Arctic and Tibetan Plateau Tundra Show Divergent Temperature and Precipitation Thresholds Under Climate Change
Huajie Zhu, Han Yu, Hans W. Chen, Ziqian Zhong, Wenzhuo Duan, Songhan Wang, Mousong WuAbstract
The Arctic and Tibetan Plateau (TP) have experienced pronounced warming and shifts in precipitation patterns, yet vegetation responses to climate change remain insufficiently understood. Here, we analyze the temperature and precipitation thresholds of limiting gross primary productivity (GPP) of tundra ecosystems in the Arctic and TP from 1982 to 2100, using a combination of observational data sets and simulations. We found that the temperature thresholds limiting GPP increase in both regions have steadily increased since 1982 and are projected to continue rising. In contrast, precipitation thresholds show significant upward trends in the Arctic but considerable temporal variability in the TP. By 2100, precipitation limitation of GPP is projected to exert a stronger influence in browning zones than in greening zones, whereas temperature limitation is more pronounced in greening zones. Our results reveal the diverse vegetation responses to temperature and precipitation in the Arctic and TP tundra.