Planetary Health Research Digest

Abstract

Most climate change mitigation strategies depend on long-term reductions in carbon dioxide emissions. However, for greenhouse gases with a shorter atmospheric presences, particularly methane, shorter-term targets might be more desirable. Ilissa Ocko (Environmental Defense Fund, USA) and co-authors investigated the potential of existing methane abatement measures to contribute to future climate change mitigation. They divided measures into those that were economically feasible and those that were technically possible and estimated their effects at different implementation timescales. The greatest effects could be achieved if all measures were implemented by 2030, with a 57% reduction in emissions, translating to an avoided quarter of a degree of warming by mid-century, and potentially avoiding more than half a degree by the end of the century. Delayed implementation of such measures was associated smaller reductions in future warming. The authors conclude that methane abatement measures should be scaled up in the short-term and can act as a powerful complement to longer-term carbon reduction strategies. Many post-industrial cities, such as London, Paris, and New York have more deprived eastern areas compared to other parts of the cities. While this is anecdotally accepted, the factors driving these patterns have received relatively little research attention. Stephan Heblich (University of Toronto, Canada) and co-authors used the historical locations of roughly 5000 industrial chimneys in the UK to test whether industrial development influenced subsequent neighbourhood sorting. Using census data on residents' occupations before and during the industrial revolution, as well as between the 1970s and 2011, the authors found larger proportions of unskilled workers (a measure of neighbourhood socioeconomic status) in areas downwind of industrial chimneys, with prevailing winds blowing emissions eastward. This effect persisted, even after the decline of coal burning within the cities and the passage of the Clean Air Acts. By understanding the original causes of neighbourhood sorting and modelling the dynamic effects maintaining these structures, these results can show how these spatial inequalities might be overcome. While climate change denial by overemphasising research uncertainty is a well known strategy, other framings used to delay climate action have received less attention. Analysing public communications from fossil fuel suppliers can show other ways that the industry has influenced the public discourse on climate change. Geoffrey Supran and Naomi Oreskes (Harvard University, USA) analysed climate change communications from ExxonMobil to determine what rhetoric and framing was used to present discussions of anthropogenic global warming. They found that, compared with internal communications and academic publications, the public communications favoured discussions of climate “risk” and consumer “demand” for energy to create a framing in which the reality of climate change is downplayed, fossil fuel lock-in is assumed to be normal and inevitable, and individual responsibility for energy use is emphasised. This framing, particularly the focus on individual responsibility of the consumer, is similar to that used by the tobacco industry, and undermines litigation, regulation, and activism, while allowing the industry enough leeway to avoid being held responsible for propagating outright misinformation. Limiting future temperature increases to the 1·5°C target recommended by the IPCC will require substantial reductions in the extraction of fossil fuels. Some fossil fuel-producing companies have set out pathways to become carbon neutral, but it is not clear whether the industry is willing to make the reductions to exploration and extraction that are needed. Dario Kenner (University of Sussex, UK) and Richard Heede (Climate Accountability Institute, USA) looked at the examples of the four largest investor-owned fossil fuel-producing companies, Chevron, ExxonMobil, BP, and Royal Dutch Shell. They found that while the four companies are at different phases of their response to the disruption caused by increased awareness of the climate crisis, with BP and Shell announcing plans to be net zero by mid-century, none are planning to phase out extraction. They argue that the incentives to executives and directors make it in their interests to maintain demand for oil and gas, and companies would therefore be unlikely take a lead on a low low-carbon transition that could hurt their immediate profits. Instead, the authors call for increased external pressure from policy makers, as has been instrumental in the transition away from coal as a source of energy.