南极地区数百年来气候变化的冰芯记录对比研究

随着国际横穿南极科学考察计划的实施, 近年来开展了沿中山站-Dome A考察路线的冰芯研究, 获得了伊丽莎白公主地250 a来气候环境变化的高分辨率记录. 通过与Lambert冰川流域西侧有关研究结果的对比, 揭示了该冰川谷地为东南极洲重要气候分界线的特征. 综合南极地区其它地点冰芯记录和冰盖变化研究结果, 发现以小冰期为代表的寒冷期在东南极洲较为明显, 在西南极洲则不明显, 甚或恰好相反, 表现为温暖阶段. 就东南极洲来说, 也存在明显的区域差异: 以Lambert冰川谷地为界, 东部地区, 如Wilkes Land (Law Dome), Victoria Land北部(Hercules Neve)等地, 小冰期冷期比较突出;西部地区, 如Dronning Maud Land和Mizuho高原, 情况不是很明确. Lambert冰川流域是非常特殊的地方, 虽然小冰期冷期也存在, 但1850年前后的显著高温和近100多年来的降温与南极洲其它地方都不一样, 而与南极半岛北侧一冰芯所给出的400 a温度变化记录极为相似, 我们尚不能解释为何如此遥远的两个地点具有很好的一致性而与其它地方则不一致.

Comparison of Ice-core Records of Climatic Change over Past Centuries in Antarctica

Following the International Trans-Antarctic Scientific Expedition, inland traverses for glaciological investigation have been made along a route from Zhongshan Station to Dome A. The shallow cores drilled during these traverses have revealed a 250 year high\|resolution record of climatic change in the west Princess Elizabeth Land, i.e. east side of the Lambert Glacier basin. Comparison with the results in west side of the basin shows that the Lambert Glacier valley is an important boundary of climate in East Antarctica. On the whole Antarctica, the ice\|core records indicate that the cold period characterized by the Little Ice Age (LIA) is relatively strong in East Antarctica, while it is weak or even contrary in West Antarctica. Again in East Antarctica, some differences between east and west of the Lambert Glacier valley can be still seen. In east, such as Wilkes Land (Law Dome) and north Victoria Land (Hercules Neve), the cold period of LIA is striking, but in west, such as Dronning Maud Land and Mizuho Plateau, it is relatively weak. The Lambert Glacier basin is exceptional, where although the LIA cold period exists, a remarkable high temperature stage around 1850 and the temperature decrease since then are very different from other regions in East Antarctica but quite consistent with a 400year record from a core in an island of north Antarctic Peninsula. This is hard to be explained at present.