Long-distance modern analogues bias results of pollen-based precipitation reconstructions

Timing of the precipitation optimum in the Holocene for the semi-arid northern China affects our understanding of the tempo-ral-patterns of the East Asian Summer Monsoon and its connection with precipitation in the monsoon fringe area.Discrepancies about when this occurs(early Holocene or mid-Holocene)exist in paleo-climate records based on various proxies and models.What causes these discrepancies is still a hot topic[1].