Tropical rainforests are recognized as one of the terrestrial tipping elements which could have profound impacts on the global climate, once their vegetation has transitioned into savanna or grassland states. While several studies investigated the savannization of, e.g., the Amazon rainforest, few studies considered the influence of fire. Fire is expected to potentially shift the savanna-forest boundary and hence impact the dynamical equilibrium between these two possible vegetation states under changing climate. To investigate the climate-induced hysteresis in pan-tropical forests and the impact of fire under future climate conditions, we employed the Earth system model CM2Mc, which is biophysically coupled to the fire-enabled state-of-the-art dynamic global vegetation model LPJmL. We conducted several simulation experiments where atmospheric CO\(_2\) concentrations increased (impact phase) and decreased from the new state (recovery phase), each with and without enabling wildfires. We find a hysteresis of the biomass and vegetation cover in tropical forest systems, with a strong regional heterogeneity. After biomass loss along increasing atmospheric CO\(_2\) concentrations and accompanied mean surface temperature increase of about 4 \(^\circ \)C (impact phase), the system does not recover completely into its original state on its return path, even though atmospheric CO\(_2\) concentrations return to their original state. While not detecting large-scale tipping points, our results show a climate-induced hysteresis in tropical forest and lagged responses in forest recovery after the climate has returned to its original state. Wildfires slightly widen the climate-induced hysteresis in tropical forests and lead to a lagged response in forest recovery by ca. 30 years.

热带雨林被认为是陆地倾斜元素之一，一旦它们的植被转变为热带稀树草原或草原状态，就可能对全球气候产生深远的影响。虽然有几项研究调查了例如亚马逊雨林的热带草原化，但很少有研究考虑到火灾的影响。预计火灾可能会改变热带稀树草原与森林的边界，从而影响气候变化下这两种可能的植被状态之间的动态平衡。为了研究泛热带森林中气候引起的滞后以及未来气候条件下火灾的影响，我们采用了地球系统模型 CM2Mc，该模型在生物物理上与最先进的火灾动态全球植被模型相耦合LPJmL。我们进行了几次模拟实验，其中大气 CO\(_2\)浓度从新状态开始增加（影响阶段）和减少（恢复阶段），无论是否引发野火。我们发现热带森林系统中生物量和植被覆盖的滞后性，具有很强的区域异质性。在生物量随着大气 CO \(_2\)浓度增加而损失并伴随平均地表温度增加约 4 \(^\circ \) C（撞击阶段）后，系统在返回路径上没有完全恢复到原始状态，即使大气 CO \(_2\)浓度恢复到原来的状态。虽然没有检测到大规模的临界点，但我们的结果显示了热带森林中气候引起的滞后和气候恢复到原始状态后森林恢复的滞后反应。野火略微扩大了热带森林中由气候引起的滞后现象，并导致森林恢复的滞后反应约 30年。