Abstract:

Studies of historical climate and environment changes in the eastern monsoonal region of China have made great progress in recent years. However, progressively studies indicate that the processes of climate and environment changes during the last 2000 years differed greatly in different regions. This is especially the case among studies based only on single-site records, possibly because of different materials, proxy indicators, dating accuracy, etc. Therefore, it is necessary to conduct comprehensive and integrated analyses of regional climate and environment changes at larger spatial scales. Here, multiple climate proxy records selected from 16 sites in southeastern China (i.e., approximately east of 105° E and south of 30° N) were used to synthesize and reconstruct the temperature and precipitation changes over the past 2000 years, and the possible forcing mechanisms behind these changes were explored. The results indicate that the integrated temperature sequence in the study region is quite comparable to the reconstructions for the entirety of China, eastern China, and the Northern Hemisphere. Several typical characteristic climate periods on centennial timescales, such as the Dark Age Cold Period, the Medieval Warm Period, the Little Ice Age, and the modern warm period of the 20th century, were well revealed in the present reconstruction. The integrated precipitation sequence shows that the dry and wet phases in southeastern China have changed significantly during the past 2000 years. Specifically, precipitation was relatively higher during the Medieval Warm Period, but it was relatively lower during the Little Ice Age (i.e., less precipitation occurred in the former part of the Little Ice Age and more precipitation occurred during the latter part). In general, the synthesized temperature and precipitation changes in southeastern China had relatively diverse hydrothermal combinations during the last 2000 years. However, it is noteworthy that the integrated precipitation sequence in southeastern China is weakly comparable to the sequence in northern China, reflecting great regional differences in historical precipitation changes. Thus, the forcing mechanisms might differ greatly from south to north in the monsoonal region of eastern China. Furthermore, the results suggest that large-scale atmosphere–ocean interactions, volcanic activities, and changes in solar radiation could have had significant effects on the climate and environment changes in southeastern China during the last 2000 years.

Key words: climate change, integrated reconstruction, historical period, forcing mechanism, Southeastern China