The Impact Benefits Calculator (IBC)

The Impact Benefits Calculator (IBC) is a tool integrated into LEAP that translates emissions scenarios into estimates of health and climate impacts. It utilizes parameterized results from the GEOS-Chem Adjoint model and standard concentration-response functions to calculate population-weighted PM2.5 concentrations and associated premature mortality. The tool is designed to be accessible to planners in the developing world, reducing complex modeling that previously required supercomputers to calculations that run in seconds. It currently supports 161 countries and analyzes pollutants including CO2, methane, black carbon, and nitrogen oxides.

• The IBC estimates health and climate impacts by combining LEAP emissions scenarios with parameterized results from the GEOS-Chem Adjoint global 3D chemical transport model to determine population-weighted concentrations of fine particulate matter (PM2.5).
• To function, the IBC requires comprehensive emissions inventories and scenarios for various pollutants, including CO2, methane (CH4), black carbon, organic carbon, PM2.5, non-methane volatile organic compounds (NMVOCs), nitrogen oxides (NOx), sulfur dioxide (SO2), and ammonia (NH3).
• The tool incorporates global emissions data for the period 2010-2050 from the IIASA ECLIPSE scenarios, offering both a baseline scenario with minor worldwide efforts and a maximal effort scenario involving 16 measures, such as banning agricultural residue burning.
• The IBC increases accessibility for planners in the developing world by parameterizing GEOS-Chem Adjoint calculations, which reduces processing time from several days on supercomputers to a few seconds within LEAP.
• The IBC has been calibrated for use in 161 countries and was developed through a collaboration between the Stockholm Environment Institute and the University of Colorado, with support from UNEP and the Climate and Clean Air Coalition (CCAC).

APA

Stockholm Environment Institute (n.d.). The Impact Benefits Calculator (IBC). https://leap.sei.org/help24/IBC/Introduction_to_IBC.htm

Chicago

Stockholm Environment Institute. The Impact Benefits Calculator (IBC). n.d. https://leap.sei.org/help24/IBC/Introduction_to_IBC.htm.

Wikipedia

{{cite report |author=Stockholm Environment Institute |title=The Impact Benefits Calculator (IBC) |url=https://leap.sei.org/help24/IBC/Introduction_to_IBC.htm |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{stockholmenvironmentinstitutendimpact, author = {{Stockholm Environment Institute}}, title = {{The Impact Benefits Calculator (IBC)}}, institution = {Stockholm Environment Institute}, url = {https://leap.sei.org/help24/IBC/Introduction_to_IBC.htm}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }