Abstract: Once climate change brings various stresses and disturbances on the receptor system, the receptor system will transfer these stresses and disturbances to other systems through its connection with them, resulting in the continuous extension of climate change effects in time and space, forming a complex climate change impact chain. At present, studies on the impacts of climate change mostly focus on the direct impacts, while the indirect impacts are rarely considered. The incomplete understanding of the impact transmission of climate change is one of the main constraints in addressing climate change. It is of great significance to explore the formation mechanism of the impact chain of climate change. This research analyzed the characteristics of climate change impacts, explored the formation mechanism of climate change impact chains, defined the connotation and classification of climate change impact chains, clarified the impact levels of climate change, and proposed ways to cope with climate change impact chains. The results showed that the impacts of climate change were extensive, different, persistent, transferable, transformable, and sometime sudden. When climate change acted on the direct receptors, the impacts of climate change would be transmitted along the food chain in the ecosystem, along the industrial chain in the economic system, and along the social relationship chain in the social system. The transmission of impact chain took the form of material flow, energy flow and information flow. The impacts of climate change always rose from low to high levels, along changes in resource endowments to natural production, economic production systems and social systems. It is believed that the effective control or cutting off of the transmission of adverse impacts of climate change can effectively reduce the impact risks and losses of climate change. The impact chain of climate change and its formation mechanism provide ideas and approaches for people to deal with climate change comprehensively.

Key words: Climate change impact chain, Formation mechanism, Connotation, Classification, Impact hierarchy, Climate change response