Location: Livestock Nutrient Management Research
Title: Enteric methane emissions: where we currently stand, why we should care, and future mitigation scenarios?Author
Beck, Matthew | |
THOMPSON, LOGAN - Kansas State University |
Submitted to: Beef Magazine
Publication Type: Trade Journal Publication Acceptance Date: 7/10/2023 Publication Date: 8/1/2023 Citation: Beck, M.R., Thompson, L.R. 2023. Enteric methane emissions: where we currently stand, why we should care, and future mitigation scenarios?. Beef Magazine. July/August. Article 6. Interpretive Summary: Technical Abstract: Enteric methane is the largest source of total U.S. methane emissions, composing 26%. Greenhouse gas reporting and accounting agencies relate warming potential of different greenhouse gases to an equivalence basis. This is commonly achieved by both national (U.S. Environmental Protection Agency; EPA) and international (Intergovernmental Panel on Climate Change; IPCC) reporting bodies by multiplying a given gas' emission rate (mass per year) by its global warming potential on a 100-year basis (GWP100). The GWP100 value of methane is 28. Ever since the GWP100 method has become international convention, its appropriateness has been debated. This is because methane has a short atmospheric lifespan of 12 years. This means that in periods where methane emission rates are decreasing, then there would be less methane in the atmosphere to trap heat. As a result, the GWP100 method has been shown to not relate well to actual climate warming. In order to account for the nuanced atmospheric behavior of short-lived greenhouse gases, like methane, a relatively new method has been developed. This method is termed global warming potential-star (GWP*). This method relates emission rates to those 20 years prior and has been shown to relate well with modeled climate warming. This article relates the contribution of enteric methane from the beef industry to highlight its contribution to U.S. derived implied climate change when looking through the GWP100 and GWP* lens. We further break this contribution down by beef industry sector. Next we discuss the economic road-block to adopting certain mitigation strategies and potential opportunities to overcome this hurdle. Finally, this article runs through four future scenarios to highlight the importance of reducing enteric methane from pasture based systems. |