The GHG Protein Ratio: An Indicator Whose Time Has Come

The Carbon Footprint (CF) of agriculture must be substantially reduced to help avoid catastrophic climate change. This paper examines the ratio of Greenhouse Gas (GHG) emissions to protein as an indicator of the CF of the major Canadian livestock commodities using previously published results. The GHG emissions for these commodities were estimated with a spreadsheet model that accounted for all three GHGs, the complete life cycles of each livestock type and the livestock interactions with the agricultural land base. The indicator results reviewed here included the responses to livestock types and diets, livestock versus plant protein sources, spatial scales and geographic differences. The sensitivity of the results shown suggest that GHG-protein ratios could provide valuable guidance for producers and consumers to reduce their GHG emissions. For example, diverting feed grains from beef feedlots to hog production would substantially reduce the CF of red meat, although still not as low as the CF of poultry products. The complete proteins derived from pulses have much lower CF values than all livestock products.