From emission scenarios to spatially resolved projections with a chain of computationally efficient emulators: coupling of MAGICC (v7.5.1) and MESMER (v0.8.3)

Abstract. Producing targeted climate information at the local scale, including major sources of change projection uncertainty for diverse emissions scenarios, is essential to support mitigation and adaptation efforts. Here, we present first chain computationally efficient Earth system model (ESM) emulators that allow translation any greenhouse gas emission pathway into spatially resolved annual mean temperature anomaly field time series, accounting both forced response natural variability scale. By combining global mean, emissions-driven emulator MAGICC with MESMER, ESM-specific constrained probabilistic emulated ensembles can be derived. This hence build on extend large multi-ESM such as ones produced within sixth phase Coupled Model Intercomparison Project (CMIP6). The main extensions are threefold. (i) A more thorough sampling possible, millions realizations being readily created. (ii) same space sampled pathway, which not case in CMIP6, where only a limited number scenarios have been explored some most societally relevant strong run by small ESMs. (iii) Other lines evidence constrain future projections, observational constraints, introduced, helps refine projected ranges beyond ensembles' estimates. In addition presenting results from coupled MAGICC–MESMER chain, carry out an extensive validation trained applied multiple pathways this study. coupling pave way rapid assessments pathway's regional consequences associated uncertainties.