Application of an expanded sequestration estimate to the domestic energy footprint of the Republic of Ireland

Abstract

The need for global comparability has led to the recent standardization of ecological footprint methods. The use of global averages and necessary methodological assumptions has questioned the ability of the ecological footprint to represent local or national specific concerns. This paper attempts to incorporate greater national relevancy by expanding the sequestration estimate used to calculate the annual carbon footprint of domestic Irish energy use. This includes expanding existing study boundaries to include additional carbon pools such as the litter, dead and soil pools. This generated an overall estimate of 4.38 tonnes of carbon per hectare per year (t C/ha/yr), resulting in an ecological footprint estimate of 0.49 hectares per capita (ha/cap) The method employed in this paper also incorporated the potential role of grassland as a carbon sink. The caveat that the resultant value is dependent on the choice of study boundary is discussed. Including the lateral movement of carbon embodied in farm products (effectively placing the boundary around the farm gate) reduces the estimate of grassland carbon sequestration by approximately 44% to 1.82 t C/ha/yr. When a footprint calculated using an overall sequestration estimate (based on the distribution of Irish grassland and forestry) is translated into global hectares (gha), the standardized value is reduced by 35%.