Convection Permitting Regional Paleoclimate Simulations with Climate-Driven Land-Use Mapping for a reduced Mediterranean domain

The Central Mediterranean's complex topography and dynamic land-sea interactions provide a compelling opportunity for high-resolution paleoclimate modelling aimed at enhancing our understanding of natural climate variability. This study utilizes the RegCM5 regional climate model to conduct km-scale simulations, focusing on fine-scale climate dynamics for a reduced Mediterranean domain across five pivotal paleoclimate periods: Modern (ca. 1995 CE), Pre-Industrial (ca. 1850 CE), Medieval Climate Anomaly (MCA, ca. 1000 CE), mid-Holocene (6000 BP), and Last Glacial Maximum (LGM, 21000 BP). Simulations are driven by MPI-ESM-LR model outputs from PMIP4, with ERA5 reanalysis data used for evaluation runs.

A novel land-use mapping technique is applied, leveraging Köppen-Geiger climate classifications and current vegetation distributions to reconstruct paleoclimate vegetation patterns. Simulation results are benchmarked against E-OBS, ModE-RA, MCruns, and lgmDAnomaly datasets, revealing typical biases. Historical data exhibits a cold bias, while the 6000 BP period shows scattered low-level wet and cold biases, and the 21000 BP period presents warm and wet biases. Despite these challenges, the km-scale simulations effectively capture detailed climatic patterns, providing crucial insights into the Mediterranean’s paleoclimate and regional implications. These findings highlight the value of downscaling global models to km scales, which can advance our understanding of past climate dynamics and informing strategies for future climate adaptation.