A model for estimating carbon accumulation in cork products

Aim of study: This study aims to develop a calculation model for estimating carbon accumulation in cork products, both whilst in use and when in landfills, and to apply the model to Portugal as an example. Area of study: The model is applicable worldwide and the case-study is Portugal. Material and methods: The model adopts a flux-data method based on a lifetime analysis and quantifies carbon accumulation in cork products according to three approaches that differ on how carbon stocks (or emissions) are allocated to cork product consuming and producing countries. These approaches are: stock-change, production and atmospheric-flow. The effect on carbon balance of methane emissions from the decay of cork products in landfills is also evaluated. Main results: The model was applied to Portugal and the results show that carbon accumulation in cork products in the period between 1990 and 2010 varied between 24 and 92 Gg C year(-1). The atmospheric-flow approach provided the highest carbon accumulation over the whole period due to the net export of carbon in cork products. The production approach ranked second because exported cork products were mainly manufactured from domestically produced cork. The net carbon balance in cork products was also a net carbon accumulation with all the approaches, ranging from 5 to 81 Gg C-eq year(-1). Research highlights: The developed model can be applied to other countries and may be a step forward to consider carbon accumulation in cork products in national greenhouse gas inventories, as well as in future climate agreements.