东南极LGB69冰芯1712-2001年气温变化记录的初步研究  

Preliminary Study on Air Temperature Records from 1712 to 2001 Revealed by LGB69 Ice Core in East Antarctica

作　　者：张子洋[1,2] 闫明[1] MULVANEY Robert 季峻峰[2] 效存德 刘雷保[1] 安春雷[1] ZHANG Ziyang;YAN Ming;MULVANEY Robert;JI Junfeng;XIAO Cunde;LIU Leibao;AN Chunlei(Polar Research Institute of China,Shanghai 200136,China;Key Laboratory of Surficial Geochemistry,Ministry of Education,Nanjing University,Nanjing 210023,China;British Antarctic Survey,High Cross,Madingley Road,Cambridge CB30 ET,UK;Northwest Institue of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 130000,China)

机构地区：[1]中国极地研究中心,上海200136 [2]南京大学表生地球化学教育部重点实验室,江苏南京210023 [3]British Antarctic Survey,High Cross,Madingley Road’Cambridge CB30ET,UK [4]中国科学院西北生态环境资源研究院,甘肃兰州730000

出　　处：《地球科学进展》2021年第2期172-184,共13页Advances in Earth Science

基　　金：国家自然科学基金项目“极地冰芯中记录的火山作用及其对气候的影响”(编号:41676192)资助。

摘　　要：南极冰芯记录着过去气温、降水等气候环境参数以及影响其变化的太阳活动、火山作用等各种因子变化,是研究古气候、古环境变化及其影响机制的良好载体。东南极LGB69冰芯高分辨率的地球化学分析表明:(1)该冰芯的水当量年平均积累率高达259 mm/a,利用δ18O和Na+季节性变化和火山喷发标志层,通过数年层的方法确定其沉积时间为290 a(1712-2001年)±2 a;(2)该冰芯δ18O与邻近的戴维斯站气温距平5年滑动平均值(1968-2001年)之间具有良好的正相关关系,是有效的气温代用指标,1712-2001年该地区气温是一个波动变暖的过程,划分为4个阶段,小冰期结束于1914年,20世纪5年滑动平均气温距平年平均值较小冰期末次冷阶段升高0.30℃;(3)Morlet小波分析表明,1712-2001年该冰芯δ18O(气温)和积累率(降水量)均存在约11年、约22年和约60年的共同周期,多重时间周期的嵌套表明其对气候变化非常敏感。上述研究结果为进一步重建南极气候冷暖、降水序列变化,以及研究太阳活动、火山作用等因子对气候变化影响的内在规律奠定了基础。Antarctic ice core is an ideal paleoclimatic and paleoenvironmental carrier,which records the past variations of various parameters such as air temperature,precipitation and their major factors,e.g.solar activity,volcanism.High-resolution geochemical analyses of LGB69 ice core,East Antarctica show that(1)Based on the combination of seasonal variations ofδ18 O and Na+with volcanic eruption markers,LGB69 ice core is dated to 290 a(A.D.1712-A.D.2001)±2 a through annual layer counting,with a high average annual accumulation rate of 259 mm w.e./a;(2)Five-year moving average(A.D.1968-A.D.2001)ofδ18 O of LGB69 ice core has good positive correlation with that of temperature departure at adjacent Davis Station,indicating thatδ18 O is an effective proxy for air temperature.Air temperature from A.D.1712 to A.D.2001 in LGB69 region is a process of fluctuating warming,which can be divided into four stages.The average annual value of 5-year moving average temperature departure is 0.30℃higher than that of last cold stage in the Little Ice Age which ended in A.D.1914;(3)By Morlet wavelet analysis,bothδ18 O(air temperature)and accumulation rate(precipitation)of LGB69 ice core from A.D.1712 to A.D.2001 present ca.11-year,ca.22-year and ca.60-year cycles.Multinest of cycles forδ18 O,accumulation rate of LGB69 ice core implies its sensitivity to climate change.The above-mentioned results build up a good basis for further research on the reconstruction of temporal variations in air temperature and precipitation and the effects of factors such as solar activity,volcanism on climate change in Antarctica.

关 键 词：南极 冰芯 定年 气候变化 稳定氧同位素 积累率 

分 类 号：P343.6[天文地球—水文科学]