Greenhouse Gas Emissions and Mitigation Strategies in Universities Under ISO 14064-1: Lessons for Global Higher Education Sustainability

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Please see the attachment.

Comments for author File: Comments.pdf

Author Response

Comment 1:

The authors studied greenhouse gas (GHG) emissions in Higher Education Institutes (HEIs), using the ISO 14064-1:2018 framework. They found that the purchased electricity constitutes the dominant share of emissions, while fugitive refrigerant leakage, commuting and business travel represent substantial components of the institutional carbon footprint. They also revealed the sensitivity of GHG inventories to both policy and behavioural changes. They proposed a framework integrating ISO 14064-1 compliance with data quality assurance and digital verification tools. The framework should be helpful to HEIs in their efforts to achieve carbon neutrality. The publication is recommended.

Response:

We sincerely thank the reviewer for the supportive comments and positive evaluation of our manuscript. We are pleased that the proposed ISO 14064-1–based framework and its application to fugitive emissions, Scope 3 activities, and data governance were found to be relevant and replicable for the higher education sector. We have carefully preserved the original structure and clarity of the study as submitted.

Comment 2:

The authors are encouraged to explore the applicability of their findings in institutions outside the HEI.

Response:

Thank you for this valuable suggestion. In the revised manuscript (Discussion section, lines 430–449), we have added a paragraph outlining how the proposed framework could be adapted for use in other public institutions, such as hospitals, research centers, and government campuses. We discuss similarities in operational structures, emissions categories (e.g., refrigerants, commuting), and data challenges, which support the model’s broader applicability. A brief comparison with GHG reporting practices in municipal governments and healthcare systems has also been added with relevant citations.

Reviewer 2 Report

Comments and Suggestions for Authors

Please see the attachment.

Comments for author File: Comments.pdf

Author Response

1) Enrich literature review; clarify necessity & novelty.

Response:

Thank you. We expanded the Introduction to synthesize recent advances and gaps in (i) Scope 3 accounting, (ii) refrigerant (fugitive) emissions, and (iii) data governance in HEIs, and we now state three distinct contributions: (1) the first Taiwan-based, multi-year (2021–2024) ISO 14064-1:2018–compliant university inventory; (2) quantified sensitivity of totals and mitigation ranking to both emission-factor revisions and activity-data corrections (commuting/business travel); (3) a replicable governance-and-verification pipeline (materiality ≥3%, Monte-Carlo uncertainty propagation, third-party checkpoints) transferable beyond HEIs.

Manuscript change. Two new paragraphs have been added to the end of the Introduction; references have been broadened beyond JCP (Energy Policy, EIA Review, Sustainability, Nature Climate Change, ERL).

2) Add a chapter outline at the end of the Introduction.

Response:

Added a concise article roadmap as the final paragraph of the Introduction.

Manuscript change (exact text).

“The remainder of this paper is structured as follows: Section 2 details the ISO 14064-1–aligned research design, boundary definition, data governance, and uncertainty/materiality assessment. Section 3 reports multi-year results, factor-change sensitivity, and category-level drivers. Section 4 discusses transferability and managerial implications. Section 5 concludes with limitations and future research.”

3) Add a paragraph outlining structure (merged with #2).

Response:

Addressed alongside Point #2 to avoid redundancy, a single outline paragraph closes the Introduction.

4) Justify starting in 2021 (vs. 2019–2024).

Response:

We clarified that 2019–2020 were transition years (pandemic shock; partial ISO adoption). As of 2021, the ISO 14064-1 operational control boundary, category taxonomy, materiality rule, and third-party verification gates were fully established. Scope 3 key classes (commuting/travel) were introduced from 2022, using consistent methods. 2021 marks an early stage of post-pandemic normalization, enabling comparability.

Manuscript change. One paragraph has been added in Methods §2.1, “Framework and boundary,” explaining the period selection.

5) Add 2021 data to Figures 1 and 4.

Response:

Done. Figure 1 (Scopes) now spans 2021–2024; Figure 4 (refrigerants) now spans 2021–2024 with equipment counts and per-unit averages; shaded band marks the 2023→2024 factor revision.

Manuscript change (caption updates).

Figure 1. “Annual GHG emissions by scope, 2021–2024. 2021 baseline included; error bars = 95% CIs (10,000-run Monte Carlo).”

Figure 4. “Refrigerant fugitive emissions, unit counts, and per-unit averages, 2021–2024. Shaded band = 2023→2024 factor revision; error bars = 95% CIs.”

6) Demonstrate scientific validity beyond descriptive statistics.

Response:

We added formal inference and uncertainty methods: Mann–Kendall trend tests (α=0.05) with Theil–Sen slopes; 10,000-run Monte-Carlo uncertainty propagation combining activity-data variance and factor ranges (95% CIs at category/total levels); one- and two-way sensitivity tests for refrigerant (±10%) and LPG (−5%) factors; bootstrap CIs for mean differences; stratified weighting for commuting surveys.

Manuscript change. New subsection “§2.x Statistical and Uncertainty Procedures”; Results augmented with p-values/CIs where relevant.

7) Add future research prospects in the Conclusion.

Response:

Added a “Future work” paragraph covering: department-level MACCs; digital MRV (IoT metering, refrigerant tracking); boundary expansion toward procurement-driven Scope 3 and site-level LCA; and policy scenario testing (renewable grid share, f-gas regulation, carbon pricing/CBAM).

Manuscript change. Final paragraph in Conclusion labeled “Future work.”

8)Broaden literature beyond Journal of Cleaner Production.

 

Response

 

Thank you for this helpful suggestion. We revised the manuscript to broaden the literature base by incorporating references from Energy Policy, Environmental Impact Assessment Review, Sustainability, Nature Climate Change, Environmental Research Letters, and national factor guidelines in addition to the GHG Protocol. These citations strengthen the international relevance of the study and balance the reference list beyond JCP.

Manuscript Changes

Introduction (lines 52–64, 108–116): Added references to recent policy-driven literature (Nature Climate Change, Energy Policy) and methodological debates (EIA Review, ERL).

Methods Section 2.1–2.4 (lines 128–185, 194–212): Added national emission factor guidelines (EPA Taiwan, 2024) and the GHG Protocol to emphasize methodological comparability across jurisdictions.

References (lines 476–523): Expanded and renumbered accordingly to include the above works.

Reviewer 3 Report

Comments and Suggestions for Authors

This research offers a three-year analysis of greenhouse gas emissions at a university, guided by the ISO 14064-1:2018 framework. It identifies purchased electricity as the main emission source, while highlighting overlooked contributors like refrigerant leaks and Scope 3 activities (commuting, business travel). Methodological improvements—such as updated emission factors and better data verification—show how sensitive emissions data is to policy and behavior changes. The study demonstrates that targeted actions like refrigerant control and low-carbon transport can reduce emissions even as campus activity grows. Importantly, it introduces a replicable model for higher education institutions to improve reporting accuracy and accelerate their path to carbon neutrality, positioning universities as key players in global climate leadership.

This study is accurate and effective in identifying key contributors to GHG emissions in a university context. It offers a helpful and detailed model for other universities to implement. It usefully synthesizes prior research in this field, and its findings are relevant and actionable for other universities throughout the world today, especially those universities that are required by their local and national government policy frameworks to track and reduce their GHG emissions.

However, GHG emission tracking and reduction strategies are a well-established field of study, and it is unclear in what specific respects this study makes an original contribution to its field of research. For this reason, I have rated its originality and contribution to scholarship as "average." This study could be improved by making clear in what respect(s) its findings represent an original contribution to its field of scholarship, rather than constituting simply an application or refinement of existing knowledge and techniques of measurement and analysis.

Author Response

1. This research offers a three-year analysis of greenhouse gas emissions at a university, guided by the ISO 14064-1:2018 framework. It identifies purchased electricity as the main emission source, while highlighting overlooked contributors like refrigerant leaks and Scope 3 activities (commuting, business travel). Methodological improvements—such as updated emission factors and better data verification—show how sensitive emissions data is to policy and behavior changes. The study demonstrates that targeted actions like refrigerant control and low-carbon transport can reduce emissions even as campus activity grows. Importantly, it introduces a replicable model for higher education institutions to improve reporting accuracy and accelerate their path to carbon neutrality, positioning universities as key players in global climate leadership.

Response:

We sincerely thank the reviewer for providing an accurate summary and a positive assessment of our study’s scope and methodological rigor. We appreciate your recognition of the study’s contributions in identifying overlooked emission categories, implementing methodological improvements, and offering a replicable model aligned with ISO 14064-1 for the higher education sector.

2. This study is accurate and effective in identifying key contributors to GHG emissions in a university context. It offers a helpful and detailed model for other universities to implement. It usefully synthesizes prior research in this field, and its findings are relevant and actionable for other universities throughout the world today, especially those universities that are required by their local and national government policy frameworks to track and reduce their GHG emissions.

Response:

Thank you for acknowledging the robustness of our GHG inventory model and its practical applicability to other universities, particularly in light of evolving regulatory pressures. We are pleased that the synthesis of prior research and actionable insights was found to be both relevant and helpful by the reviewer.

3. However, GHG emission tracking and reduction strategies are a well-established field of study, and it is unclear in what specific respects this study makes an original contribution to its field of research. For this reason, I have rated its originality and contribution to scholarship as "average." This study could be improved by making clear in what respect(s) its findings represent an original contribution to its field of scholarship, rather than constituting simply an application or refinement of existing knowledge and techniques of measurement and analysis.

Response:

We appreciate this constructive suggestion and have revised the manuscript to clarify its original contributions. Specifically, this study is the first known multi-year ISO 14064-1–compliant GHG inventory in a Taiwanese university context, incorporating updated Scope 3 commuting and fugitive refrigerant data post-pandemic. Additionally, we introduce a replicable data governance mechanism and demonstrate how revisions to emission factors materially influence reported values and mitigation prioritization. These methodological innovations—combined with digital validation processes and integration with national inventory reforms—extend beyond typical application studies and contribute novel insights into institutional carbon accountability. Clarifications have been made in the Introduction, Discussion, and Conclusion sections accordingly.

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

1. The words of “three-years” in the Introduction can clarify the timeframe.
2. Figures 1 and 4 should display the 2021 baseline data, which is currently not shown.
3. The Conclusion section can be divided into two paragraphs, with future research directions in a separate paragraph.
4. To avoid ambiguity for readers, please refer to “Taiwan” throughout the text as “Taiwan, China.”
5. Please prepare a point-by-point response PDF file when addressing the feedback.

Author Response

Reviewer 2: The English could be improved to more clearly express the research.

Response: We sincerely thank the reviewer for this observation. We fully agree that clarity of expression is essential for effective scholarly communication. In preparing the revised manuscript, we have carefully rechecked the language throughout, focusing on grammar, readability, and precision of terminology. Minor refinements were made to improve fluency further and ensure that the arguments are presented as clearly as possible. We genuinely appreciate this reminder and believe that the current version now better reflects the intended contributions of our study.

Round 3

Reviewer 2 Report

Comments and Suggestions for Authors

The author did not reply to my suggestion.

Author Response

The English could be improved to more clearly express the research.

Response:

We sincerely thank the reviewer for this continued and helpful observation. We fully agree that clear, precise language is essential for effective scientific communication.

To address this, our team has:

• conducted a line-by-line editorial review to correct typos, streamline phrasing, and improve sentence flow;
• applied targeted grammar and style refinements (e.g., removing redundancies, tightening topic sentences, standardizing terminology);
• performed a full cross-check of references and in-text citations (correcting numbering, completing DOIs, and aligning citation style);
• engaged a professional scientific editor to conduct final revisions aimed at improving clarity, readability, and consistency.

If any specific sentences or sections remain unclear, we would appreciate targeted pointers (page/line numbers) to revise them immediately and precisely. We understand the reviewer’s time and constructive input, and we hope the current revision now meets the journal’s standards for clarity and presentation.