The carbon footprint of coffee refers to the sum of greenhouse gas emissions and removals through its entire lifecycle and their contribution to climate change − from the coffee farm all the way to consumption and end-of-life.
Carbon dioxide tends to be the main greenhouse gas contributor known by the general public. However, the sum of emissions also includes other gases produced not only in the agricultural process, but also those produced in industrial activities such as methane and nitrous oxide - whose global warming potential is higher than CO21,2.
It is estimated that modern food systems account for almost 18 billion tonnes of greenhouse gas emissions, a third of the world’s total emissions3. As with any product, coffee’s emissions can be measured at different points in its lifecycle with ongoing efforts by coffee companies to reduce these within their value chain wherever possible4. Through a combination of changing coffee farming techniques, transportation, and consumption methods, up to 77% of coffee’s current emissions could be reduced5.
ISIC’s specific focus is on the accurate measurement of emissions related to green coffee – covering the farming, harvest, and post-harvest processing phases. It is estimated that these phases of coffee’s lifecycle account for over half of the commodity’s total emissions6.
Despite existing international standards and measurements7,8,9, what has proven difficult to date is setting a clear sector-wide methodology to measure green coffee’s carbon footprint and wider greenhouse gas emissions. This would include accounting for and modelling the varying emissions created as a result of fertilizer use, residue management, irrigation, wastewater treatment, and removals achieved through agricultural practices used across thousands of coffee producers worldwide.
A huge amount of work to date has however gone in to understanding the varying carbon footprint of green coffee growing and post-harvesting processes10,11,12. Data on green coffee’s carbon footprint lifecycle, including outside of the cultivation and initial processing stages, has traditionally not always been readily available, robust, or representative enough of the world’s vastly varying coffee-growing regions and farming systems. This challenge is not necessarily unique to coffee, and lifecycle assessments can always be refined and improved.
As with any plant, coffee trees absorb carbon and produce oxygen as they grow. Coffee is traditionally a crop which does not require significant land till or disturbance, such as ploughing, as part of its farming. Land till releases stored carbon into the atmosphere so, compared to other crops, coffee farming systems are able to compensate some of their emissions by removing carbon13. This potential grows when intercropping and shade grown coffee techniques are also employed14.
ISIC seeks to contribute to better understand whether, when grown and managed appropriately for local conditions, coffee can in fact become a restorative source for the planet. The use of intercropping15, shade-grown16, and agroforestry17 techniques have all shown potential to mitigate possible climate effects caused by green coffee’s carbon footprint. This includes the potential to increase soil organic carbon stocks – the amount of carbon absorbed and stored in the soil coffee is grown in. However, assessing the potential for increasing soil carbon stock needs more work, particularly to ensure consistent and representative measurement.
Further research and schemes are also needed across the board to clearly monitor, report, and verify the benefits of possible mitigation techniques in the long-term – particularly if they are to be applied at scale.
