Blog: Reporting how livestock contribute to global warming
This blog post by John Lynch of the Oxford Livestock, Environment and People programme explains how GWP* can be used to describe the warming effect of both short- and long-lived greenhouse gases, particularly when applied to livestock.
Using GWP* (as opposed to GWP100), stable levels of methane emissions are reported as causing warming equivalent to a fairly small pulse of carbon dioxide. Increasing methane emissions slightly would cause warming equivalent to a large pulse of carbon dioxide emissions, while decreasing methane emissions slightly would cause a decrease in warming, equivalent to removing carbon dioxide from the atmosphere.
Read the full piece here. See also the paper Demonstrating GWP*: a means of reporting warming-equivalent emissions that captures the contrasting impacts of short- and long-lived climate pollutants on which the blog is based, and the Foodsource building block Agricultural methane and its role as a greenhouse gas.
While some of the food system challenges facing humanity are local, in an interconnected world, adopting a global perspective is essential. Many environmental issues, such as climate change, need supranational commitments and action to be addressed effectively. Due to ever increasing global trade flows, prices of commodities are connected through space; a drought in Romania may thus increase the price of wheat in Zimbabwe.