James Glynn

Efficient and Equitable Climate Change Policies

This report describes the Integrated Assessment Model TIAM-MACRO, which is a Ramsey-type macroeconomic growth model linked with a technology-rich engineering model of the energy-system and with a stylized sub-model of climate change. TIAM-MACRO contributes to coherent and consistent policy analyses at both the world and regional level and correlates demand for energy services to macro-economic developments across regions and time until the end of the 21st century. With the help of this model, two contrasting scenarios are defined related to the reference development (BASE) case and the 2 °C (2DS) case that follow long-term policies on climatic change mitigation in the spirit of the Paris agreement. Finally, we define ex-post market and non-market damages together with the damages related to Local Atmospheric Pollutants (LAP). The stringency of the 2DS case requires the complete restructuring of the energy and transport systems to be relying on carbon-free technologies and fuels together with technologies of negative emissions, at high costs. The study concludes that carbon policies not only consist of an insurance against the risk of climate change but also improve the ambient air quality, as they have secondary benefits that compensate for part of the cost of carbon control. However, the stringency of the 2DS case is so demanding that the cost of climate policies is above benefits.

The Role of Population, Affluence, Technological Development and Diet in a Below 2 °C World

The rise in anthropogenic greenhouse gas emissions and the resultant temperature anomaly in the global climate can be simplified to a function of (1) the global population, (2) economic activity and (3) technological development for thought experiments. Diet, given the embodied process emissions in producing food, is also acknowledged as an important factor. Growth in the first two factors tends to increase environmental impacts while technological development can reduce them. In this chapter, the impact from these four variables, their interdependencies and importance are illustrated. To do so, three different model frameworks are combined namely IPAT, Ecological Footprint and Integrated Assessment Modelling, to illustrate the challenges to finding pathways to maintain a well below 2 °C world. The model setup developed for this chapter estimates the global mean temperature increase to 2100 and the needed land area to support human life as a function of population, affluence, technological development and diet. It is shown that focusing on technology development alone will likely not be enough to mitigate global warming and stay well below a 2 °C temperature increase. Therefore, the discussion about population, consumption, development and diet shifting should be high on the agenda for reducing energy demands and for increasing the feasibility of maintaining a well below 2 °C world.

From 2 °C to 1.5 °C: How Ambitious Can Ireland Be?

The current climate policy of Ireland was set according to a 2 °C temperature rise target. Pursuing a 1.5 °C temperature increase limit requires ratcheting of decarbonisation ambition. A large ensemble of scenarios are generated with decreasing carbon budgets, and the challenges of not exceeding these carbon budgets are compared with the current 2 °C climate policy scenario. The results indicate that a national carbon budget compatible with a 1.5 °C target would need to be almost three times smaller than the carbon budget resulting from the current national climate policy. This budget is technically feasible, but extremely challenging with the current technology assumptions. A carbon budget which would be midway between 1.5 and 2 °C appears much more plausible. Cost effective decarbonisation rates are non-linear in the near-medium term, contrary to the current policy, and more ambitious carbon budget targets can only be achieved through much stronger near-term mitigation efforts than suggested by the current nationally determined contribution. Marginal Abatement Costs (MAC) increase exponentially with increasing ambition. Delayed action causes a step change increase in MAC as well as reduces the level of feasible decarbonisation ambition.

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.

Gas Security of Supply in the European Union

The EU remains widely dependent on external gas supplies, with imports representing 70% of its consumption in 2013. Member States have different import profiles with divergent levels of dependency ...