我国北方16000年来气候变迁的定量研究

QUANTITATIVE ANALYSIS ON THE CLIMATIC CHAN GES OVER LAST 16000 YEARS IN NORTHERN CHINA

本文通过对两个典型剖面孢粉资料的对应分析,计算出我国北方16000年来温度变化典线。并对温度、湿度变化的过程及两者之间的关系进行了探讨,并对未来气候变化趋向提出了自己的观点。

Temperatures or warmth index (accumulated monthly tempenetures which are 5 degree centjgrete higher)are estimated to use the well dated pol- ien data from Northern China. The pollen data was sampled from sedimend cores section with peat or clay. The technique of correspondence analysis and factor analysis are used in the reconstruction of the climatic changes The analysis suggusts that the climate was much colder and drier during 16000-13000 yea- rs B.PAt that time the summer-half-year temperaturel(SHT) was 10-11 degree centigrede lower than that today. During 13000-11700 years B. P. the clima- te was still cold) (SHT was 8-B. P. 7degree C-lower) but much wet. The clmate in the period of 11700-10000 years was very unstable (changed repidly and frequently). The change range of SHT reached 8-9 degree centigrade and the rate of change was about 4-5 degree centigrade per century. This maybe the characteristic of the transformming period from glacial to interglacial. stage About 10000-9000 years B. P. to 3000 years B. P. SHT had become as high as that at today From 9000 years B. P. to 3000 years B. P. the climate was warmer than that today. The warmest and relative stable climate (optimum) appesred between 8800-5000 years B. P. After 3000 years B. P. climate got cool several cooling occured during Holocene epoch. Their peaks appeared at about 4900 years B. P. 4300 years B. P, 2900 years B. P. and 1800 years B. P.