Scenarios that limit global warming to 1.5°C rely on a combination of interventions to reduce greenhouse gas emissions and capture carbon dioxide. However, the extent to which lifestyle change... Show moreScenarios that limit global warming to 1.5°C rely on a combination of interventions to reduce greenhouse gas emissions and capture carbon dioxide. However, the extent to which lifestyle change contributes to mitigation relative to technological change over time remains understudied. Here, we present a scenario model that incorporates extensive supply-side technological transformations while excluding lifestyle changes. By adapting a global supply-use table from EXIOBASE using elements from Shared Socioeconomic Pathway 1 and a mitigation pathway consistent with the 1.5°C target, we assess how household footprints evolve in 2030 and 2050 and the extent to which technological change alone can mitigate greenhouse gas emissions. We modeled footprints for 49 countries/regions, with a focus on the EU27. Our scenario results indicate that while technological change can substantially reduce emissions, the reductions are ultimately insufficient to achieve the 1.5°C target. Eight EXIOBASE regions, including three EU27 countries, are on a 1.5°C-consistent trajectory with just technological advancements in 2030. However, by 2050, no countries are projected to meet the 1.5°C-compatible target. The average EU27 overshoot for household footprints approaches 2.2 tCO2e/cap in 2030 and 3.1 tCO2e/cap in 2050. Global overshoots are more moderate at 0.3 tCO2e/cap in 2030 and 2.0 tCO2e/cap in 2050. Our results highlight the critical role of household lifestyle transformation in climate change mitigation. Future research can explore the diverse lifestyle change pathways necessary to align with the aspirational 1.5°C target outlined in the Paris Agreement. Show less
The aviation sector needs to reduce its environmental impacts, like climate change and air pollution. New hybrid-electric aircraft concepts may contribute to abating part of these impacts. But to... Show moreThe aviation sector needs to reduce its environmental impacts, like climate change and air pollution. New hybrid-electric aircraft concepts may contribute to abating part of these impacts. But to what extent and under which conditions? This study addresses these questions in the context of regional aviation and identifies technologies and concrete actions required for more environmentally sustainable aviation. The environmental impacts of emerging hybrid-electric aircraft configurations deployed in 2030, 2040, and 2050 have been comprehensively quantified using prospective life cycle assessment. The entire life cycle of the conventional and hybrid-electric aircraft configurations was encompassed, covering various technologies and systems like batteries, fuel cells, hydrogen, and selected alternative aviation fuel (AAF) systems. For these elements, detailed life cycle inventories stemming from primary data, literature, and prospective environmental databases were used, and uncertainty was evaluated. Results showed that hybrid-electric aircraft with Li-ion batteries appear as a promising transition technology in the short-term while aircraft propelled by fuel cells using hydrogen from electrolysis yield important environmental benefits relative to conventional aircraft in longer time horizons. In contrast, the studied AAFs present little or no environmental benefits when considering environmental impacts holistically, demonstrating the need to revise existing AAF frameworks and incentives globally. Environmental burden-shifting from flight emissions in conventional aircraft systems to airport operations and aircraft manufacturing in hybrid-electric aircraft is also observed in the results, thus calling for strengthened support to airports in their sustainability management and increased integration of ecodesign practices in future aircraft design and development. Show less
While the importance of reducing meat loss and waste is acknowledged due to its substantial environmental impacts, the aspect of animal welfare largely remains unaddressed. The suffering and death... Show moreWhile the importance of reducing meat loss and waste is acknowledged due to its substantial environmental impacts, the aspect of animal welfare largely remains unaddressed. The suffering and death that is inflicted on animals to produce food that is never eaten remains invisible. This study aims to bridge the gap between food loss and waste (FLW) accounting literature and animal welfare considerations. It achieves this by estimating the number of animal lives embodied in meat loss and waste of six major meat-producing species along the food supply chain and by modelling three potential reduction scenarios. It shows that approximately 18 billion animal lives were embodied in losses and waste of global meat production and consumption in 2019. The scenarios reveal that wasted and lost animal lives could be reduced by 7.9 billion if best regional efficiencies were mainstreamed, and by 4.2 or 8.8 billion if Sustainable Development Goal 12.3 was implemented, achieving a 50% loss and waste reduction in the downstream or whole supply chain, respectively. Considering species specific conscience and sentience, and previous recommendations, the analysis finds leverage points for change at the consumption stage in developed, high-income countries, in Industrialized Asia, judging by absolute, and in North America and Oceania, judging by per-capita numbers, as well as in top countries of FLW and animal life loss. It further identifies trade-offs for animal welfare between reducing FLW of different meat types, especially chicken and beef, and reducing production-based losses while keeping emissions and resource use low and supporting food security. Show less
Rong, Y.; Dias Rodrigues, J.F.; Tukker, A.; Behrens, P.A. 2022
