A couple of years ago, before the adoption of Ireland's carbon budget programme and the allocation of the sectoral emissions ceilings I was thinking about what combination of sub-targets for the transport sector would translate into a 50% reduction in emissions from 2018 levels.
In 2018 the emissions from the transport sector were approximately 12 MtCO2 equivalent. Therefore a 50% reduction would see absolute emissions of around 6 Mt CO2 eq. I created an R shiny app to try to understand what various mode shares, electrification percentages, efficiency improvements and avoided demand levels would translate to in terms of emissions output.
The code for this was written in R using RStudio and is available on my GitHub here.