Enteric methane emission factors of smallholder dairy farming systems across intensification gradients in the central highlands of Ethiopia.

Background: Following global pledges to reduce greenhouse gas (GHG) emissions by 30% by 2030 compared to the baseline level of 2020, improved quantification of GHG emissions from developing countries has become crucial. However, national GHG inventories in most Sub-Saharan African countries use default (Tier I) emission factors (EF) generated by the Intergovernmental Panel on Climate Change (IPCC) to estimate enteric CH emissions from animal agriculture. The present study provides an improved enteric CH emission estimate (Tier II) based on animal energy requirements derived from animal characteristics and performance data collected from about 2500 cattle in 480 households from three smallholder farming systems to represent the common dairy farming in the central highlands of Ethiopia.