The most ambitious plans to reduce emissions can likely still limit peak warming to below 1.6°C, with a low overshoot outcome. However, when considering real-world challenges, especially government effectiveness in implementing policies, this chance drops significantly up to 50%. A new study in Nature Climate Change highlights critical challenges in meeting the Paris Agreement’s long-term goals given recent global emissions trends and differing capacities.

In the global challenge of climate change, the feasibility of meeting the temperature goals set by the Paris Agreement is increasingly challenging due to institutional and technological constraints.

A new study published in Nature Climate Change highlights critical challenges in meeting the Paris Agreement’s long-term goals given recent global atmosphere-damaging emissions trends.

The study highlights that while technological advancements in low-carbon energy technologies are progressing, institutional capabilities, such as the effectiveness of government policies, significantly influence the successful deployment of these technologies at the scale required by climate goals.

“The findings suggest that without substantial improvements in global governance and rapid policy interventions, the likelihood of limiting global warming to the agreed targets diminishes,” said CMCC’s Laurent Drouet, one of the study’s authors. “This research highlights the urgency of improving institutional frameworks and technological innovations to combat climate change effectively.”

Led by the Center for Global Sustainability (CGS) at the University of Maryland, in partnership with members of the ENGAGE project, the study makes use of eight state-of-the-art global integrated assessment models (IAMs) that are multi-regional and process-based. Using a set of 20 different feasibility scenarios, the analysis found that the institutional dimension (i.e. accounting for limits of countries to enable effective environmental regulation) has the largest influence on feasible peak temperature.

The Paris Agreement’s goal to limit global warming to 1.5°C demands rapid reductions in CO₂ emissions and heightened attention to non-CO₂ greenhouse gasses. Despite advancements in clean energy, global CO₂ emissions have risen steadily over the past 3 years following the initial decline during the COVID-19 pandemic in 2020. The analysis reveals that even with maximally fast decarbonization, the world has only about a 5-50% chance of keeping peak warming below 1.6°C.

“Through rigorous analysis of climate scenarios across eight different models, our research underscores the importance of accounting for the varying capacities of countries as well as regional differences,” said Christoph Bertram, CGS Associate Research Professor and study lead author. “By combining institutional constraints with technological and socio-cultural factors, we show that the most feasible pathways to achieve the Paris climate goals differ from the most widely used cost-effective benchmarks.”

Keywan Riahi, the Director of the Energy, Climate and Environment Program at the International Institute for Applied Systems Analysis (IIASA), added, “From an international fairness perspective this also means that today’s affluent countries and regional alliances like the United States and the European Union not only need to reach their net zero targets, they also need to think about multilateral collaborations to enhance the governance and institutional capacity in vulnerable regions.”

The study integrates region-specific governance indicators to showcase the capacity for implementing climate mitigation policies effectively. This innovative approach builds on past research highlighting the pivotal role of institutional quality in driving successful environmental regulation. The study provides a nuanced framework that can be used in future studies for representing institutional capacity across different regions and over time.

“CMCC’s integrated assessment model WITCH was key to produce the climate mitigation scenarios used in this study,” said Drouet. “For the first time, eight Integrated Assessment Models incorporate a harmonized set of feasibility constraints across geophysical, technological, institutional, socio-cultural, and economic dimensions, while also carefully considering the regional differences in technological and institutional capacities.”

The research underscores the importance of balancing technological advancements with institutional capabilities in formulating effective climate policies. The study’s findings demonstrate that inadequate institutional capacity could hinder reaching even 2°C, whereas improved global institutional support could enhance the likelihood of achieving 1.6°C targets by 25-45%.

Next to improvements in institutional capacity, the study also highlights that reducing overall energy demand and supporting faster electrification accelerates decarbonization toward net-zero and makes it possible to achieve a close to 50% likelihood of limiting peak temperature to 1.6°C.

As efforts intensify towards the 1.5°C goal, it is imperative for global stakeholders to identify pathways that enhance the feasibility of climate actions as well as reduce carbon costs. These findings provide valuable insights for guiding ongoing climate policy discussions and future scenario assessments, thereby supporting informed global climate ambitions and policymaking.

“These new scenarios explore the implications of having many countries that potentially lack the institutional capacity to implement ambitious climate policies,” said Elina Brutschin, Research Scholar at the International Institute for Applied Systems Analysis (IIASA). “Under these conditions, achieving the Paris Agreement goal of keeping temperature rise well below 2°C will be challenging. However, additional strategies such as rapid demand-side transformation, especially in affluent countries, and fast electrification could still make it possible to limit the peak to below 1.7°C.”

“Thanks to the latest advances in low carbon technology deployment such as solar, wind or electric vehicles, the technological feasibility of climate-neutrality is no longer the most crucial issue,” said Gunnar Luderer, lead of the Energy Systems Group at the Potsdam Institute for Climate Impact Research (PIK). “It is much more about how fast climate policy ambition can be ramped up by governments.”

“This research is important because it confronts the complex interaction between technological development and institutional capacities that are required to achieve world climate goals,” said Drouet. “By integrating dynamic governance indicators and analyzing diverse sets of feasibility constraints, the current study improves our knowledge of mitigation pathways for climate. It provides practical insights into the design of climate policy.”

For more information:

Bertram, C., Brutschin, E., Drouet, L. et al. Feasibility of peak temperature targets in light of institutional constraints. Nat. Clim. Chang. (2024). https://doi.org/10.1038/s41558-024-02073-4