【摘要】 北极阿拉斯加巴罗 (Barrow)地区 ( 70°2 1′N ,15 6°4 0′W )位于北极滨海平原最北端 ,根据湖泊钻孔花粉记录 ,2 10 Pb和13 7Se测定以及多项环境代用指标测试 (有机质含量、总C和总N含量、CaCo3 ) ,并结合当地现代冻原植被、表层花粉谱、当地 70a的气象记录以及有关的冰芯、树龄等资料的综合对比研究 ,分析了 13世纪以来巴罗地区气候和环境变化历史 .大约在 13世纪以前 ,巴罗地区植被稀少 ,气候寒冷 ,其后冻原植被发育良好 ,并经历几次演变 .结合沉积地球化学元素测试结果和其他环境代用资料研究表明 ,小冰期以来Barrow地区曾发生 3次暖期 (公元 15 4 0— 16 0 0年 ,16 6 0— 1730年和1880— 1992 )和 3次冷期 (公元 14 4 0— 15 2 0年 ,16 10— 16 5 0年和 175 0— 185 0年 ) .这些冷暖事件与青藏高原冰芯记录对比发现 ,虽然在高频变化上 ,不同地区存在着差异 ,但重大冷暖事件都曾出现 .其中 3次暖期与青藏高原古里雅冰芯和敦德冰帽中代表温度变化的δ18O值指示的暖期基本一致 ,证实巴罗湖芯记录的环境变化序列是可靠的 .同时 ,古里雅和敦德冰芯记录中反映传统小冰期中的 15 ,17,和 19世纪的 3次冷期 ,在巴罗湖芯记录中都有显示 .更多还原

【Abstract】 Barrow is located in the northeast of Alaskan coastal plain （71°20′ N, 156°40′ W）, which is encircled by the Chukchi Sea in the west and the Beaufort Sea in the north. Barrow is a quite cold area with the mean annual temperature of \{-12.4\} ℃, the mean temperature of \{-29 ℃\} in winter and 20℃ in summer. Mean annual precipitation is less than 250 mm.\;For understanding the climatic and environmental changes in Barrow, 9 lake cores, 100～350 cm in depth, were taken by piston corer in this area. Based upon the analyses and measurements of \{\} 210 Pb, \{\} 137 Cs, TOC, TN, organic materials, CaCO 3 , grain size and pollen of Core 98-4B, climatic and environmental records since 13 th century in Barrow were reconstructed.\;It is found that in the past 700 a, there were four main warm periods in 1240\₁425, 1535\₁600, 1720\₁730 and 1880\₁992, and three cold periods in 1440\₁520, 1605\₁650 and 1750\₁850. \;Comparative study shows that the Barrow lake core record is compatible with three main cold-warm conditions since the Little Ice Age deduced from the Guliya and Dunde ice cores and the tree ring record in the Qilian Mountains, although there exist some differences in high frequent climatic change.更多还原