As the world confronts the catastrophic risks of surpassing 2°C of warming, tools like En‑ROADS—a global climate simulator that lets users test the impact of climate policies in real time—offer a powerful way to turn data into practical policy decisions. Researchers from Nottingham Trent University’s Department of Engineering demonstrate how such tools can guide more informed, collaborative and effective climate action.

If global temperatures rise beyond 2°C, the consequences for ecosystems and human societies will be catastrophic. We could witness severe disruptions including increased frequency and intensity of extreme weather events such as hurricanes, droughts, floods and heatwaves, leading to significant loss of life and economic devastation. Rising sea levels could displace millions of people living in coastal areas, creating unprecedented humanitarian crises and increased migration pressures. Ecosystems could suffer irreversible damage, with biodiversity loss accelerating as many species struggle to adapt to rapidly changing climates. Agricultural productivity may sharply decline, leading to widespread food insecurity, malnutrition and increased poverty. Additionally, water scarcity could intensify, exacerbating conflicts over limited natural resources and threatening global stability.

Climate predictions and simulated impacts

Climate predictions, including those from En-ROADS, are typically generated using integrated assessment models (IAMs), which combine data from climate science, economics and energy systems. These models simulate how policy decisions, technological change and societal behaviour influence emissions and global temperature over time. There is strong consensus among scientists that such models, while simplifications, are essential tools for understanding likely climate futures. For instance, the Dynamic Integrated model of Climate and the Economy (DICE) and the Regional Integrated model of Climate and the Economy (RICE) are widely used IAMs that assess the economic impacts of climate change and mitigation strategies. Additionally, the Global Change Assessment Model (GCAM) integrates energy, water, agriculture and land use systems to explore climate policies. These models, among others, contribute to a comprehensive understanding of climate dynamics and inform policy decisions beyond the scope of IPCC assessments.

Our project, the En-ROADS Climate Solutions Simulator, draws on insights from MIT Sloan’s work with the aim of helping investors to quantify climate risks and opportunities, emphasising the simulator’s role in aligning financial decision-making with sustainability goals. En-ROADS uses a system dynamics model developed by Climate Interactive and MIT Sloan, drawing from peer-reviewed data and calibrated against the best available science to provide accessible, policy-relevant insights.

The simulator reflects a broad scientific consensus by incorporating relationships between global policies, economic trends, and environmental responses. It simplifies complex dynamics into an accessible format, allowing users to see how changes in areas like carbon pricing or energy efficiency affect long-term temperature outcomes. Current projections from En-ROADS (Figure below) suggest a potential rise of 3.3°C by 2100 under baseline scenarios. This scenario assumes that no new significant mitigation policies are introduced beyond those already in place. This stark reality underscores the urgency of adopting evidence-based climate interventions.  The figure illustrates how current levels of action across sectors such as energy, transportation, agriculture, and carbon removal remain insufficient to meet the targets of the Paris Agreement.

Simulation as a catalyst for change

For years, discussions on climate action have often been limited to theoretical frameworks, leaving decision-makers overwhelmed by the complexity of potential interventions. For instance, global initiatives like the UNFCCC Nationally Determined Contributions (NDCs) often present ambitious goals without clear implementation roadmaps, making it difficult for policymakers to translate them into tangible actions. Similarly, traditional integrated assessment models used in climate economics can be opaque and inaccessible to non-specialists, limiting their practical use in real-time policy design.

Traditional academic models are often static and complex, and there is a need for more dynamic, intuitive and accessible ways of understanding the adverse impacts of global warming.

En-ROADS changes this narrative by making climate solutions tangible and actionable. It allows users to simulate real-world policies in a virtual environment, offering immediate feedback on their potential impacts. Traditional academic models are often static and complex, and there is a need for more dynamic, intuitive and accessible ways of understanding the adverse impacts of global warming. For that reason, En-ROADS has a user-friendly interface that enables policymakers, business leaders and educators to experiment with different combinations of interventions. Users can test the effects of combining renewable energy subsidies with carbon pricing or explore how electrification impacts global emissions. The visual results make it easy to grasp the effectiveness of each policy, fostering a deeper understanding of the trade-offs and synergies involved.

Key insights on renewables, carbon and agriculture

Our research demonstrates how various policy interventions influence global temperature trajectories. For instance, electrification of sectors, when paired with renewable energy adoption, can reduce temperature rise by 0.6°C. Carbon pricing contributes an additional 0.4°C reduction, while reforestation and carbon removal technologies collectively reduce temperatures by 0.3°C. These results highlight the compounded effectiveness of integrated strategies in achieving climate goals.

Our simulations also underscore critical trade-offs. For example, while renewable energy subsidies drive down emissions, they require significant upfront investments and political commitment. Similarly, carbon taxes face resistance from stakeholders but are among the most effective tools for systemic change. Secondly, for carbon pricing, taxes on fossil fuels create economic incentives for cleaner alternatives. Scenarios modelled in En-ROADS showed a reduction of 0.4°C, with the caveat of potential political resistance. Effective policy design can mitigate opposition.

Thirdly, for renewable energy subsidies, these can make renewables economically competitive, driving widespread adoption. Denmark’s success in wind energy, reflected in our En-ROADS simulations, demonstrates how bold investments can transform energy landscapes. For example, Denmark’s heavy wind energy subsidies have enabled it to meet 47 per cent of its electricity needs through wind power as of 2021. For carbon removal solutions, technologies like bioenergy with carbon capture and reforestation play crucial roles in offsetting emissions. Simulated impacts highlighted a reduction of up to 0.3°C from reforestation alone, emphasising the importance of integrating nature-based solutions. For instance, projects like the Bonn Challenge have successfully restored over 210 million hectares of degraded land globally, reinforcing the viability of large-scale reforestation efforts.

Finally, for agricultural emission reductions, sustainable farming practices, when modelled, showed modest reductions in temperature rise but significant co-benefits, including biodiversity preservation. For example, New Zealand’s investment in methane-reducing livestock feed technologies demonstrates how innovative agricultural strategies can contribute to emissions reduction.

Turning simulations into action

Data alone is not enough to drive change; it’s the actions informed by that data that make a difference. By using the simulator, we’ve been able to translate complex climate challenges into specific, actionable steps that stakeholders can adopt. For example, policymakers can prioritise electrification and carbon pricing based on clear evidence of their effectiveness, while businesses can explore targeted investments in renewables.

One of the key strengths of En-ROADS is its ability to foster collaborative decision-making. In workshops, participants explore scenarios together, weigh the pros and cons of different interventions, and align on strategies that can be implemented in real-world contexts. These sessions have shown that when people see the impact of their choices in real time, they are more likely to take ownership of the solutions.

En-ROADS has been used by the UN Global Compact, the U.S. State Department and hundreds of educators worldwide.

It is also valuable in educational and advocacy settings. By presenting climate strategies in a visual and interactive way, En-ROADS breaks down the complexity of climate science into understandable concepts. This approach equips individuals with the knowledge and confidence needed to advocate for policies or take action in their own communities. For example, En-ROADS has been used by the UN Global Compact, the U.S. State Department and hundreds of educators worldwide to facilitate climate literacy and informed decision-making. These sessions have shown that when participants visualise policy outcomes in real time, they are more confident and motivated to advocate for effective climate policies or launch initiatives in their local communities.

The En-ROADS simulator exemplifies how innovative tools can bridge the gap between data and action. By empowering individuals, organisations and governments to visualise the impacts of their decisions, it fosters a culture of informed decision-making. As the global community faces the climate challenge, tools like these illustrate that collaborative action and bold policies can pave the way to a sustainable future.