Planetary Health Research Digest
Authors: Sam Hinsley
Journal: The Lancet Planetary Health (2022)

As methods to identify the contribution of climate change to extreme weather events have improved, so too has the tendency to frame the resulting emergencies as being caused by climate change. While this frame is intended to communicate the urgency of climate change, it risks glossing over the pre-existing vulnerabilities that are also necessary for an emergency to exist. Myanna Lahsen (Linköping University, Sweden) and Jesse Ribot (American University, DC, USA) review this challenge and present examples from around the world, especially Brazil, of times when environmental leaders have argued against attributing extreme event-related emergencies principally to climate change. They argue that people affected by emergencies rarely see climate change as the sole cause and that they instead cite more immediate factors. By contrast, local and national governments might choose to blame climate change as a way to avoid taking responsibility for their role in perpetuating local vulnerabilities. In such cases a climate change-centric framing of the crisis can therefore, at times, be misleading. The authors argue that any attribution has an inherently political dimension, and that the local context of a crisis needs to be accounted for instead of any fixed style of reporting. Reducing green house gases consistent with 1·5°C of future warming will not be possible solely with technological innovations and other supply-side solutions. Demand-side solutions and consumer choice will therefore have a large role to play, but it is not yet clear how these choices might impact on human wellbeing. Felix Creutzig (Mercator Research Institute on Global Commons and Climate Change, Germany) and colleagues explored the contributions that demand-side solutions could have in mitigating climate change and how these solutions are likely to affect human wellbeing. Among the 306 combinations of demand-side options and wellbeing measures included, the effects on wellbeing were predominantly positive (79%), with 18% neutral and 3% negative, and could reduce emissions by 40–80% overall. The greatest improvements in wellbeing were in terms of health, air quality, and energy access, which have also been the most studied, while the social determinants of wellbeing have been less well characterised and had more uncertain results. These findings highlight the potential of demand-side solutions, and the authors note, present opportunities to redesign infrastructures and services to best enable them. Existing roadmaps to achieve net-zero emissions by mid-century are predicated on the widescale adoption and implementation of both renewable energy and carbon capture and storage (CCS) technologies. However, the models used to inform these plans have been criticised for not accounting for more recent declines in the costs of renewable energy technologies. Neil Grant (Imperial College London, UK) and colleagues used an integrated assessment model with up to date cost trajectories for renewable energy technologies to assess how the value of CCS technologies in reducing emissions is affected by low-cost renewables. Compared with scenarios using historical renewable costs, the value of CCS fell by 15–96% with the updated costs. The greatest decrease in value was for power/hydrogen generation, where low-cost renewables outcompete CCS for decarbonising the industry. CCS retained the most value for capturing process emissions in heavy industry (eg, in cement production), and as part of sustainable bioenergy production. The authors conclude that renewable energy should be pursued as the main approach to decarbonisation, but targeted use of CCS, particularly where it does not directly compete with renewables, can still provide substantial cost reductions overall. Air pollution poses a serious threat to public health, especially for people of minority racial or ethnic groups, who often face disproportionately higher exposures. Such disparities have been reported in the US, but overall patterns across the country have rarely been analysed. Jiawen Liu (University of Washington, WA, USA) and colleagues investigated how exposure to air pollutants varies in the US by race/ethnicity and income and found that one of the included ethnic/racial minority groups had the greatest exposures for all included pollutants, with the largest disparities for NO2. Disparities varied across states, although at least one racial/ethnic minority group experienced exposure to one or more pollutants that was at least 5% higher than the national average in all of the contiguous states. When the effects of income were compared to those of race/ethnicity, the disparities were 1·1 to 21 times higher for ethnic/racial groups than income groups. The ubiquitous nature of these disparities is a serious environmental justice concern for which state-level action could be an important solution, the authors suggest.