Explore the vast range of titles available.

Once an external factor has been deemed likely to influence human health and a dose response function is available, an assessment of its health impact or that of policies aimed at influencing this and possibly other factors in a specific population can be obtained through a quantitative risk assessment, or health impact assessment (HIA) study. The health impact is usually expressed as a number of disease cases or disability-adjusted life-years (DALYs) attributable to or expected from the exposure or policy. We review the methodology of quantitative risk assessment studies based on human data. The main steps of such studies include definition of counterfactual scenarios related to the exposure or policy, exposure(s) assessment, quantification of risks (usually relying on literature-based dose response functions), possibly economic assessment, followed by uncertainty analyses. We discuss issues and make recommendations relative to the accuracy and geographic scale at which factors are assessed, which can strongly influence the study results. If several factors are considered simultaneously, then correlation, mutual influences and possibly synergy between them should be taken into account. Gaps or issues in the methodology of quantitative risk assessment studies include 1) proposing a formal approach to the quantitative handling of the level of evidence regarding each exposure-health pair (essential to consider emerging factors); 2) contrasting risk assessment based on human dose–response functions with that relying on toxicological data; 3) clarification of terminology of health impact assessment and human-based risk assessment studies, which are actually very similar, and 4) other technical issues related to the simultaneous consideration of several factors, in particular when they are causally linked.

The Paris Agreement introduces long-term strategies as an instrument to inform progressively more ambitious emission reduction objectives, while holding development goals paramount in the context of national circumstances. In the lead up to the twenty-first Conference of the Parties, the Deep Decarbonization Pathways Project developed mid-century low-emission pathways for 16 countries, based on an innovative pathway design framework. In this Perspective, we describe this framework and show how it can support the development of sectorally and technologically detailed, policy-relevant and country-driven strategies consistent with the Paris Agreement climate goal. We also discuss how this framework can be used to engage stakeholder input and buy-in; design implementation policy packages; reveal necessary technological, financial and institutional enabling conditions; and support global stocktaking and increasing of ambition.The Deep Decarbonization Pathways Project develops a framework to design low-emission development pathways. This Perspective discusses the framework and how it can support the development of national strategies to meet climate targets, as well as help achieve stakeholder engagement.

In this paper we analyze research gaps and identify new directions of research in relation to a number of facets of the Paris Agreement, including the new 1.5 °C objective, the articulation between near-term and long-term mitigation pathways, negative emissions, verification, climate finance, non-Parties stakeholders, and adaptation.

Reference emission scenarios in the literature have been the target of criticisms that suggest they convey too optimistic views on spontaneous energy-GDP decoupling of emerging countries economies. This article focuses on the case of India. It explores the role of current suboptimalities of the Indian power sector (structural under-investment in the sector leading to capacity shortage, power cuts and low efficiency) on future energy-GDP decoupling. To do so, it uses a hybrid general equilibrium framework, in which these suboptimalities are explicitly introduced. The results highlight that whether the constraints on investments in the power sector persist or not leads to contrasted trends in energy-GDP decoupling and GHG emissions. Over the short-term, capital scarcity in the power sector constrains the development of energy-intensive activities and therefore leads to higher energy-GDP decoupling. But on the longer-term, constrains on the power sector capacity limits substitution from fossil fuels to electricity, which entails both a low energy-GDP decoupling and a constraint on GDP growth when oil prices are high. The alleviation of suboptimalities appears thus as an insurance policy towards future oil price increase.

Seven long-term prospective studies representing the energy trajectories consistent with a Factor Four, i.e. a 75% reduction of greenhouse gases emissions in 2050 in France have been identified. We analyze their methodology and the high dispersion of results. Then we discuss the role of scenario-making. Among them, only one of the scenarios achieves the Factor Four, thereby showing the limitations of these studies. On the methodological side, the engineering models used appear as black boxes, each using their own technological hypotheses and not readily understandable by the non-specialist. Therefore, exchanges between modelers, economists, technologists, sociologists and representatives of the civil society are a key factor for these scenario elaboration as their legitimacy stems from social and politic appropriation of scientific results.

This paper analyzes the renewal of the intellectual constructs that have contributed to the Paris Agreement. In this paradigm shift, the concept of Intended Nationally Determined Contribution (INDC) has created the space in which Nation-states have been free to engage in the process while setting their own goals for the medium term. A second key concept, the Deep Decarbonization Pathways (DDP), although less institutionalized, has been an effective tool to describe how these medium-term national targets were likely to fit into a longer-term perspective of global mitigation scenarios as studied in particular by the IPCC. The dialectical interaction between these two concepts should result in a more ambitious definition of national climate objectives and consequently in the design and implementation of stronger national climate policies.

Background: Frequent car use contributes to health and environmental issues such as air pollution, climate change and obesity. Active and sustainable mobility (bike, walk, public transport, car sharing) may address these issues. Different strategies have been implemented in past research, involving hard levers, aimed at modifying the economical or geographical context (e.g., free public transport), and soft levers, aimed at modifying psychological processes (e.g., personalised transport advice). However, few studies have combined both hard and soft levers. In addition, few have used robust methodologies (e.g., randomised controlled trials), followed behavioural changes in the longterm, and been anchored in behaviour change theories. InterMob aims to address these limits by implementing a 24-month randomised controlled trial including hard and soft levers. The objectives of InterMob are to a) evaluate the effectiveness of an experimental arm versus an active controlled arm, and b) identify the processes of mobility change.Methods: Regular car users living in Grenoble (N = 300) will be recruited and randomised to one of the two arms. The experimental arm consists in a six-month intervention combining hard levers (free access to transport/bikes), and soft levers (e.g., personalised transport advice). The control arm consists in a six-month intervention aimed at raising awareness on air pollution and its health effects. Both arms will include eight evaluation weeks (spread out over 24 months) based on a GPS, an accelerometer, and a pollution sensor. Moreover, participants will complete mobility logbooks and surveys measuring psychological constructs, socio-economical, and socio-spatial characteristics.Discussion: InterMob will assess the effectiveness of two interventions aimed at reducing car use within regular car users in the short-, mid- and long-term. Moreover, InterMob will allow to better understand the psychological processes of behaviour change, and the socio-economical and geographical conditions under which the intervention is efficient in reducing car use. Finally, the benefits of mobility change in terms of physical activity, quality of life, and exposure to pollution will be quantified.Trial registration: Clini calTr ials. gov: NCT05096000 on 27/10/2021 (retrospectively registered).

The limitation of global warming below 2°C requires rapid and significant deployment of renewable energies in the power sector. Policies to support innovation and diffusion of renewables have been implemented for more than 20 years. There is currently a debate surrounding their economic and environmental efficiency and the right balance between support for innovation and support for diffusion. This article sheds light on the stakes of this debate by presenting the results of the econometric literature which evaluates the effect of these policies and compares these results with the main conclusions of non-econometric studies. The results show that innovation policies and diffusion policies have a positive impact on renewable energies and so confirm non-econometric studies. However, they reveal differentiated effects