Uncertainty exploration with GCAM
MultiSectoral Dynamic (MSD) models like the Global Change Analysis Model (GCAM) face additional challenges in uncertainty analysis relative to physical system focused modeling. Because GCAM integrates physical and economic representations of land, water, energy, socioeconomics, and climate, by definition, exploring uncertainty in this multisectoral system requires inheriting the uncertainties of the multiple physical systems included. MSD models then additionally must attempt to quantify the uncertainties in socioeconomic futures and the deep uncertainties regarding the interactions of all of these systems. We now have an established literature of modeling these uncertainties with both expertly produced scenarios (SSPs) and exploratory modeling of factorial recombinations of these scenario components. In this presentation, we will provide a survey of many of these studies with GCAM, as well as studies exploring uncertainties due to continuous distributions of key drivers. We will discuss cross-study insights that have emerged. We will close with recent methodological developments opening a new, more efficient perspective on uncertainty analysis for GCAM: emulation-driven analysis.