Neglected Transformational Responses: Implications Of Excluding Short Lived Emissions And Near Term Projections In Greenhouse Gas Accounting

Abstract

Greenhouse gas conventions and metrics have powerful framing effects, significantly under-reporting emissions and obscuring the impact of shorter-lived emissions. This interdisciplinary Australian case study re-calculates emissions to include short lived gases and use 20 year Global Warming Potentials (GWPs), a timeframe relevant to averting catastrophic change. Australia’s annual emissions more than double when compared to the national inventory, with agriculture producing 54% of the national total. Ruminant livestock emerge as a transformative mitigation opportunity. While success in rapid cuts could revitalise other mitigation efforts, it would require demand-led change and significant producer adaptation. Most siloed analyses neglect such flow-on effects.

Generated Summary

This interdisciplinary Australian case study investigates the implications of excluding short-lived emissions and near-term projections in greenhouse gas (GHG) accounting. The study re-calculates emissions to include short-lived gases and uses 20-year Global Warming Potentials (GWPs) to reveal the far-reaching implications of current GHG accounting methods. The research explores how different emission metrics affect the assessment of climate change, highlighting the importance of addressing short-lived emissions, particularly those from agriculture. The study aims to demonstrate how accounting for short-term gases and assessing emissions over the next 20 years radically alters the importance of emission sectors and offers high-impact mitigation opportunities. The methodology involves analyzing Australian agricultural emissions using both GWP100 and GWP20 to compare the effects of short-lived and long-lived gases, especially those from livestock and agriculture. The study also examines the impacts of these different accounting methods on the framing of climate change, and the potential for transformational changes in sectors like livestock and agriculture to improve climate outcomes.

Key Findings & Statistics

• Australia’s annual emissions more than double when including short-lived gases.
• Agriculture in Australia is the largest source of short-lived O3(T) precursors (CH4, CO, and NMVOCs).
• Agriculture is the greatest source of shorter lived greenhouse emissions globally.
• The livestock sector in Australia is also the largest source of short-lived emissions. It involves large ruminant herds (30 million cattle and 74 million sheep) on extensive grazing land, representing 58% of the nation’s land area.
• Agriculture contributes 54% of the national emissions total when using GWP20.
• When using GWP20, 50% of the national emissions come from livestock.
• Methane (CH4) has an atmospheric life of 12 years and holds important mitigation potential for coming decades.
• Temperature rises could be delayed by 15 years with 40% cuts in CH4.
• Decreasing CH4 emissions by 46% would have the same effect as stopping CO2 emissions entirely.
• Globally, agriculture is the greatest source of shorter-lived greenhouse emissions and offers large-scale opportunities for emissions abatement and carbon sequestration.
• Australia’s CO emissions result predominantly from biomass burning (DCCEE 2012).
• Using GWP100, agriculture contributes 36% of a revised national total of 756MtCO2-e.
• Using GWP20, the revised national total of emissions is 1497Mt.CO2-e, of which 803MtCO2-e (54%) arises from agriculture.
• Livestock production is responsible for 36%-50% of national emissions.

Other Important Findings

• Current greenhouse gas accounting mechanisms and protocols are not sufficient to address the current climate crisis effectively.
• Focusing on short-lived emissions, like methane, can lead to near-term improvements in climate change outlook.
• Using GWP20, focusing on emissions from CH4 and CO (and likely black carbon) will have the greatest benefit in the coming decades.
• Ruminant livestock emerge as a transformative mitigation opportunity.
• Addressing shorter-lived emissions from agriculture offers a way of achieving transformational mitigation of the magnitude that is needed.
• The study highlights the need to reframe mitigation efforts in terms of other important greenhouse gases, their primary sources, and the near-term time frames on which they demand action.
• Australia’s CO emissions result predominantly from biomass burning.
• The study recommends a consumer-driven approach to foster a consumer-driven approach to reduce GHG emissions.
• The study suggests that the financial viability of livestock production would drop for many producers if demand for livestock were to radically decline.

Limitations Noted in the Document

• The study focuses on Australian agriculture, and findings may not be directly applicable to other regions without considering specific local conditions.
• The reliance on existing data from UNFCCC conventions introduces limitations related to the completeness and accuracy of reported emissions.
• The study does not address all potential emission sources, such as those from transport and industrial activities, which could influence the overall findings.
• The study does not include data for black carbon due to lack of Australia-specific data, which limits the comprehensiveness of the analysis.
• The study is limited by the assumptions inherent in the GWP20 metric, particularly regarding the long-term effects of CO2, and may not fully capture the complexities of climate change.

Conclusion

The study underscores the critical need to reframe climate change mitigation by incorporating short-lived emissions, particularly those from agriculture and livestock, which have a substantial impact on near-term warming. The emphasis on the 100-year timeframe (GWP100) in current accounting methods obscures the significant contribution of methane (CH4) and other short-lived gases. Adopting the 20-year Global Warming Potential (GWP20) reveals that livestock production is responsible for a significant portion of national emissions, offering significant mitigation opportunities if addressed. The study emphasizes that transformational mitigation requires not only technological advancements but also shifts in consumer behavior and production practices. The shift in framing to include short-lived emissions reveals that agriculture is the highest emitting sector in Australia, demanding urgent and significant reductions. Furthermore, the research stresses the necessity of addressing livestock emissions to meet climate targets. The authors conclude that by reevaluating emissions using shorter time frames and including short-lived gases, there is an opportunity to accelerate and amplify mitigation efforts. Focusing on the short-term emissions can boost morale by providing near-term targets and increasing the perceived agency of individuals. Ultimately, the study concludes that the current approach of gradual change is insufficient, and a comprehensive shift is needed to address the urgent need for action by re-evaluating emissions and reframing the approach to climate change.