Showing results for: Carbon footprinting
The carbon footprint is a consumption-based indicator used to highlight the climate impacts of a certain good or service. Carbon footprinting is based on the life cycle assessment (LCA) approach but focuses only on greenhouse gas emissions, rather than a suite of environmental areas. The “size” of the footprint is usually expressed in terms of carbon dioxide equivalent (CO2e). The footprint analysis considers impacts along several or all the stages of a product’s life cycle, which may span agricultural production (and the inputs to this production) through to consumption and waste disposal. The footprint approach can be used to measure the carbon impact of food at various scales; from the individual food product, to an entire meal, through to a dietary pattern of an individual or a country. Carbon footprinting may simply be undertaken by a company in order to understand the impacts of the products it sells and ascertain opportunities for improvement, but information about a product's footprint is also occasionally included on packaging in the form of a consumer-oriented label.
This report from the international non-profit Institute for Agriculture and Trade Policy examines the climate impacts of large dairy corporations. It finds that greenhouse gas emissions from the 13 largest dairy companies have increased by 11% over the last two years, alongside an 8% increase in milk production, and that none of these corporations has published plans to cut total emissions in their dairy supply chains.
This working paper from the World Resources Institute compares the carbon footprint of dairy from 13 different countries and pork from 11 countries. It uses a carbon opportunity cost approach to carbon footprinting, i.e. it accounts for carbon that is not stored in vegetation or soils because the land is being used to produce dairy or pork.
FCRN member Erasmus zu Ermgassen has co-authored this paper, which calculates variations in the carbon footprint of soy products grown in different regions of Brazil. It finds that soy from certain areas associated with loss of natural vegetation has a carbon footprint per unit of product six times higher than the average carbon footprint of Brazilian soy. It also finds that soy products imported by the European Union are more likely to be from regions linked to deforestation than soy exported from Brazil to other places, such as China.
This blog post by John Lynch of the Oxford Livestock, Environment and People programme explains how GWP* can be used to describe the warming effect of both short- and long-lived greenhouse gases, particularly when applied to livestock.
This paper uses several simple emissions scenarios to illustrate how GWP* (as opposed to GWP100) can report the warming created by both short-lived greenhouse gases such as methane (CH4) and long-lived greenhouse gases such as carbon dioxide (CO2).
This book by Sarah Bridle provides an accessible outline of the links between climate change and food: both the climate impacts of producing food, and the impacts of climate change on farming.
Our World in Data has published this piece, which breaks down the extent to which the differences in carbon footprints of food categories can be attributed to methane, a short-lived greenhouse gas which has attracted controversy over how its climate impact is measured.
FCRN member Christian Reynolds has co-authored this paper, which finds that in Japan, differences in the carbon footprint of household food consumption are driven by what the paper describes as “unexpected” food categories: the households with higher food carbon footprints spend more on restaurant food, fish, vegetables, alcohol and confectionary.
This briefing from the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS) notes that demand for five cereals in sub-Saharan Africa is set to almost triple by 2050. It argues that it is possible for the region to be self-sufficient in cereals by 2050 using only the current area of cereal farmland, but that this requires significantly higher fertiliser use. To keep greenhouse gas emissions to the minimum possible will require suitable crop varieties, careful nutrient management, optimum planting densities and protection of crops against weeds, pests and diseases.
The Greenhouse Gas and Dietary choices Open source Toolkit (GGDOT) project funded by N8 Agrifood has launched two games about for public engagement on food and climate. The Climate Food Challenge is a single-player online game while the climate food flashcards can be printed off for two players to use. Both involve comparing the carbon footprint of different food types.
FCRN members Laurence Smith and Adrian Williams co-authored this paper, which finds that converting all food production in England and Wales to organic farming would reduce direct agricultural emissions in the UK, but would cause higher emissions from overseas farming due to lower yields in England and Wales.
Michelle Cain, Myles Allen and John Lynch of the University of Oxford have published a plain-language briefing note that explains how different ways of measuring the climate impact of methane (GWP100 versus GWP*) affect definitions of net zero emissions targets.
Methane emissions from ammonia fertiliser manufacturing plants (which use natural gas as a feedstock and energy source) in the United States are around one hundred times higher than currently reported levels, according to this study. Researchers used a Google Street View car equipped with methane analysers to take measurements downwind of six ammonia fertiliser plants (there are only 23 such plants in the US).
This paper by FCRN member Elinor Hallström assesses the nutritional content and climate impact of 37 seafood products. The paper finds high variability in nutritional and climate performance, with no consistent correlation between nutrition and climate impact across different seafood species. The paper calls for dietary advice to promote species with low climate impact and high nutritional value, including sprat, herring, mackerel and perch.
The UK’s Food and Drink Federation (FDF) has published its 2018 environmental progress report. FDF members report a 53% reduction in their greenhouse gas emissions from energy use in manufacturing operations since 1990, and a 39% reduction in water consumption since 2008.
This paper, by John Lynch of the University of Oxford’s LEAP project, finds that carbon footprint studies of beef cattle typically do not report separate values for emissions of different greenhouse gases such as methane and nitrous oxide. Instead, studies generally report only an aggregated figure in the form of the 100-year Global Warming Potential (GWP100) as CO2-equivalent.
This paper, by researchers from the University of Oxford’s LEAP project, models the climate impacts of beef cattle and cultured meat over the next 1000 years using a climate model that treats carbon dioxide, methane and nitrous oxide separately, instead of using the widespread Global Warming Potential, which assigns a CO2-equivalent value to each greenhouse gas according to warming caused over a specified timeframe.