RECONSTRUCTION AND ANALYSIS ON THE SERIES OF WINTER-HALF-YEAR TEMPERATURE CHANGES OVER THE PAST 2 000 YEARS IN EASTERN CHINA
GE Quan-sheng 1, ZHENG Jing-yun 1, MAN Zhi-min 2 , FANG Xiu-qi 3,1 , ZHANG Pi-yuan 1 (1.Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; 2.Institute of Chinese History a
The quantitative series of the winter-half-year temperature in eastern China over the past 2000 years in 10～30 year resolution is reconstructed by phenomena records and the other proxy data with cold/warm description extracted from Chinese historical documents, some cold/warm time series in China published in last couple of decades, and the instrumental data from 1951—1999. The variability and amplitudes of cold-warm changes in eastern China during the past 2 000 years are discussed as well. In summary, the winter-half-year temperature changes over the past 2000 years in eastern China can be outlined as follows:(1) From the beginning of Christian era, the climate tended to decrease in fluctuation with the cooling rate of 0.17℃/100a, and around 490s the temperature decreased to the lowest of the first epoch, about 1.0℃ lower than that of 1951—1980.(2) Then the temperature rose rapidly and entered the warm epoch of 570s—1310s. In this epoch,the climates were dominantly warm, and the temperature rose slowly in fluctuation. The 30-year mean temperatures of two warm peaks were generally 0.3～0.6℃ higher than that of 1951—1980, and once reached the highest of over 0.9℃. For the cold troughs between the two warm peaks, the 30-year mean temperatures were generally 0.5～0.7℃ lower than that of 1951—1980.(3) After 1310s, the temperature descended rapidly. The 30-year mean temperatures of the four cold troughs were generally 0.6～0.9℃ lower than that of 1951—1980 with the minimal of 1.1℃. For the relative warm peaks between the cold troughs, the 30-year mean temperatures were slightly higher than that of 1951—1980.(4) Since then, the temperature has been rising rapidly and entered the warm epoch of the 20th Century. For the most recent two decades, the temperature increases dramatically. The mean temperature from 1981 to 1999 is 0.5℃ higher than that from 1951 to 1980.(5) The winter-half-year temperature changes over the past 2000 years indicate that the transition between cold period and warm period is usually characterized by rapidity. For example, during the warming from the cold epoch to the warm epoch between the 5th and 6th Century (480s—500s to 570s—590s), the temperature increased by 1.3℃ within 90 years. So as the cooling from the warm epoch to the cold epoch between the 13th and 14th Century (1260s—1280s to 1320s—1340s), the temperature decreased by 1.4℃ within 90 years. During the mid- and late- 19th and the early 20th Century (1860s—1880s to 1920s—1940s), the temperature increased by 1.0℃ within 60 years. Since the mid- and late-19th Century to present (1860s—1880s to 1980s—1990s), the temperature has risen by 1.5℃ within 110 years, particularly the temperature increased by 0.5℃ from 1981 to 1999 AD.