Steve Pye

Health and climate change: policy responses to protect public health

The 2015 Lancet Commission on Health and Climate Change has been formed to map out the impacts of climate change, and the necessary policy responses, in order to ensure the highest attainable stand ...

The Lancet Countdown on health and climate change: from 25 years of inaction to a global transformation for public health

The Lancet Countdown tracks progress on health and climate change and provides an independent assessment of the health effects of climate change, the implementation of the Paris Agreement, 1 and th ...

Achieving net-zero emissions through the reframing of UK national targets in the post-Paris Agreement era

The Paris Agreement provides an international framework aimed at limiting average global temperature rise to well below 2°C, implemented through actions determined at the national level. As the Agreement necessitates a ‘net-zero’ emissions energy system prior to 2100, decarbonisation analyses in support of national climate policy should consider the post-2050 period. Focusing solely on mitigation objectives for 2030 or 2050 could lead to blindsiding of the challenge, inadequate ambition in the near term, and poor investment choices in energy infrastructure. Here we show, using the UK as an example, that even an ambitious climate policy is likely to fall short of the challenge of net-zero, and that analysis of the post-2050 period is therefore critical. We find that the analysis of detailed, longer term national pathways which achieve net-zero is important for future reassessment of ambition under Nationally Determined Contributions (NDCs).

Improving deep decarbonization modelling capacity for developed and developing country contexts

Energy models are essential for the development of national or regional deep decarbonization pathways (DDPs), providing the necessary analytical framework to systematically explore the system transitions that are required. However, this is challenging due to the long time horizon, the numerous data requirements and the need for transparent, credible approaches that can provide insights into complex transitions. This article explores how this challenge has been met to date, based on a review of the literature and the experiences of practitioners, drawing in particular on the Deep Decarbonization Pathways Project (DDPP), a collaborative effort by 16 national modelling teams. The article finds that there are a range of modelling approaches that have been used across different country contexts, chosen for different reasons, with recognized strengths and weaknesses. The key motivations for use of a given approach include being fit-for-purpose, having in-country capacity and the intertwined goals of transparency, communicability and policy credibility. From the review, a conceptual decision framework for DDP analysis is proposed. This three step process incorporates policy priorities, national characteristics and the model-agnostic principles that drive model choices, considering the needs and capabilities of developed and developing countries, and subject to data and analytical practicalities. Finally an agenda for the further development of modelling approaches is proposed, which is vital for strengthening capacity. These include a focus on model linking, incorporating behaviour and policy impacts, the flexibility to handle distinctive energy systems, incorporating wider environmental constraints and the development of entry-level tools. The latter three are critical for application in developing countries. Policy relevance Following the Paris Agreement, it is essential that modelling approaches are available to enable governments to plan how to decarbonize their economies in the long term. This article takes stock of current practices, identifies the strengths and weaknesses of existing approaches and proposes how capacity can be strengthened. It also provides some practical guidance on the process of choosing modelling approaches, given national priorities and circumstances. This is particularly relevant as countries revisit their Nationally Determined Contributions to meet the global objective of remaining well below a 2°C average global temperature increase.

Exploring national decarbonization pathways and global energy trade flows: a multi-scale analysis

The role of fossils fuels in national economies will change radically over the next 40 years under a strong climate regime. However, capturing this changing role through national-based analyses is challenging due to the global nature of fossil fuel demand and resulting trade patterns. This article sets out the limitations of existing national-scale decarbonization analyses in adequately capturing global conditions and explores how the introduction of a global modelling framework could provide vital insights, particularly for those countries that are dependent on fossil fuel exports or imports. The article shows that fossil fuel use will significantly decline by 2050, although gas will have an important transition role. This leaves large fossil fuel exporters exposed, the extent of which is determined by mitigation action in different regions and especially by the pathways adopted by the larger Asian economies. We find that global-scale models provide critical insights that complement the more detailed national analyses and should play a stronger role in informing deep decarbonization pathways (DDPs). They also provide an important basis for exploring key uncertainties around technology uptake, mitigation rates and how this plays out in the demand for fossil fuels. However, use of global models also calls for improved representation of country specifics in global models, which can oversimplify national economic and political realities. Using both model scales provides important insights that are complementary but that can challenge the other’s orthodoxy. However, neither can replace the other’s strengths. Policy relevance: In recent years, how global fossil fuel markets will evolve under different climate regimes has been subject to much debate and analysis. This debate includes whether investments in fossil fuel production still make sense or will be exposed in the future to liabilities associated with high carbon prices. This is important for governments who need to develop coherent policy in relation to fossil fuel sectors and their role as drivers of economic growth and in providing for domestic energy needs. This article argues that national analyses need to be fully cognizant of the global-scale transition, which can be informed by using a multi-scale modelling approach.

The Lancet Countdown on health benefits from the UK Climate Change Act: a modelling study for Great Britain

BACKGROUND Climate change poses a dangerous and immediate threat to the health of populations in the UK and worldwide. We aimed to model different scenarios to assess the health co-benefits that result from mitigation actions. METHODS In this modelling study, we combined a detailed techno-economic energy systems model (UK TIMES), air pollutant emission inventories, a sophisticated air pollution model (Community Multi-scale Air Quality), and previously published associations between concentrations and health outcomes. We used four scenarios and focused on the air pollution implications from fine particulate matter (PM2·5), nitrogen dioxide (NO2) and ozone. The four scenarios were baseline, which assumed no further climate actions beyond those already achieved and did not meet the UKs Climate Change Act (at least an 80% reduction in carbon dioxide equivalent emissions by 2050 compared with 1990) target; nuclear power, which met the Climate Change Act target with a limited increase in nuclear power; low-greenhouse gas, which met the Climate Change Act target without any policy constraint on nuclear build; and a constant scenario that held 2011 air pollutant concentrations constant until 2050. We predicted the health and economic impacts from air pollution for the scenarios until 2050, and the inequalities in exposure across different socioeconomic groups. FINDINGS NO2 concentrations declined leading to 4 892 000 life-years saved for the nuclear power scenario and 7 178 000 life-years saved for the low-greenhouse gas scenario from 2011 to 2154. However, the associations that we used might overestimate the effects of NO2 itself. PM2·5 concentrations in Great Britain are predicted to decrease between 42% and 44% by 2050 compared with 2011 in the scenarios that met the Climate Change Act targets, especially those from road traffic and off-road machinery. These reductions in PM2·5 are tempered by a 2035 peak (and subsequent decline) in biomass (wood burning), and by a large, projected increase in future demand for transport leading to potential increases in non-exhaust particulate matter emissions. The potential use of biomass in poorly controlled technologies to meet the Climate Change Act commitments would represent an important missed opportunity (resulting in 472 000 more life-years lost from PM2·5 in the low-greenhouse gas scenario and 1 122 000 more life-years lost in the nuclear power scenario from PM2·5 than the baseline scenario). Although substantial overall improvements in absolute amounts of exposure are seen compared with 2011, these outcomes mask the fact that health inequalities seen (in which socioeconomically disadvantaged populations are among the most exposed) are projected to be maintained up to 2050. INTERPRETATION The modelling infrastructure created will help future researchers explore a wider range of climate policy scenarios, including local, European, and global scenarios. The need to strengthen the links between climate change policy objectives and public health imperatives, and the benefits to societal wellbeing that might result is urgent. FUNDING National Institute for Health Research.

Decarbonizing the EU Energy System

The Paris Agreement of December 2015 under the United Nations Framework Convention on Climate Change (UNFCCC) was a historically significant landmark agreement that covers almost all of the world’s emissions. In line with scientific findings, the EU’s objective (in the context of necessary reductions by developed countries as a group) is to reduce greenhouse gas emissions by 80%–95% by 2050 compared to 1990. This calls for a deep, rapid transformation of the energy system and an assessment of the role of policy instruments such as carbon pricing for this transition. The challenge of decarbonization is also set against the context of a limited carbon budget and the concept of “unburnable carbon,” which has implications not only for Europe but for the globe.

How Low Can We Go? The Implications of Delayed Ratcheting and Negative Emissions Technologies on Achieving Well Below 2 °C

Pledges embodied in the nationally determined contributions (NDCs) represent an interim step from a global “no policy” path towards an optimal long-term global mitigation path. However, the goals of the Paris Agreement highlight that current pledges are insufficient. It is, therefore, necessary to ratchet-up parties’ future mitigation pledges in the near-term. The ambitious goals of remaining well below 2 °C and pursuing reductions towards 1.5 °C mean that any delay in ratcheting-up commitments could be extremely costly or may even make the targets unachievable. In this chapter, we consider the impacts of delaying ratcheting until 2030 on global emissions trajectories towards 2 °C and 1.5 °C, and the role of offsets via negative emissions technologies (NETs). The analysis suggests that delaying action makes pursuing the 1.5 °C goal especially difficult without extremely high levels of negative emissions technologies (NETs), such as carbon capture and storage combined with bioenergy (BECCS). Depending on the availability of biomass, other NETs beyond BECCS will be required. Policymakers must also realise that the outlook for fossil fuels are closely linked to the prospects for NETs. If NETs cannot be scaled, the levels of fossil fuels suggested in this analysis are not compatible with the Paris Agreement goals i.e. there are risks of lock-in to a high fossil future. Decision makers must, therefore, comprehend fully the risks of different strategies.

Chapter 8 – Conclusions

While the European Union is well on track with the implementation of its energy and climate policies, it is facing a complex situation. The energy transition will require new market designs which deliver on climate policy targets, ensure energy security, and provide affordable energy services to final consumers. At the same time national policies are to some extent contrasted by the launch of the Energy Union. This chapter provides some concluding thoughts on this energy transition, based on the analysis presented in this section on Europe’s Energy Policy Landscape.

Key Challenges Ahead

This chapter sets out the key challenges ahead for the European energy system, as it transitions to one that is low-carbon, both secure and reliable, and meets the energy needs of European citizens. It highlights the need for a comprehensive and cohesive policy package, as further considered in more detail in Chapter 33, Developing the Policy Package.