Climate change policy simulator
C-ROADS is a free, award-winning computer simulator that helps people understand the long-term climate impacts of actions that reduce greenhouse gas emissions. You can use it to rapidly test strategies for tackling climate change.
Select from two versions depending on your intended use:
C-ROADS World Climate
C-ROADS World Climate – NEW!
Suitable for most people, C-ROADS World Climate is designed for our role-play exercise—the World Climate Simulation—and interactive group presentations. It offers global, 3-region, and 6-region modes in order to test national and regional emission reduction policies. Includes French language support (more languages coming soon). C-ROADS World Climate is available for download to Windows and Mac, and runs online.
Designed for technical users looking to analyze specific greenhouse gas emission reduction policies in various forms for up to 15 regions simultaneously. This is the only version of C-ROADS that was available prior to October 2016 and continues to be maintained for technically-oriented policy analysts. Available for Windows and Mac.
- Translates climate mitigation scenarios into emissions, concentrations, temperature, and per-capita emissions outcomes.
- Offers ability to quickly run real-time policy analysis on a laptop or desktop computer, unlike most climate models.
- Backed by a scientific review committee of renowned climate and systems dynamics experts.
- Outputs are consistent with the larger, more disaggregated models used in the IPCC’s AR5.
- Model assumptions, inputs, and methodology are made transparent and in many cases can be easily adjusted to suit the user.
Role of C-ROADS
Since 2008, C-ROADS has helped the world to understand the impact of the emission reduction pledges countries have proposed to the United Nations. These proposals take different forms, with different reference years, reference scenarios, target years, and types of proposals. However, using C-ROADS we can rapidly test these policies and determine whether collectively they are enough to stabilize temperature below 2°C. More complex integrated assessment climate models also have this ability, however, such models can be slow to run and are inaccessible to everyday people. Learn more about the assessments Climate Interactive and MIT have released around the UN climate negotiations and the nationally determined contributions.
To make insights about what it takes to address climate change even more accessible to people, we encourage you to use C-ROADS as part of a World Climate Simulation, where a group of people play the roles of UN climate negotiators working to create an agreement to limit global warming.
C-ROADS was developed by a team from Climate Interactive, MIT, Ventana Systems, UML Climate Change Initiative, and Todd Fincannon. The name C-ROADS stands for “Climate Rapid Overview and Decision Support” simulator.
The model was reviewed by an external scientific review committee, chaired by Sir Robert Watson, former Chair of the Intergovernmental Panel on Climate Change (IPCC). The reviewers recommended C-ROADS for widespread use. Read a summary of their review here.
In 2013 C-ROADS was awarded the System Dynamics Society Award for the best “Real World” Application of System Dynamics.
C-ROADS is being used at top government, corporate, and NGO levels, and by individuals participating in or monitoring the UNFCCC negotiations. Read comments by some of our users at the US State Department and European Environment Agency.
In addition to C-ROADS we have developed several simulations that use the same scientifically reviewed model behind C-ROADS but are in forms that are oriented towards education or focus on particular results that C-ROADS gives us.
- C-Learn, a learning-oriented, three-region version of this simulator, is available online for anyone to use, adapt, extend, and translate into new languages.
- Climate Momentum Simulation is designed to quickly show the dramatic effects that changing CO2 emissions can have on our planet.
- Climate Pathways is an app for iPhones, iPads, and iPods that allows users to guess the emissions trajectories needed to limit global warming to 1.5 or 2 degrees C.
- World Climate is a role-playing game designed for groups of all sizes to experience the dynamics that negotiators face at the UN climate negotiations in coming up with a global climate treaty.
- Frequently Asked Questions (FAQs)
- Comments from C-ROADS users
- Overview of the simulator, 5 pages
- Scientific Review one-page summary
- Technical Reference Guide on the simulator, including simulation purpose, structure, parameters, test results, and bibliography
- Journal article on C-ROADS published in System Dynamics Review July 2012. (translated into Chinese)
- Sterman, John, Thomas Fiddaman, Travis Franck, Andrew Jones, Stephanie McCauley, Philip Rice, Elizabeth Sawin, Lori Siegel. (2013) Management Flight Simulators to Support Climate Negotiations. Environmental Modelling and Software.
- Press coverage of C-ROADS and other Climate Interactive tools
- Webinar on the dynamics behind C-ROADS
A 2 degree scenario in C-ROADS World Climate