Transient vegetation degradation reinforced rapid climate change (RCC) events during the Holocene

High-resolution multi-proxies from geological archives have revealed a series of rapid climate change (RCC) events during the Holocene. These events coincided with the so-called "Bond events", which were previously linked to a weakened thermohaline circulation. However, the proposed atmosphere–ocean teleconnections associated with these events are regionally distinct, which explains why most previous studies have only explained a subset of the RCC events, depending on region and proxy type; moreover, the suggested mechanisms are much debated. Here, we present a major effort of Holocene transient simulations that identify a series of centennial-scale RCC events that are consistent with records from geological archives. All eight Holocene RCC events were captured in North China (NC) and pervasive throughout the Northern Hemisphere (NH) in experiments with active dynamic vegetation modules (DV), whereas they were largely absent in experiments without DV. These results suggest that the collapse of the terrestrial vegetation and the resulting feedback played a crucial role in RCC events. Our findings supplement or even challenge the notion that North Atlantic cooling, closely linked to ice-rafted debris (IRD) events, was the dominant driver of RCC events.

Xinzhou Li, Xiaodong Liu, Zaitao Pan, Zhengguo Shi, Xiaoning Xie, Hongyan Ma, Jizhou Zhai, Heng Liu, Xiaoxun Xie, Aona Dai