Simulated warm periods of climate over China during the last two millennia: The Sui‐Tang warm period versus the Song‐Yuan warm period

Abstract

A 2000 year simulation forced by the external forcings of the last two millennia is carried out with the Community Earth System Model. We compare climate changes over China between the peak Sui-Tang warm period (Sui-TangWP; 650-700 A.D.) and Song-Yuan warm period (Song-YuanWP; 950-1000 A.D.), which were two key culturally, economically, and educationally prosperous eras in Chinese history. The simulation indicates warm conditions in both periods, but the warmth is mainly seen in East China in the peak Sui-TangWP, and over the whole of China in the peak Song-YuanWP. The warming in the peak Sui-TangWP is attributed to the localized increase of atmospheric net energy with favorable heat transport, whereas the peak Song-YuanWP results from the increase of global solar radiation. The annual mean precipitation anomalies in the peak Sui-TangWP exhibit a meridional dipole pattern over East China, with enhanced precipitation in the region south of the Yangtze River and decreased precipitation to the north. In the peak Song-YuanWP, the precipitation enhances over most parts of China. The precipitation anomalies are largely attributed to the water vapor transport anomalies associated with monsoon circulation changes. The simulated climate changes are broadly consistent with reconstructions, but the magnitude is greatly underestimated. Based on the simulation and reconstructions, we suggest that the Sui-TangWP may have been a regional phenomenon in China, while the Song-YuanWP was a reflection of global/hemispheric-scale warm events that took place at the same time.

Precipitation variation over eastern China and arid central Asia during the past millennium and its possible mechanism: Perspectives from PMIP3 experiments

“…In particular, Man et al [] suggested a stronger EASM and a north‐flood and south‐drought pattern over eastern China during the MCA based on Max‐Planck‐Institut (MPI) model results, whereas precipitation is enhanced (suppressed) in summer over the whole of eastern China in ECHO‐G simulations [ Liu et al , ]. However, Yan et al [] found drier conditions in North China from 950 to 1000 A.D. in a Community Earth System Model model simulation. In addition, based on Community Climate System Model version 2.0 (CCSM2.0) model results, Peng et al [] indicated that several severe droughts had occurred over eastern China in the past millennium, which were associated with a weakened EASM.…”

Detection and attribution of summer temperature changes in China during the last millennium

“…All individual simulations show warmer temperatures in the MCA and cooler in the LIA (Figure 4, with reference to the period of 1401–1850 AD), consistent with that of the reconstruction. The results agreed with previous studies based on the model simulations, which showed warmth conditions in the peak MCA (Yan et al ., 2015) and cold conditions in the LIA (Zhou et al ., 2019) over the whole of China. However, the performance differences are more remarkable for the simulations than the reconstruction over the MCA (Figure 6a).…”

Biogeochemical evidence for environmental and vegetation changes in peatlands from the middle Yangtze river catchment during the medieval warm period and little ice Age

“…North-south differences in the environment (northern drought and humid south) encouraged invaders from Mongolia to move toward southern China and compete for resources. Migration contributed to the population of Jiang Xi Province (Nan Chang County Annals) and lasted until the Yuan Dynasty (1271-1368 AD) when the southern China experienced a warm period (Yan et al, 2015). The warm and humid climate in the middle Yangtze River catchment encouraged population development.…”