas resource assessment in 1986, natural gas resources have increased by 10 ×10¹²m³ every 10 years (Fig.2, [6, 7]).

With breakthroughs in unconventional gas, the latest oil and gas resource assessment suggests that the total recoverable conventional and unconventional gas resources in China have increased to 111.5 ×10¹² m³ [1].

China's natural gas exploration is based on strategic, global, and forward-looking objectives, highlighting the utilization of new fields, new zones, new layers, and new types, with remarkable exploration results [1, 4, 5]. For 19 consecutive years, China's new geological reserves of natural gas have exceeded 5,000×10⁸ m³, and the cumulative geological reserves of natural gas in three basins, namely Sichuan, Ordos and Tarim, have exceeded 2×10¹²m³, while the cumulative geological reserves of natural gas in the basins of Songliao, Qaidam, East China Sea, Bohai Bay, Qiongnangdong, Ingekai, Junggar, and Zhujiangkou, as well as the Bohai Sea, have exceeded 1,000×10⁸ m³, laying the foundation for the rapid growth of natural gas production and resources [49, 56, 57]. Proven natural gas reserves have provided a resource base for the rapid development of the natural gas industry and capacity enhancement.

Line 254-259. Again the same problem. Excessive references.

Answer: Thank you for your suggestion. After re-evaluating the references cited, we have selected more appropriate references for the paragraph in lines 254-259. The revised references are as follows:

Natural gas production in China reached 2300×10⁸m³ in 2023, with the average annual yield increasing by 100×10⁸m³ for 8 consecutive years [28-29]. Three major gas regions—the Sichuan Basin, Ordos Basin, and Tarim Basin—were the main contributors to this increase in production [12,30]. Since 2018, the increase in production has accounted for 70% of the total value in China [31-34].

Line 278. “(4) Sinopec Weirong Gas Field was to establish production capacity of 30×10⁸ m³ [3] 278 (Gao et al., 2021). “Check the references. Revise the sentence.

Answer: Thanks for you suggestion. Since this paragraph is not closely related to the main idea of the paper, it has been deleted.

Line 280-288. Can you please present your calculations for the average annual growth rate of gas production? No need to include it in the paper, only in the response so we can check it.

Answer: Here is the data for the Annual production chart of natural gas by type for China National Petroleum Corporation:

Year	Anuual Production of conventional gas (10⁸m³)	Anuual Production of tight gas (10⁸m³)	Anuual Production of shale gas (10⁸m³)	Anuual Production of coalbed Methane (10⁸m³)
2000	183.0	0.0	0.0	0.0
2001	206.0	0.0	0.0	0.0
2002	225.0	0.0	0.0	0.0
2003	248.0	0.0	0.0	0.0
2004	280.0	5.0	0.0	0.0
2005	356.0	9.0	0.0	0.0
2006	428.0	12.0	0.0	0.0
2007	511.0	29.0	0.0	0.0
2008	553.0	65.0	0.0	0.0
2009	577.0	105.0	0.0	1.0
2010	597.0	125.0	0.0	3.0
2011	590.0	162.0	0.0	4.0
2012	593.0	200.0	0.1	6.0
2013	633.0	246.0	1.0	9.0
2014	666.0	275.0	2.0	12.0
2015	654.0	272.0	13.0	15.0
2016	669.0	268.0	28.0	16.0
2017	711.0	273.0	30.0	18.0
2018	736.0	296.0	43.0	19.0
2019	757.0	330.0	80.0	21.0
2020	808.0	360.0	116.0	22.0
2021	846.0	380.0	129.0	23.0
2022	855.0	431.0	139.0	30.0

（1）To calculate the average annual growth rate of CNPC's conventional gas production from 2000 to 2022, follow these steps:

① Collect the Data

Here are the annual production values for conventional gas from 2000 to 2022:

2000: 183 × 10⁸ m³
2022: 855 × 10⁸ m³

② Use the Compound Annual Growth Rate (CAGR) Formula

The CAGR formula is used to calculate the average annual growth rate over a period:

Where:

is the final value (2022 production of conventional gas)
is the initial value (2000 production of conventional gas)
is the number of years
- Plug in the Values

Substitute these values into the CAGR formula:

The average annual growth rate of CNPC's conventional gas production from 2000 to 2022 is approximately 7.3%.

（2）To calculate the average annual growth rate of CNPC's tight gas production from 2004 to 2022, follow these steps:

① Collect the Data

Here are the annual production values for tight gas from 2004 to 2022:

2000: 5 × 10⁸ m³
2022: 431 × 10⁸ m³

② Use the Compound Annual Growth Rate (CAGR) Formula

The CAGR formula is used to calculate the average annual growth rate over a period:

Where:

is the final value (2022 production of tight gas)
is the initial value (2004 production of tight gas)
is the number of years
- Plug in the Values

Substitute these values into the CAGR formula:

The average annual growth rate of CNPC's tight gas production from 2004 to 2022 is approximately 26.7%.

（3）To calculate the average annual growth rate of CNPC's shale gas production from 2012 to 2022, follow these steps:

① Collect the Data

Here are the annual production values for shale gas from 2012 to 2022:

2012:1 × 10⁸ m³
2022: 139 × 10⁸ m³

② Use the Compound Annual Growth Rate (CAGR) Formula

The CAGR formula is used to calculate the average annual growth rate over a period:

Where:

is the final value (2022 production of shale gas)
is the initial value (2012 production of shale gas)
is the number of years
- Plug in the Values

Substitute these values into the CAGR formula:

The average annual growth rate of CNPC's shale gas production from 2012 to 2022 is approximately 570%.

（4）To calculate the average annual growth rate of CNPC's coalbed methane production from 2009 to 2022, follow these steps:

① Collect the Data

Here are the annual production values for coalbed methane (CBM) from 2009 to 2022:

2012: 1 × 10⁸ m³
2022: 30 × 10⁸ m³

② Use the Compound Annual Growth Rate (CAGR) Formula

The CAGR formula is used to calculate the average annual growth rate over a period:

Where:

is the final value (2022 production of CBM)
is the initial value (2012 production of CBM)
is the number of years
- Plug in the Values

Substitute these values into the CAGR formula:

The average annual growth rate of CNPC's coalbed methane production from 2009 to 2022 is approximately 43.8%.

Line 290 and the rest of the article. The larger part of the paper doesn’t contain references. Please use Mendeley or other reference managers to appropriately cite the literature. Even if it is not in English or you’re using information available online, you should still cite them. Otherwise, it raises ethical concerns.

Answer: Thank you for your detailed review and valuable suggestions. We have addressed your comments and made the necessary revisions in the manuscript.

Specifically, we have added numerous references throughout the paper (please see the revised MS: Line 290 and the rest of the article) to ensure all cited content is properly referenced. We used Mendeley reference management software to maintain consistency and accuracy in our citations. Even for non-English references or information sourced online, we have included proper citations to avoid any ethical concerns.

Also, some grammatical and syntax errors were observed. Please check the paper for typos and the article should be proofread by a native speaker.

Answer: Thank you for your suggestion. Following your recommendation, we have had the entire manuscript professionally edited by MDPI's language editing service (see attached certificate). Additionally, the authors have thoroughly reviewed the manuscript for grammatical and syntactical errors, making necessary corrections to improve clarity and readability.

For example, in line 211 you use the name “Dzungar Basin” and in other lines, you use “Junggar Basin”. Which one is correct? Please revise the paper carefully.

Answer: Thank you for pointing out the inconsistency. We have standardized the name to "Junggar Basin" throughout the entire manuscript to ensure consistency.

19.Line 713. Regarding the SWOT analysis, I liked the analysis you provided. You should enhance it by presenting it graphically. Prepare a figure or schematics and use the bullet points for each section (adv., disadv., etc). This is going to be the main takeaway from your article.

Answer: Thank you very much for your comments. In response to your suggestion, we have added section 3.5. The details are as follows:

3.5 SWOT Matrix Analysis of China's Natural Gas Industry Development

Focusing on the internal and external environment of China's natural gas industry, to analyze the strengths (S), weaknesses (W), opportunities (O), and threats (T) of China's natural gas industry, and the combination can produce four different strategies, namely, the S-O strategy, the W-O strategy, the S-T strategy, and the W-T strategy, as shown in the following Table 2 and Fig.11.

Table 2 SWOT Strategy Map of China's Natural Gas Industry

external environment

internal environment

Advantage (S)

1. Unconventional natural gas resources have enormous potential.

2. Nearly 50% of the proven natural gas reserves have not yet been utilized

3. Rapid development of conventional and unconventional natural gas geological theories and exploration and development engineering technologies

4. Following the natural gas development strategy of accelerating the development of the western region, developing the sea area, and expanding the eastern region

Weaknesses (W)

1. Natural gas pipelines still cannot meet market demand.

2. With the expansion of natural gas consumption, there is an urgent need to improve the capacity for gas storage and peak shaving.

3. 3D seismic, drilling, seismic interpretation, logging and other technologies cannot adapt to deep wells and complex terrain layers.

4. The comprehensive evaluation, three-dimensional exploration, sweet spot identification, and geological engineering integration of unconventional gas are relatively weak, which restricts the large-scale commercial development of unconventional natural gas.

Opportunity (O)

1. Relevant policies and planning documents support.

2. There is a high demand in large domestic and international markets.

3. Technical support for technological innovation and digital transformation.

S-O Strategy

(Utilize internal strengths and take advantage of external opportunities)

W-O Strategy

(Give full play to external advantages, customer service internal disadvantages)

Challenge (T)

1. Single development model and lack of market competitiveness

2. Investment is gradually becoming conservative, leading to an increase in natural gas production and a slowdown in the construction of gas supply and consumption facilities

3. There are problems with the natural gas pricing mechanism. Diversified development increases its economic costs.

S-T Strategy

(Strengthen internal advantages and avoid external threats)

W-T Strategy

(Reduce internal disadvantages and avoid external threats)

Fig.10 SWOT analysis and deduction matrix of China's natural gas industry

Line 765. Please check the following article: https://www.sciencedirect.com/science/article/pii/S0921344921005681

Thank you for your reminder. We have referred to the article you provided and have specifically addressed two major issues in the rapid development of China's natural gas industry. We have reorganized Section 3.2 and added the article as a key reference. The revised Section 3.2 is as follows, with the newly added discussion highlighted in yellow:

Firstly, natural gas pipelines are still unable to meet market demand. The rapid expansion of natural gas consumption in China has outpaced the development of pipeline networks, leading to bottlenecks and supply issues [15, 21, 106]. The lack of adequate pipeline capacity restricts the efficient distribution of natural gas from production sites to consumers, hampering the overall growth and reliability of the industry[5]. When comparing this stage with that seen in Western developed countries reveals that there is a big gap between China and them in terms of the construction of underground natural gas storage and transportation pipelines [5, 21]. As of 2020, there are 120,000 kilometers of natural gas pipelines in service nationwide, with a primary pipeline capacity of 340 billion cubic meters/year, equivalent to 1/6 of that of the U.S., 1/10 of that of France, and 1/15 of that of Germany [15, 18]. Natural gas pipeline capacity is still insufficient, and there is not enough interconnection and interconnectivity, especially lagging behind in the construction of the "last kilometer" [15, 21, 106]. Particularly, the lag in the construction of the "last kilometer" restricts the demand of downstream user consumption [20]. Currently, the working volume of underground natural gas storage accounts for only 3.4% of China's natural gas consumption, compared to the world average of about 24% [15, 16, 21]. Among other things, issues such as pipeline construction, its interconnection, natural gas transmission and deployment capacity, and poor systematic and emergency response capacity for the transmission and distribution of natural gas have been major factors contributing to the tight supply and demand in the market seen in recent years [15, 17, 23]. This situation is exacerbated by extreme climatic conditions and the winter peak season for gas consumption. In addition, the provincial gas transmission and distribution pipeline networks are not developed to the same extent, and the regional fragmentation of gas transmission and distribution is a prominent contradiction [1, 23].

Secondly, gas storage and peaking capacity are insufficient. China's gas storage and peaking capacity are not sufficient to balance the fluctuations in supply and demand, especially during peak periods [16]. This lack of storage capacity means that the country is unable to store excess gas during periods of low demand and use it during high-demand periods, which leads to supply shortages and affects the stability of the natural gas supply [5]. At present, China has formed a gas storage capacity of 25 billion cubic meters, with a working gas volume of 14.7 billion cubic meters, accounting for only 4.5% of China's natural gas consumption, much lower than the international average of 12% to 15% [15]. In terms of imported LNG storage capacity, China's LNG receiving stations are few in number, small in size, and limited in storage capacity [5]. A single LNG receiving station typically supports storage tanks with a capacity of 160,000 cubic meters, which is far less than that of other LNG-importing countries like South Korea and Japan [15]. South Korea's largest Pyeongtaek LNG receiving terminal has 23 storage tanks, while Japan's Sleevepool LNG receiving station has 35 storage tanks [1, 23]. China's natural gas consumption has obvious seasonality, especially during the winter heating period in the north, leading to occasionally tight supplies [15, 17, 23]. With the expansion of natural gas consumption in the future, there is an urgent need to improve the capacity of gas storage and peaking [5].

“Challenges toward carbon neutrality in China: Strategies and countermeasures”. Please compare China's natural gas industry with other countries in tabular form.

Answer: Thank you very much for your comments. Based on the content of references [1-7], we made the following revisions: （1）We included an analysis of the global development changes in the natural gas industry (inserted in the second paragraph of the Introduction).（2）We added annual natural gas production statistics from 1920 to 2023 for eight key countries (organized into a new Table 1, placed in the Introduction section).

The added content regarding the global development changes in the natural gas industry is: Since 1921, global natural gas production has risen from 20 billion cubic meters to 4.08 trillion cubic meters in 2023 [1-5]. From 1921 to 1950, the U.S. produced 90% of the world's natural gas. Production expanded to Europe, the former Soviet Union, the Mid-dle East, and North Africa from 1951 to 1970 [1,3]. Between 1971 and 2005, five major production regions emerged: North America, Russia, the Middle East, Asia-Pacific, and Africa. Post-2006, global natural gas production grew rapidly [6-7].

The revised Table 1 is as following shown:

Table S1: Global natural gas annual output from 1920-2023.

Year	Global natural gas annual output（10¹²m³）								Year	Global natural gas annual output（10¹²m³）
Year	United Stated	Russia	Canada	Holland	Norway	Iran	Algeria	China	Year	United Stated	Russia	Canada	Holland	Norway	Iran	Algeria	China
1920.00	0.01	0.01	0.01	0.01	0.01	0.01	0.01	0.01	1972	0.61	0.82	0.89	0.95	0.95	0.99	0.99	1.00
1921.00	0.02	0.02	0.02	0.02	0.02	0.02	0.02	0.02	1973	0.58	0.82	0.88	0.95	0.95	1.00	1.01	1.02
1922.00	0.02	0.02	0.02	0.02	0.02	0.02	0.02	0.02	1974	0.54	0.80	0.88	0.94	0.94	1.00	1.01	1.02
1923.00	0.03	0.03	0.03	0.03	0.03	0.03	0.03	0.03	1975	0.54	0.82	0.89	0.97	0.97	1.03	1.04	1.06
1924.00	0.03	0.03	0.03	0.03	0.03	0.03	0.03	0.03	1976	0.54	0.85	0.92	1.00	1.01	1.06	1.07	1.08
1925.00	0.03	0.03	0.03	0.03	0.03	0.03	0.03	0.03	1977	0.54	0.88	0.95	1.01	1.02	1.09	1.09	1.11
1926.00	0.04	0.04	0.04	0.04	0.04	0.04	0.04	0.04	1978	0.55	0.92	1.00	1.08	1.09	1.15	1.16	1.19
1927.00	0.04	0.04	0.04	0.04	0.04	0.04	0.04	0.04	1979	0.55	0.95	1.02	1.09	1.11	1.16	1.17	1.20
1928.00	0.05	0.05	0.05	0.05	0.05	0.05	0.05	0.05	1980	0.53	0.96	1.02	1.09	1.11	1.17	1.18	1.21
1929.00	0.05	0.05	0.05	0.05	0.05	0.05	0.05	0.05	1981	0.49	0.95	1.03	1.08	1.11	1.16	1.17	1.21
1930.00	0.06	0.06	0.06	0.06	0.06	0.06	0.06	0.06	1982	0.45	0.94	1.00	1.08	1.10	1.14	1.16	1.21
1931.00	0.06	0.06	0.06	0.06	0.06	0.06	0.06	0.06	1983	0.49	1.02	1.09	1.16	1.17	1.23	1.25	1.29
1932.00	0.06	0.06	0.06	0.06	0.06	0.06	0.06	0.06	1984	0.47	0.88	0.97	1.04	1.06	1.11	1.13	1.18
1933.00	0.07	0.07	0.07	0.07	0.07	0.07	0.07	0.07	1985	0.45	0.91	0.99	1.04	1.06	1.13	1.15	1.19
1934.00	0.07	0.07	0.07	0.07	0.07	0.07	0.07	0.07	1986	0.47	0.96	1.04	1.10	1.13	1.19	1.22	1.27
1935.00	0.08	0.08	0.08	0.08	0.08	0.08	0.08	0.08	1987	0.48	1.01	1.11	1.16	1.18	1.25	1.29	1.33
1936.00	0.08	0.08	0.08	0.08	0.08	0.08	0.08	0.08	1988	0.49	1.04	1.15	1.20	1.23	1.30	1.35	1.39
1937.00	0.09	0.09	0.09	0.09	0.09	0.09	0.09	0.09	1989	0.50	1.08	1.19	1.25	1.27	1.35	1.41	1.44
1938.00	0.09	0.09	0.09	0.09	0.09	0.09	0.09	0.09	1990	0.50	1.08	1.18	1.26	1.28	1.36	1.42	1.46
1939.00	0.10	0.10	0.10	0.10	0.10	0.10	0.10	0.10	1991	0.51	1.08	1.20	1.26	1.30	1.38	1.45	1.49
1940.00	0.10	0.10	0.10	0.10	0.10	0.10	0.10	0.10	1992	0.51	1.07	1.18	1.27	1.29	1.37	1.44	1.48
1941.00	0.12	0.12	0.12	0.12	0.12	0.12	0.12	0.12	1993	0.52	1.08	1.21	1.28	1.31	1.41	1.47	1.52
1942.00	0.13	0.13	0.13	0.13	0.13	0.13	0.13	0.13	1994	0.53	1.06	1.21	1.27	1.29	1.42	1.49	1.53
1943.00	0.15	0.15	0.15	0.15	0.15	0.15	0.15	0.15	1995	0.53	1.08	1.23	1.30	1.34	1.47	1.55	1.59
1944.00	0.15	0.15	0.15	0.15	0.15	0.15	0.15	0.15	1996	0.53	1.06	1.20	1.27	1.31	1.45	1.53	1.59
1945.00	0.15	0.15	0.15	0.15	0.15	0.15	0.15	0.15	1997	0.53	1.07	1.22	1.29	1.34	1.48	1.57	1.64
1946.00	0.17	0.17	0.17	0.17	0.17	0.17	0.17	0.17	1998	0.54	1.07	1.23	1.29	1.33	1.50	1.60	1.65
1947.00	0.19	0.19	0.19	0.19	0.19	0.19	0.19	0.19	1999	0.54	1.07	1.23	1.29	1.34	1.51	1.63	1.69
1948.00	0.22	0.22	0.22	0.22	0.22	0.22	0.22	0.22	2000	0.55	1.08	1.24	1.31	1.35	1.54	1.65	1.72
1949.00	0.23	0.24	0.24	0.24	0.24	0.24	0.24	0.24	2001	0.54	1.07	1.24	1.30	1.37	1.55	1.67	1.73
1950.00	0.25	0.26	0.26	0.26	0.26	0.26	0.26	0.26	2002	0.54	1.10	1.27	1.33	1.39	1.59	1.71	1.77
1951.00	0.27	0.28	0.28	0.28	0.28	0.28	0.28	0.28	2003	0.52	1.10	1.26	1.33	1.41	1.61	1.73	1.81
1952.00	0.28	0.29	0.29	0.29	0.29	0.29	0.29	0.29	2004	0.51	1.10	1.26	1.32	1.40	1.60	1.74	1.82
1953.00	0.28	0.31	0.31	0.31	0.31	0.31	0.31	0.31	2005	0.52	1.12	1.29	1.36	1.44	1.63	1.77	1.86
1954.00	0.30	0.32	0.32	0.32	0.32	0.32	0.32	0.32	2006	0.53	1.14	1.30	1.37	1.44	1.65	1.80	1.92
1955.00	0.31	0.35	0.35	0.35	0.35	0.35	0.35	0.35	2007	0.56	1.16	1.33	1.39	1.49	1.70	1.85	1.98
1956.00	0.32	0.36	0.36	0.36	0.36	0.36	0.36	0.36	2008	0.58	1.12	1.27	1.33	1.42	1.64	1.80	1.93
1957.00	0.33	0.38	0.38	0.38	0.38	0.38	0.38	0.38	2009	0.61	1.19	1.34	1.41	1.51	1.72	1.93	2.09
1958.00	0.34	0.38	0.38	0.38	0.38	0.38	0.38	0.38	2010	0.65	1.26	1.40	1.46	1.56	1.76	2.00	2.16
1959.00	0.35	0.40	0.40	0.40	0.40	0.40	0.40	0.40	2011	0.67	1.27	1.41	1.48	1.59	1.79	2.04	2.21
1960.00	0.37	0.43	0.43	0.43	0.43	0.43	0.43	0.43	2012	0.69	1.29	1.44	1.50	1.59	1.81	2.07	2.25
1961.00	0.39	0.47	0.47	0.47	0.47	0.47	0.47	0.47	2013	0.72	1.31	1.46	1.53	1.61	1.85	2.10	2.30
1962.00	0.41	0.50	0.50	0.50	0.50	0.50	0.50	0.50	2014	0.76	1.34	1.49	1.53	1.64	1.88	2.14	2.35
1963.00	0.44	0.55	0.55	0.55	0.55	0.55	0.55	0.55	2015	0.73	1.32	1.48	1.53	1.62	1.87	2.13	2.34
1964.00	0.48	0.59	0.60	0.60	0.60	0.60	0.60	0.60	2016	0.72	1.33	1.47	1.53	1.63	1.88	2.15	2.38
1965.00	0.49	0.63	0.65	0.65	0.65	0.65	0.65	0.65	2017	0.75	1.37	1.55	1.60	1.72	1.98	2.24	2.51
1966.00	0.53	0.67	0.70	0.71	0.71	0.71	0.71	0.71	2018	0.84	1.50	1.68	1.72	1.82	2.10	2.38	2.66
1967.00	0.56	0.71	0.75	0.77	0.77	0.77	0.77	0.77	2019	0.91	1.60	1.76	1.79	1.88	2.18	2.45	2.77
1968.00	0.57	0.75	0.80	0.82	0.82	0.82	0.82	0.82	2020	0.90	1.56	1.71	1.74	1.86	2.14	2.40	2.74
1969.00	0.59	0.77	0.82	0.85	0.85	0.87	0.87	0.87	2021	0.93	1.63	1.80	1.83	1.92	2.23	2.51	2.87
1970.00	0.61	0.80	0.86	0.89	0.89	0.92	0.92	0.92	2022	0.96	1.60	1.77	1.79	1.89	2.21	2.50	2.87
1971.00	0.61	0.80	0.87	0.91	0.91	0.97	0.97	0.97	2023	0.97	1.59	1.76	1.79	1.88	2.20	2.49	2.86

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

Referee comments

Main Content

This manuscript focuses on the LNG industry in China under the Carbon Neutrality Goals. Regarding this topic, the authors evaluate the development of China’s natural gas industry and analyze the development of this particular industry. Besides, suggestions and measures were proposed from the government’s perspective.

However, I have multiple questions regarding this study. Therefore, a major revision should be conducted before the final decision can be made.

Major Comments

1. My first comment is about the writing of this manuscript. The language could be further polished.

In the abstract, Page 1 Line 23, “And proposed development goals.” This sentence seems to be isolated and abrupt. Please expand it to a full sentence or make it part of another sentence.

Page 2, Line 48, “In addition, in addition to the advantages of cleanliness and high efficiency…”.

Page 3, Line 52–55, “Therefore, natural gas in guaranteeing energy security and structural transformation will continue to assume the role of bridge and important support for energy transformation, is the primary choice of fossil energy low-carbon transformation and development.” This sentence should be rewritten.

Some of the content is not directly related to this manuscript.

2. My second comment is about the academic contribution. The current manuscript does not give a clear description of academic contributions. It is suggested to put a summary of what research gap does this paper fill.

3. My third comment is about the figures.

First is Figure 1, the current version conveys information in an inefficient way. Please reorganize this figure. Also, where do the arrows from the event boxes end? The figure seems to be incomplete.

Second, there are two figures entitled “Figure 3”, one at Page 6, “Fig 3. China National Petroleum Corporation's Natural Gas Branch Annual Production Chart” and the other one at Page 7, “Fig 3. Annual production chart of natural gas by type for China National Petroleum Corporation”.

Third, in Figure 3 at Page 6, what does “Chang qing” mean?

Fourth, in Figure 3 at Page 7, there are five areas in the area chart, but only four types of natural gases listed in the figure.

Minor comments

1. There are some typos in the current manuscript, including but not limited to:

Page 7, Line 285, “…methane production is 45.2%.In 2022…”.

Comments on the Quality of English Language

Extensive editing of English language required.

Author Response

Please see the attachment for detailed responses. Responses in the attachment is more comfortable to review.

Response for Reviewer 3：

Thank you for your detailed review and valuable suggestions. We have addressed your comments and made the necessary revisions to the manuscript. Firstly, we improved the language and grammar by revising isolated and abrupt sentences for clarity and coherence, correcting repeated phrases and redundant content, and condensing sections to remove verbose and less relevant information. For example, the sentence "And proposed development goals" has been expanded to "Building on this analysis, we employed the SWOT method to examine the development prospects of China's natural gas industry and propose development goals."

Secondly, we enhanced the content relevance and structure by integrating and summarizing sections that were previously verbose and less relevant, deleting detailed technical descriptions unrelated to natural gas, and removing parts focusing on oil exploration. Additionally, we added a paragraph summarizing the research gap filled by this paper, emphasizing the importance of analyzing China's natural gas industry within the context of carbon neutrality goals, which is now included at the end of the Introduction.

Thirdly, we reorganized and clarified figures and tables. We rephrased major events in Figure 1 for better clarity and corrected figure numbering and legends. Specifically, "Chang qing" in Figure 3 now clearly represents the Changqing Oil and Gas Field, and the areas in Figure 4 correctly represent the four types of natural gases discussed.

Lastly, we corrected all identified typos and grammatical errors, such as revising the sentence "…methane production is 45.2%. In 2022…" and adding a space after this sentence. We also enhanced the SWOT analysis by presenting it graphically and using bullet points for each section (advantages, disadvantages, etc.), making it a clear and main takeaway of our article.

Thank you again for your assistance. We look forward to your further review. The following is the point-by-point response for your suggestion.

Point-by-Point Response to Reviewer

Main Content

However, I have multiple questions regarding this study. Therefore, a major revision should be conducted before the final decision can be made.

Major Comments

My first comment is about the writing of this manuscript. The language could be further polished.

（1）In the abstract, Page 1 Line 23, “And proposed development goals.” This sentence seems to be isolated and abrupt. Please expand it to a full sentence or make it part of another sentence.

Answer: Thanks for your suggestion. As your suggestion, this sentence has been revised as “Building on this analysis, we employed the SWOT method to examine the development prospects of China's natural gas industry and propose development goals.”

（2）Page 2, Line 48, “In addition, in addition to the advantages of cleanliness and high efficiency…”.

Answer: Thanks for pointing out this mistake. This sentence has been revised as “In addition to the advantages of cleanliness and high efficiency, natural gas also has the advantages of strong peak shifting abilities, stable and reliable power generation, and up to 90% availability in terms of time, which can fully make up for the intermittent and variable nature of renewable energy sources, such as wind and solar energy.”

（3）Page 3, Line 52–55, “Therefore, natural gas in guaranteeing energy security and structural transformation will continue to assume the role of bridge and important support for energy transformation, is the primary choice of fossil energy low-carbon transformation and development.” This sentence should be rewritten.

Answer: Thanks for your suggestion. This sentence has been rewritten as “Therefore, natural gas will continue to play a crucial role in ensuring energy security and supporting structural transformation, making it the primary choice in the low-carbon development of fossil energy [9-13].”.

（4）Some of the content is not directly related to this manuscript.

Answer: In this revision, we addressed four types of unrelated content and made necessary amendments:

（1）First, some sections were summarized inappropriately and were too verbose, making them seem less relevant to the main topic. We revised these sections to integrate and condense the content, including:

① Section 1.2: We restructured the development process and latest theories of conventional and unconventional natural gas exploration. We removed exploration theories and discoveries less related to natural gas and provided a concise summary of key geophysical methods crucial for the natural gas industry, excluding detailed descriptions of specific geophysical methods.

② Section 1.3.3: We reduced details about the proven reserves and production of shale gas in specific basins and summarized the rapid development of unconventional natural gas in recent years.

（2）Second, we deleted overly detailed technical descriptions that were not closely related to the main topic, including:

① Section 2.2.1:

“The Bozi 9 well has provided high-yield oil and gas flows at depths of 7677-7761 m, with gas production of 70.5×10⁴m³/d and condensate production of 167 m³/d.”, were deleted.
Revised this sentence “The Cretaceous Yageliemu Formation was drilled by the Ketan 1 well in the Kela 2 structure; it was tested in the first quarter of 2023 at depths of 5151-5220 m, with nozzle of 8 mm and oil pressure of 62.86 MPa after fracturing, obtaining high-yield industrial gas flow of 52.7×10⁴m³/d (Fig.3).” to “The Ketan 1 well drilled into the Cretaceous Yageliemu Formation, achieving a high-yield industrial gas flow of 52.7×10⁴ m³/d (Fig. 3).”
“Investigation has shown that 5-30 m thick limestone deposits are widely distributed in the Taiyuan Formation of the Ordos Basin, sandwiched between coal seams No. 5 and No. 8” has been deleted.

② Section 2.2.2:

“The horizontal section of Nalin 1H is 1500 m in length, with coal seam thickness of 760 m.” This sentence has been deleted.
“For instance, the Daye 1, Zi 201, and Lei 1 wells in the Sichuan Basin.”This sentence has been removed.
“A model of shale deposition at rifts was subsequently established. The cumulative gas production exceeds 100×10⁴m³. ” This sentence has been deleted.

③ Original Section 2.3.5：Removed extraneous natural gas production forecast plans. “The production plan aims for 10×10⁸m³in 2025, 60×10⁸m³ in 2030, and 90×10⁸m³in 2035, comprehensively considering the time of submitting reserves, the progress of production testing and evaluation, the period of scheme preparation and approval, the period of construction and production, our understanding of new gas field development, etc.” The content from the original Sections 2.3.3 and 2.3.5, both discussing specific examples of natural gas exploration in the Sichuan Basin, was consolidated into Section 2.3.1 in the revised manuscript.

（3）Third, parts of the theoretical and exploration progress focused on "oil" rather than natural gas, and were removed, including:

① Section 2.2.1: “The daily oil output was 425 t, daily gas output was 15.8×10⁴m³, and daily light hydrocarbon production was 35 m³ under a nozzle of 7 mm and oil pressure of 81 MPa, indicating a typical reservoir with resource potential of 1×10⁸ t. ””The Hutan 1 well in the middle of the southern margin of the Junggar Basin first made a major breakthrough in its lower assemblages, with daily gas production of 61×10⁴ m³ and daily oil production of 106.3 m³ at 7367-7382 m. The proven gas resources amounted to 1090×10⁸ m³.””Thirdly, high-yield fault-controlled oil-rich zones were discovered. The daily oil production and gas production of the Yijianfang Formation at the Manshen 1 well were 624 t and 37×10⁴ m³, respectively, indicating great exploration potential of ultra-deep reservoirs associated with strike–slip fault zones as well as crannies and caves in the northern Tarim Basin. ” These sentences have been deleted. Meanwhile, excessive citations were also consolidated.

（4）Finally, we deleted repetitive and verbose sections:

① Section 2.2.1: Deleted a repetitive paragraph that reiterated new high-yield reservoirs drilled in the Cambrian Canglangpu Formation and other wells, as well as previous studies' suggestions on ultra-deep reservoir exploration.：“Furthermore, as mentioned above, new high-yield reservoirs were drilled in the Cambrian Canglangpu Formation of the Jiaotan 1 well in the Sichuan Basin, and high-yield gas flow was also obtained from deep-buried reservoirs at the Pengtan 1 well (Sichuan Basin) and Hutan 1 well (Junggar Basin), representing the exploration of new gas zones and gas fields. Previous studies suggested that the exploration of ultra-deep reservoirs with good resource potential should be strengthened [2, 6, 8, 13, 14, 16, 19, 36, 48, 50, 51].”

My second comment is about the academic contribution. The current manuscript does not give a clear description of academic contributions. It is suggested to put a summary of what research gap does this paper fill.

Answer: Thanks for your suggestion. The specific contribution of this paper is to summarize the highlights of the development results of China's natural gas industry, and analyze the supply potential of China's natural gas industry, so as to be able to judge China's natural gas development prospects and targets in the context of the peak carbon and carbon neutral strategies. It provides decision-making support for government departments and industry organizations to formulate policies and standards, which is of comparatively important theoretical and practical significance.

This paragraph has been added in the last of the Introduction.

My third comment is about the figures.

（1）First is Figure 1, the current version conveys information in an inefficient way. Please reorganize this figure. Also, where do the arrows from the event boxes end? The figure seems to be incomplete.

Answer: Thank you for your valuable feedback. We have made two key adjustments to the original Figure 1:

Major Events Rephrasing: We have rephrased the major events in the three development stages of the natural gas industry to highlight more representative milestones.
Formatting Adjustments: We have revised the formatting of the stage names and years to enhance clarity and emphasis on key points.

The modified Figure 1 is presented as follows:

Fig 1. Development stages of China's natural gas industry (Modified by [1]).

（2）Second, there are two figures entitled “Figure 3”, one at Page 6, “Fig 3. China National Petroleum Corporation's Natural Gas Branch Annual Production Chart” and the other one at Page 7, “Fig 3. Annual production chart of natural gas by type for China National Petroleum Corporation”.

Answer: Thank you for your careful review and valuable feedback. We apologize for the oversight regarding the figure numbering in our manuscript.

We have corrected this error and renamed the figures as follows:

On Page 6, the figure previously titled “Fig 3. China National Petroleum Corporation's Natural Gas Branch Annual Production Chart” is now titled “Fig 3. China National Petroleum Corporation's Natural Gas Branch Annual Production Chart”.

On Page 7, the figure previously titled “Fig 3. Annual production chart of natural gas by type for China National Petroleum Corporation” is now titled “Fig 4. Annual production chart of natural gas by type for China National Petroleum Corporation”.

（3）Third, in Figure 3 at Page 6, what does “Chang qing” mean?

Answer: Thank you for your feedback and for pointing out the issue with Figure 3. We have revised the figure legend for better clarity and accuracy. In Figure 3:

"Xinan" represents the Southwest Oil and Gas Field of China National Petroleum Corporation.
"Chang qing" represents the Changqing Oil and Gas Field of China National Petroleum Corporation.
"Tarim" represents the Tarim Oil and Gas Field of China National Petroleum Corporation.

This figure illustrates the annual production of natural gas by these three major subsidiaries of China National Petroleum Corporation. We have updated the legend accordingly to avoid any ambiguity.

Fig 3. China National Petroleum Corporation's Natural Gas Branch Annual Production Chart

Fourth, in Figure 3 at Page 7, there are five areas in the area chart, but only four types of natural gases listed in the figure.

Thank you for your suggestion. We apologize for this mistake and have corrected the original Figure 3, which is now Figure 4. In the revised Figure 4, there are four distinct areas representing the four types of natural gases.

Fig 4. Annual production chart of natural gas by type for China National Petroleum Corporation

Minor comments

（1）There are some typos in the current manuscript, including but not limited to:

Page 7, Line 285, “…methane production is 45.2%.In 2022…”.

Answer: Thanks for your suggestion. The mistake of line 285 has been corrected. This sentence has been revised as :“From this Figure, it can be seen that the average annual growth rate of CNPC's conven-tional gas production was 7.3% from 2000 to 2022, 26.7% for tight gas production from 2004 to 2022, 570% for shale gas production from 2012 to 2022, and 43.8% for coalbed methane production from 2009 to 2022.” An space after this sentence has been added.

Meanwhile, all typos and grammar mistakes have been checked and corrected in the new version of MS. Please see the revised MS for more detail.

Author Response File: Author Response.docx

Reviewer 4 Report

Comments and Suggestions for Authors

The presented research work provides a comprehensive overview on the current state of the China’s natural gas industry. The article is clear, well written and comfortable to read.

In my opinion, the manuscript is suitable for publication given that just a few minor issues are addressed, as listed here below:

- I suggest to consider changing the paper format from Article to Review. Since the manuscript outlines the current state of a given industrial sector, the Review format could be acceptable as well;

- Please make some Figure more readable. In particular, text in Figure one is very narrow and the two charts (Figure 5 and 6) contain a lot of text. Please consider modifying Figure 1 and readapting Figures 5 and 6;

- Please consider restructuring the sections in order to avoid subsubsubsections (e.g. (1) (2) etc.), except if strictly needed;

- Please adjust the Reference style (italics and bold) according to the guidelines provided by the Editor: Author 1, A.B.; Author 2, C.D. Title of the article. Abbreviated Journal Name Year, Volume, page range.

Author Response

Please see the attachment for detailed responses. Responses in the attachment is more comfortable to review.

Response for Reviewer 4:

Thank you for your detailed review and valuable suggestions. We have made the necessary revisions to address your comments and improve the manuscript.

Firstly, we changed the paper format from Article to Review as you suggested. Given that the manuscript outlines the current state of the natural gas industry and provides a comprehensive overview of its progress, challenges, and strategies, we agree that the Review format is more appropriate. This change allows us to present a more detailed synthesis of existing knowledge and highlight key areas for future research and industry practices.

Secondly, we made several improvements to the figures for better readability. Specifically, we standardized the size and font of all figures in the manuscript to ensure uniformity. For Figure 1, we rephrased the major events to highlight representative milestones and adjusted the formatting for clarity. For Figures 5 and 6, we condensed and refined the text within the images to make the key natural gas events for each basin clearer and more concise.

Thirdly, we restructured the sections to avoid subsubsubsections and improve readability. We merged the original Section 1.3.2 and Section 1.3.3 into a single section titled "Proven reserves and capacity of natural gas," discussing changes in proven reserves and production of shale gas in recent years. Additionally, in Sections 2.2.1 and 2.2.2, we deleted all subsubsubsections and expanded the subheadings into complete sentences to clearly state the main ideas. We also consolidated subsections in Section 2.3 for better coherence.

Lastly, we adjusted the reference style to comply with the guidelines provided by the Editor. The references now follow the correct format, ensuring consistency and clarity.

Point-by-Point Response to Reviewer

The presented research work provides a comprehensive overview on the current state of the China’s natural gas industry. The article is clear, well written and comfortable to read.

In my opinion, the manuscript is suitable for publication given that just a few minor issues are addressed, as listed here below:

（1） I suggest to consider changing the paper format from Article to Review. Since the manuscript outlines the current state of a given industrial sector, the Review format could be acceptable as well.

Answer: We appreciate the suggestion to consider changing the paper format from Article to Review. Given that the manuscript outlines the current state of the natural gas industry and provides a comprehensive overview of its progress, challenges, and strategies, we agree that the Review format is appropriate. Therefore, we have revised the manuscript accordingly to fit the Review format, ensuring that it provides a thorough and critical analysis of the relevant literature and developments in the field.

This change allows us to present a more detailed synthesis of existing knowledge and highlight the key areas of focus for future research and industry practices.

Answer: Thank you for your valuable suggestion. To ensure uniformity and neatness, we have standardized the size and font of all figures in the manuscript. The fonts and styles have been adjusted to maintain consistency throughout.

（1）We have made two key adjustments to the original Figure 1:

Major Events Rephrasing: We have rephrased the major events in the three development stages of the natural gas industry to highlight more representative milestones.
Formatting Adjustments: We have revised the formatting of the stage names and years to enhance clarity and emphasis on key points.

The modified Figure 1 is presented as follows:

Fig 1. Development stages of China's natural gas industry (Modified by [1]).

（2）For Figure 5 and Figure 6, we have significantly condensed and refined the text within the images to make the key natural gas events for each basin more clear and concise. The revised versions of Figure 5 and Figure 6 are presented below:

Fig 5. Major breakthroughs in conventional gas exploration in key basins of China in recent years.

Fig 6. Major breakthroughs and discoveries in unconventional gas fields: shale gas, deep coalbed methane, and tight gas exploration.

- Please consider restructuring the sections in order to avoid subsubsubsections (e.g. (1) (2) etc.), except if strictly needed;

Answer: We have restructured the sections to avoid subsubsubsections and improve readability. The following changes were made:

We merged the original Section 1.3.2 and Section 1.3.3 into Section 1.3.2, titled "Proven reserves and capacity of natural gas." This new section discusses the changes in the proven reserves and production of shale gas in China over recent years.
In Section 2.2.1 and Section 2.2.2, all subsubsubsections (e.g., (1), (2), etc.) have been deleted. Instead, we expanded these subheadings into complete sentences placed at the beginning of the respective paragraphs to clearly state the main idea. Please refer to the revised Section 2.2.1 and Section 2.2.2 in the manuscript.
The subsections in Section 2.3 have been significantly consolidated. The original Sections 2.3.3 and 2.3.5, which were specific examples of natural gas exploration in the Sichuan Basin, have been merged into Section 2.3.1. Please refer to Section 2.3.1 in the revised manuscript for these changes.

These adjustments aim to enhance the manuscript's structure, making it more coherent and easier to follow.

- Please adjust the Reference style (italics and bold) according to the guidelines provided by the Editor: Author 1, A.B.; Author 2, C.D. Title of the article. Abbreviated Journal Name Year, Volume, page range.

Answer: We have adjusted the reference style according to the guidelines provided by the Editor. Please see the list of references in the end of the revised MS for more details.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

All my comments have been addressed. Thank you!

Reviewer 3 Report

Comments and Suggestions for Authors

It is good to see that the authors have responded to all my previous comments. I do not have any other questions regarding the revised manuscript.

Article Menu

Progress, Challenges, and Strategies for China’s Natural Gas Industry Under Carbon-Neutrality Goals

Further Information

Guidelines

MDPI Initiatives

Follow MDPI