C-LEARN

The launch version of the Climate Collaboratorium uses a single climate model, C-LEARN. C-LEARN is a Web-based version of C-ROADS, a simulation of Sustainability Institute and Ventana Systems that is part of the Climate Interactive effort.

In the Collaboratorium, C-LEARN is the primary climate model. It takes greenhouse gas emission and deforestation/aforestation targets as inputs and provides outputs such as atmospheric concentrations of carbon dioxide (CO2) and increase in global mean temperature (GMT).

Overview

Name C-LEARN
Brief description C-LEARN is a simplified, Web-accessible version of the Climate Rapid Overview and Decision Support Simulator (CROADS), which is designed for use by policy makers to enable real time assessment of proposals under consideration as a part of the United Nations Framework Convention on Climate Change process.
Model developer(s) Tom Fiddaman, Lori S. Siegel, Elizabeth Sawin, Andrew P. Jones, John Sterman
Institutional affiliation of developer(s) Sustainability Institute, Ventana Systems, and System Dynamics Group, MIT Sloan School of Management
Date created 2008
Date of most recent revision 2009
Model accessibility C-LEARN is available on the Web at http://forio.com/simulation/climate-development/index.htm. C-ROADS can be run on a personal computer using VenSim, a simulation application developed by Ventana Systems. At present the C-ROADS model is used solely in workshops and events moderated by members of the Climate Interactive team.
Documentation Tom Fiddaman, Lori S. Siegel, Elizabeth Sawin, Andrew P. Jones, and John Sterman. C-ROADS Simulator Reference Guide. January, 2009.
Key publications Robert Watson, Eric Beinhocker, Bert de Vries, Klaus Hasselmann, David Lane, Jorgen Randers, Stephen Schneider. Summary Statement from the C‐ROADS Scientific Review Panel. February 2009 (see here for a brief description of the scientific review process and its findings).
Elizabeth R. Sawin, Andrew P. Jones, Tom Fiddaman, Lori S. Siegel, Diana Wright, Travis Franck, Andreas Barkman, Tom Cummings, Felicitas von Peter, Jacqueline McGlade, Robert W. Corell, and John Sterman. Current Emissions Reductions Proposals in the Lead-Up to COP-15 are Likely to be Insufficient to Stabilize Atmospheric CO2 Levels: Using C-ROADS—A Simple Computer Simulation of Climate Change—To Support Long-Term Climate Policy. Climate Change—Global Risks, Challenges, and Decisions Conference, University of Copenhagen. March 2009.

Model attributes

Model type Quick running climate model (get exact text from scientific review)
Geographic scope Global
Geographic resolution 3 regions or emission reduction targets, global for deforestation/aforestation targets
Start date 1850
End date 2100
Time step 0.25 year
Approach for addressing risk/uncertainty Model outputs to not show level of uncertainty associated with simulation
Data sources

Country-level CO2 emissions from fossil fuels from Global, Regional, and National Fossil Fuel CO2 Emissions. Carbon Dioxide Information Analysis Center (CDIAC), Oak Ridge National Laboratory, U.S. Department of Energy.
CO2 emissions from changes in land use from Carbon Flux to the Atmosphere from Land-Use Changes 1850-2005 Carbon Dioxide Information Analysis Center (CDIAC), Oak Ridge National Laboratory, U.S. Department of Energy.
GDP and population from Statistics on World Population, GDP and Per Capita GDP, 1-2006 AD Conference Board and Groningen Growth and Development Centre, Total Economy Database.
Business As Usual CO2 emissions projections are calibrated to the scenarios in the IPCC's Special Report on Emissions Scenarios (SRES), with the International Energy Agency (IEA)’s World Energy Outlook 2007 allocations between regions. The C-LEARN default BAU scenario is the IPCC's A1F1 scenario. For an overview of the IPCC scenarios, see "What is the range of GHG emissions in the SRES scenarios and how do they relate to driving forces?" in Summary for Policy Makers section of the SRES.
Population and GDP projections are based on the United Nations’ World Population Prospects 2004 forecast and U.S. Energy Information Agency (EIA)'s International Energy Outlook 2008 GDP forecast, respectively.

Key modules and linkages between them
C-LEARN/C-ROADS is comprised of six sub-models:

Regional CO2 emissions
Other greenhouse gasses (CH4 and N2O)
Land use
Carbon cycle
Global Average Surface Temperature
Sea level rise

Model diagram