Methodologies for quantifying greenhouse gas emissions in food systems: A comprehensive review

Accurately quantifying greenhouse gas (GHG) emissions within food systems is critical for informing climate policies and advancing sustainable food transitions. Compared to traditional sectoral approaches, a food system approach can offer a more quantitatively holistic approach to capture emissions....

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Main Authors: Ngaiwi, Mary Eyeniyeh, Vanegas, Martha, Sylvester, Janelle M., Verchot, Louis, Castro Nunez, Augusto Carlos
Format: Journal Article
Language:Inglés
Published: IOP Publishing 2025
Subjects:
Online Access:https://hdl.handle.net/10568/176939
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author Ngaiwi, Mary Eyeniyeh
Vanegas, Martha
Sylvester, Janelle M.
Verchot, Louis
Castro Nunez, Augusto Carlos
author_browse Castro Nunez, Augusto Carlos
Ngaiwi, Mary Eyeniyeh
Sylvester, Janelle M.
Vanegas, Martha
Verchot, Louis
author_facet Ngaiwi, Mary Eyeniyeh
Vanegas, Martha
Sylvester, Janelle M.
Verchot, Louis
Castro Nunez, Augusto Carlos
author_sort Ngaiwi, Mary Eyeniyeh
collection Repository of Agricultural Research Outputs (CGSpace)
description Accurately quantifying greenhouse gas (GHG) emissions within food systems is critical for informing climate policies and advancing sustainable food transitions. Compared to traditional sectoral approaches, a food system approach can offer a more quantitatively holistic approach to capture emissions. This literature review synthesizes methodological approaches and boundary considerations in food system GHG accounting. It uses a structured narrative synthesis to categorize and compare emissions quantification across jurisdictional, product-specific, consumer-driven, and trade-related boundaries, as well as across the different food system stages, including agricultural production, processing, distribution, retail, consumption, and waste management, highlighting how these choices shape policy relevance and outcomes. While life cycle assessment (LCA) remains the dominant method, complementary approaches, including direct measurements, process-based models, and hybrid frameworks, are increasingly used to address limitations in coverage, spatial and temporal resolution, and system feedback. The results show that reported emissions vary widely, up to twofold in some cases, even under nominally similar system boundaries, due to differences in boundary scope, methodological approach (e.g. Tier-1 vs Tier-2 factors; inventories vs LCA), and underlying data sources (e.g. FAOSTAT vs EDGAR). This variation highlights the need for boundary-aware comparisons and supports the use of hybrid frameworks that combine complementary methods to improve coverage, resolution, and consistency. Additionally, integrating sectors across production, consumption, and waste, food system approaches may help identify high-leverage, cost-effective mitigation opportunities that are often obscured in sector-based reporting. Rather than identifying a single best method, the review underscores the importance of matching methods to boundary scope, data context, and decision-making needs, highlighting the value of integrated, food system-wide perspectives for improving consistency and informing targeted mitigation strategies.
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spelling CGSpace1769392025-11-11T19:00:41Z Methodologies for quantifying greenhouse gas emissions in food systems: A comprehensive review Ngaiwi, Mary Eyeniyeh Vanegas, Martha Sylvester, Janelle M. Verchot, Louis Castro Nunez, Augusto Carlos food systems greenhouse gas emissions assessment desarrollo bajo en emisiones sistema alimentario life cycle emisión de gases de efecto invernadero Accurately quantifying greenhouse gas (GHG) emissions within food systems is critical for informing climate policies and advancing sustainable food transitions. Compared to traditional sectoral approaches, a food system approach can offer a more quantitatively holistic approach to capture emissions. This literature review synthesizes methodological approaches and boundary considerations in food system GHG accounting. It uses a structured narrative synthesis to categorize and compare emissions quantification across jurisdictional, product-specific, consumer-driven, and trade-related boundaries, as well as across the different food system stages, including agricultural production, processing, distribution, retail, consumption, and waste management, highlighting how these choices shape policy relevance and outcomes. While life cycle assessment (LCA) remains the dominant method, complementary approaches, including direct measurements, process-based models, and hybrid frameworks, are increasingly used to address limitations in coverage, spatial and temporal resolution, and system feedback. The results show that reported emissions vary widely, up to twofold in some cases, even under nominally similar system boundaries, due to differences in boundary scope, methodological approach (e.g. Tier-1 vs Tier-2 factors; inventories vs LCA), and underlying data sources (e.g. FAOSTAT vs EDGAR). This variation highlights the need for boundary-aware comparisons and supports the use of hybrid frameworks that combine complementary methods to improve coverage, resolution, and consistency. Additionally, integrating sectors across production, consumption, and waste, food system approaches may help identify high-leverage, cost-effective mitigation opportunities that are often obscured in sector-based reporting. Rather than identifying a single best method, the review underscores the importance of matching methods to boundary scope, data context, and decision-making needs, highlighting the value of integrated, food system-wide perspectives for improving consistency and informing targeted mitigation strategies. 2025-12-01 2025-10-09T13:27:35Z 2025-10-09T13:27:35Z Journal Article https://hdl.handle.net/10568/176939 en Open Access application/pdf IOP Publishing Ngaiwi, M.E.; Vanegas, M.; Sylvester, J.M.; Verchot, L.; Castro Nunez, A.C. (2025) Methodologies for quantifying greenhouse gas emissions in food systems: A comprehensive review. Environmental Research: Food Systems, 2: 042001. ISSN: 2976-601X
spellingShingle food systems
greenhouse gas emissions
assessment
desarrollo bajo en emisiones
sistema alimentario
life cycle
emisión de gases de efecto invernadero
Ngaiwi, Mary Eyeniyeh
Vanegas, Martha
Sylvester, Janelle M.
Verchot, Louis
Castro Nunez, Augusto Carlos
Methodologies for quantifying greenhouse gas emissions in food systems: A comprehensive review
title Methodologies for quantifying greenhouse gas emissions in food systems: A comprehensive review
title_full Methodologies for quantifying greenhouse gas emissions in food systems: A comprehensive review
title_fullStr Methodologies for quantifying greenhouse gas emissions in food systems: A comprehensive review
title_full_unstemmed Methodologies for quantifying greenhouse gas emissions in food systems: A comprehensive review
title_short Methodologies for quantifying greenhouse gas emissions in food systems: A comprehensive review
title_sort methodologies for quantifying greenhouse gas emissions in food systems a comprehensive review
topic food systems
greenhouse gas emissions
assessment
desarrollo bajo en emisiones
sistema alimentario
life cycle
emisión de gases de efecto invernadero
url https://hdl.handle.net/10568/176939
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