Using Different IBC Methods in Different Scenarios

Use the IBC tab of the Settings screen to set default methods for (1) calculating health impacts as a function of exposure and (2) setting the approach used for scaling base year particulate matter emissions.

If you want to compare the results due to these different methods you can create additional scenarios in which you vary these methods. Do this as follows:

1. Health Impact Relative Risk Function

To control which function is used, create the following Key Assumption Branch: Key\IBC Settings\Relative Risk Version. Note that "IBC Settings" is itself a category branch. Within that branch, specify an integer version number to control which function should be used. The value can vary by scenario. The currently supported values are:

0: Global Burden of Disease 2010 (Burnett et al, 2014)

1: Global Burden of Disease 2015 (Cohen et al, 2017 - coming soon)

If the above branch is not defined or if you specify any value outside the supported range of values then LEAP will use the default method specified on the IBC tab of the Settings screen.

2. Base Year Particulate Matter Scaling

To control which approach is used, create the following Key Assumption Branch: Key\IBC Settings\PM Scaling. Within that branch specify an integer version number to control which approach should be used. The currently supported values are:

0: No Scaling
Base year and future concentrations calculated directly from base year LEAP emissions. Supports any base year. Can also be used if LEAP model contains only a partial accounting for relevant national particulate-forming emissions.

1: Scaling using the approach described in van Donkelaar, 2016.

Notes: Base year concentrations based on satellite-based estimates. LEAP emissions only used to calculate future changes in concentrations. Requires LEAP base year to be set to 2010. Also requires complete accounting for all relevant particulate-forming national emissions.

2: Scaling using the approach described in Shaddick, 2018.

If the above branch is not defined or if you specify any value outside the supported range of values then LEAP will use the default method specified on the IBC tab of the Settings screen.