Fig. 1: Data and model comparison of EASM precipitation during the MPWP.

Left panel: pre-industrial (PI) mean June-July-August (JJA) of three variables (from top to bottom: a precipitation (P), b evaporation (E), c precipitation minus evaporation (P-E); units: mm/day) derived from the PlioMIP2 multi-model ensemble (MME); right panel: as left panel but for differences of three variables between mid-Piacenzian Warm Period (MPWP) and PI (d–f). Black dotted areas in the right panel indicate agreement of the MME with regard to precipitation anomaly, MPWP vs. PI (at least 10 out of 14 models show the same sign of precipitation change as the MME). Towards a quantitative data–model comparison the same color bar is used for recorded (colored circles; 25 pollen-based precipitation records, shown in the δP anomaly MPWP-PI) and simulated precipitation changes. According to the definition of ref. 21, the EASM domain is calculated separately for PI (black “+” symbol, left panel) and MPWP periods (colored “+” symbols, divided into three categories: common areas for both periods (gray “+”, right panel), expanding/shrinking areas during the MPWP relative to PI disentangled by different colors (blue/yellow “+”, right panel)). Black and yellow curves denote the coastlines of PI (left panel) and MPWP (right panel), respectively.