Carbon Debt Explorer
An interactive dashboard showing how regional carbon debt shifts with the equity assumptions behind it
The Carbon Debt Explorer is a browser-based dashboard that distributes a remaining global carbon budget across the ten IAMC R10 regions and compares each region's fair share against its cumulative emissions, historical and projected. The comparison yields a single number per region: carbon debt, defined as cumulative emissions minus the fair-share allocation. A positive value is an overdraft on the budget; a negative value is credit. The accounting framework is the one set out in our net-zero carbon debt paper (Pelz et al., PNAS 2025).
The debt number depends on the equity assumptions behind it. Users choose the temperature goal (1.5C at 50%, 2C at 66% or 90%, with budgets from Lamboll et al. 2023), the first year from which historical emissions count (1900 through 2023), the future emissions pathway (NDCs and pledges, or current policies, from REMIND-MAgPIE R10 aggregates), and whether per-capita shares are adjusted for capability using GDP. Changing any of these shifts the numbers, sometimes substantially, and the dashboard is built so those shifts are visible rather than buried in a methods appendix.
It was built in 2024 as an R Shiny app to support stakeholder engagement within the ELEVATE project, and has since been rebuilt as a static site whose allocation mathematics come from the fair-shares library, so the numbers stay in sync with that codebase. It is preserved as a legacy tool rather than actively extended; new allocation work belongs in fair-shares directly.