中国过去3ka冷暖千年周期变化的自然证据及其集成分析

WARM-COLD CHANGE IN MILLENARIAN CYCLE DERIVED FROM NATURAL PROXY DATA IN CHINA DURING THE PAST 3000 YEARS

基于集成分析的思想 ,对不同时间分辨率的自然信息所反映的过去 3ka我国冷暖变化进行综合分析 ,划分了百年尺度上过去 3ka冷暖变化的阶段 ,进而发现冷暖变化呈现 1.3～ 1 35ka的重现周期 ,每个周期包含相继出现的 4冷暖阶段 :持续 30 0～ 35 0a的暖期、5 5 0～ 6 0 0a的冷期、2 0 0～ 2 5 0a的暖期和 2 0 0a左右的冷期。每个冷暖期中发生的相对冷暖事件也服从 1.3～ 1.35ka周期。在冷暖变化幅度上 ,30 0～ 35 0a的暖期较 2 0 0～ 2 5 0a的暖期显著 ,5 5 0～ 6 0 0a的冷期较 2 0 0a左右的冷期显著。目前处在长度为 2 0 0～ 2 5 0a的暖期中 ,其特点可以与 2 .7～ 2 .5kaBP和 1.4 0～ 1.15kaBP的暖期相类比。

The concept of the IGBP synthesis is used to analysis the natural proxy data indicated past 3000 years warm-cold changes in China. The proxy data used in this paper are collected from the articles published in recent 20 years which are able to clearly indicate cold/warm changes, fairly dating, and less effected by human activities. The warm-cold change during the past 3000 years is reconstructed following steps. First, to identify the major cold stages preliminarily based the advances of glaciers in western China and the periglacial phenomenon in northern China. Second, to divide the warm-cold stages in additional evidence of paleosol from the regions sensitive to temperature change. Third, to accurate the division of warm-cold stages and to identify the warm or cold events in each stage based on the series of pollen, ice core, annual laminae gray level variations of stalagmite, treering, limatological records. It is found that, ①the warm-cold change reoccurs in a 1.3～1.35 ka period; Each period includes 4 stages: 300～350 a warm stage, 550～600 a cold stage, 200～250 a warm stage, and about 200 a cold stage. ②cold or warm events in each stage reoccurred in the 1.3～1.35 ka period too. ③The warm in the 300～350 a length warm stages is more sensitive than that in the 200～250 a length warm stages; the cold in the 550～600 a length cold stages is more sensitive than that in the about 200 a length cold stages. ④ Now is in a 200～250 a length warm stage started from the beginning of the 20th Century. The warm stages of 2.7～2.5 ka BP and 1.4～1.15 ka BP many be its historical analogies.