从古里雅冰芯与祁连山树轮记录看过去2000年气候变化  

COMPARATIVE STUDY OF THE CLIMATE CHANGES IN THE PAST 2 000 YEARS BY USING ICE CORE AND TREE RING RECORDS

作　　者：姚檀栋[1] 杨梅学[1] 康兴成[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所,兰州730000

出　　处：《第四纪研究》2001年第6期514-519,共6页Quaternary Sciences

基　　金：国家重点基础研究发展规划项目 (批准号 :G1 9980 4 0 80 0 );中国科学院资源环境领域知识创新工程重大方向项目(批准号 :KZCX2 -30 1 )资助

摘　　要：本文通过对青藏高原上所钻取的古里雅冰芯和青海都兰树轮高分辨率气候变化记录的对比 ,分析了过去近 2 0 0 0a来的气候变化特征。结果表明 :1 )这两个地区过去 2 0 0 0a来温度都在波动中逐渐上升 ,展示了气候逐渐变暖的趋势。进入 2 0世纪以来 ,气候显著变暖 ,并有加速变暖的趋势 ;2 )树轮和冰芯均明显地记录了小冰期的 3次冷期 ,其出现的时间基本上一致。小冰期并不是过去 2 0 0 0a来的最寒冷的时期。冰芯和树轮记录均表明公元初的寒冷程度要大于小冰期 ;3 )古里雅冰芯所记录的温度和降水量揭示出 ,过去近 2 0 0 0a来的降水和温度变化的总趋势是正相关关系 ;但在短时间尺度上 ,温度和降水的变化并不同步。这主要表现在两个方面 ,一是温度长期变化中的低频波动频率要大于降水 ,二是虽然温度和降水的变化在百年级时间尺度上有正相关性 ,但降水的变化要滞后于温度变化 5 0～ 1 0 0a;4)同时周期分析表明 ,古里雅冰芯中的δ18O和积累量以及都兰树轮记录的变化周期大多数与太阳活动有关 ,表明青藏高原地区冷、暖、干、湿变化的主要驱动力可能是太阳活动的变化 ;5 )对这两记录的对比研究也揭示了气候变化的区域差异。如中世纪暖期在都兰树轮记录中很强而在古里雅冰芯记录中很弱 ,而都兰树轮记录中 。In this paper, the features of the climate changes since 2 000a B.P. were examined by comparing the high-resolution records of the Guliya ice core and the Dulan tree ring. The results show the temperature has been increasing with fluctuations since 2 000a B.P.. This is especially true since the beginning of the 20 th century. There were 3 cold periods in the Little Ice Age, which are recorded by the Guliya ice core and the Dulan tree ring. The ice core and the tree ring show that the LIA is not the coldest period in the past 2 000 years. They demonstrated the early century was colder than the LIA. The temperature (δ 18O) and precipitation (net accumulation) recorded in the Guliya ice core show that the temperature fluctuations is positively correlated to the precipitation on a long time scale. However, the temperature and precipitation fluctuations are not synchronous on a relatively short time scale. On a long time scale the temperature fluctuations is more than that of precipitation. This means that the number of the cold/warm period of temperature is more than that of precipitation. But the lasting time of the cold/warm period is shorter than that of precipitation. Although temperature and precipitation are positively correlated on a century scale, precipitation lagged temperature about 50～100a. This is more evident during the temperature decreasing period.

关 键 词：冰芯记录 树轮记录 青藏高原 对比研究 古气候变化 

分 类 号：P532[天文地球—古生物学与地层学]