학술논문

Pre- and post-production processes increasingly dominate greenhouse gas emissions from agri-food systems
Document Type
Academic Journal
Source
Earth System Science Data. April 14, 2022, Vol. 14 Issue 4, p1795.
Subject
Nitrogen oxide
Methane
Greenhouse gases
Agricultural land
Video post production
Refuse and refuse disposal
Food supply
Air pollution
Language
English
ISSN
1866-3508
Abstract
We present results from the FAOSTAT emissions shares database, covering emissions from agri-food systems and their shares to total anthropogenic emissions for 196 countries and 40 territories for the period 1990-2019. We find that in 2019, global agri-food system emissions were 16.5 (95 %; CI range: 11-22) billion metric tonnes (Gt CO.sub.2 eq. yr.sup.-1 ), corresponding to 31 % (range: 19 %-43 %) of total anthropogenic emissions. Of the agri-food system total, global emissions within the farm gate - from crop and livestock production processes including on-farm energy use - were 7.2 Gt CO.sub.2 eq. yr.sup.-1 ; emissions from land use change, due to deforestation and peatland degradation, were 3.5 Gt CO.sub.2 eq. yr.sup.-1 ; and emissions from pre- and post-production processes - manufacturing of fertilizers, food processing, packaging, transport, retail, household consumption and food waste disposal - were 5.8 Gt CO.sub.2 eq. yr.sup.-1 . Over the study period 1990-2019, agri-food system emissions increased in total by 17 %, largely driven by a doubling of emissions from pre- and post-production processes. Conversely, the FAOSTAT data show that since 1990 land use emissions decreased by 25 %, while emissions within the farm gate increased 9 %. In 2019, in terms of individual greenhouse gases (GHGs), pre- and post-production processes emitted the most CO.sub.2 (3.9 Gt CO.sub.2 yr.sup.-1 ), preceding land use change (3.3 Gt CO.sub.2 yr.sup.-1) and farm gate (1.2 Gt CO.sub.2 yr.sup.-1) emissions. Conversely, farm gate activities were by far the major emitter of methane (140 Mt CH.sub.4 yr.sup.-1) and of nitrous oxide (7.8 Mt N.sub.2 O yr.sup.-1). Pre- and post-production processes were also significant emitters of methane (49 Mt CH.sub.4 yr.sup.-1 ), mostly generated from the decay of solid food waste in landfills and open dumps. One key trend over the 30-year period since 1990 highlighted by our analysis is the increasingly important role of food-related emissions generated outside of agricultural land, in pre- and post-production processes along the agri-food system, at global, regional and national scales. In fact, our data show that by 2019, pre- and post-production processes had overtaken farm gate processes to become the largest GHG component of agri-food system emissions in Annex I parties (2.2 Gt CO.sub.2 eq. yr.sup.-1). They also more than doubled in non-Annex I parties (to 3.5 Gt CO.sub.2 eq. yr.sup.-1 ), becoming larger than emissions from land use change. By 2019 food supply chains had become the largest agri-food system component in China (1100 Mt CO.sub.2 eq. yr.sup.-1 ), the USA (700 Mt CO.sub.2 eq. yr.sup.-1) and the EU-27 (600 Mt CO.sub.2 eq. yr.sup.-1). This has important repercussions for food-relevant national mitigation strategies, considering that until recently these have focused mainly on reductions of non-CO.sub.2 gases within the farm gate and on CO.sub.2 mitigation from land use change. The information used in this work is available as open data with DOI https://doi.org/10.5281/zenodo.5615082 (Tubiello et al., 2021d). It is also available to users via the FAOSTAT database (https://www.fao.org/faostat/en/#data/EM; FAO, 2021a), with annual updates.
Byline: Francesco N. Tubiello, Kevin Karl, Alessandro Flammini, Johannes Gütschow, Griffiths Obli-Laryea, Giulia Conchedda, Xueyao Pan, Sally Yue Qi, Hörn Halldórudóttir Heiðarsdóttir, Nathan Wanner, Roberta Quadrelli, Leonardo Rocha Souza, Philippe [...]