A scenario assessment of the global mitigation effort in the light of the 2035 climate finance goal

Mitigation implications of remaining carbon budget allocation rules for Mediterranean countries

The Mediterranean Basin is a climate change hotspot, experiencing accelerated warming and strong environmental vulnerability. Mediterranean Sea surface temperatures have increased by approximately 1.5 °C over the past four decades, underscoring the urgency of coordinated mitigation efforts. In this context, this study examines how alternative allocation criteria for distributing the remaining carbon budget compatible with the Paris Agreement (well below 2 °C) affect emission pathways among the 21 signatory countries of the Barcelona Convention. Using a mitigation pathway derived from the Global Change Analysis Model, the analysis evaluates emissions trajectories from 2030—anchored in current Nationally Determined Contributions—through 2100. Five allocation principles are assessed: Grandfathering, Per Capita, Per Capita Convergence, Equal Cumulative Per Capita, and Ability to Pay, each reflecting different trade-offs between equity and feasibility. Results indicate that, irrespective of the allocation rule, rapid and sustained decarbonisation is unavoidable. At current emission levels, the regional carbon budget would be exhausted by 2035, requiring average annual reductions of approximately 6% between 2030 and 2050 to meet global targets. While population-based criteria yield the largest regional budget and are more equitable, they imply more disruptive transitions. In contrast, emissions-based approaches are more feasible but risk reinforcing existing inequalities. These findings highlight significant implications for fossil fuel-dependent economies and stress the importance of regional cooperation. The Barcelona Convention emerges as a key platform to facilitate equitable burden-sharing and coordinated climate action in the Mediterranean region.

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Comparison of major EU and climate scenarios for 2040: what contribution from energy savings and sufficiency?

Extended abstract 3-288-26 While the role of energy demand reduction to meet climate objectives is increasingly considered, most scenarios do not fully reflect this potential, and only a few explore low-demand pathways. Literature reviews show that this is not only due to preferences of modellers or scenario users, but also to structural limitations of models.This analysis investigates how main energy and climate scenarios for Europe balance demand and supply-side options and how this is informing policy making, with a particular focus on the setting of EU 2040 targets. It first focuses on a comparison and benchmark of scenarios. Eight prominent scenarios by institutions, think tanks and an NGO are selected on criteria of comprehensiveness, detail of modelling and compliance with the Paris Agreement. They are then characterised using 14 indicators that reflect their outcomes (GHG budget, fossil fuel consumption) and their use of major levers (renewables, hydrogen, electrification, reduction of consumption, carbon sinks). These numbers are then compared to targets and thresholds drawn from reports on climate objectives and the potential of various options by the European Scientific Advisory Board on Climate Change (ESABCC). This benchmark of the relative ambition and feasibility of scenarios shows a positive correlation between demand reduction – compared to stronger reliance on supply-oriented options – and climate ambition, feasibility and robustness, providing major lessons for the EU’s 2040 target setting. The analysis then reviews detailed assumptions on energy demand for buildings and mobility, comparing the low-demand CLEVER scenario with the Commission's S3 – one of the few providing such detail. Beyond the transparency gap in data, this comparison reveals the prevalence in a scenario like S3 of trend-based projections of activity, contrasting with CLEVER’s explicit modelling of energy services. Analysing this gap can help to inform policies about the potential of energy savings. Read the full abstract. Download presentation.

Factors influencing the low-carbon transition: Evidence from the EU economies

Decarbonizing the economy effectively mitigates climate change, accelerates the transition to sustainable development, and corresponds to the Kyoto Protocol and Paris Climate Accords. The key objective of this research is to estimate the influence of different social, economic, political and technological factors on decarbonization processes. The scientific novelty of the study is that it investigates decarbonization from a dual perspective, assessing it both in terms of greenhouse gas (GHG) emissions levels and carbon intensity of gross domestic product (GDP). This research applies random-effects generalized least squares regression, fixed-effects robustness checks and dynamic System GMM for 27 EU economies in 2013–2021. The results indicate that (i) renewable energy is a vital decarbonization driver (a 10-percentage-point increase in the share of renewable energy leads to a decrease in the amount of GHG emissions by 1.52 thousand metric tons and to a decrease in the carbon intensity of GDP by 0.14 metric tons/thousand USD). (ii) A larger service sector and higher technological employment also contribute positively to the low-carbon transition, while (iii) corruption acts as an important institutional barrier. (iv) GDP per capita is associated with lower carbon intensity and emissions, supporting the view that more advanced economies are better positioned to implement sustainable transformation. Research results provide specific policy implications for designing more effective climate and energy policies, including green finance development, virtual economy growth, and innovation implementation.

A mix of policies is needed to close the climate ambition gap

We compare eight integrated assessment models to analyze the effects of additional climate policies targeting production and energy supply, consumption and energy demand, and the land sector on top of a moderate carbon price. We find that the combination of these additional policies can close the gap between well-below 2 °C and 1.5 °C pathways with overshoot assuming the same carbon price trajectory. While production and energy supply policies are necessary to decarbonize the energy sector in the long run, consumption and demand-side transformations can reduce emissions especially in the short-term, thus enabling lower cumulative emissions leading to lower peak temperature. Additional land policies can not only reduce CO2 emissions further, but also target non-CO2 emissions and reduce global warming even further.

Emission pathways consitent with 2C global temperature limit