Stable Isotope Studies at East Antarctic US ITASE Sites

该奖项支持一个从东南极洲浅层（100米）冰芯中获取稳定同位素剖面的项目，以增加在“ITASE”（国际跨南极科学考察）项目主持下收集的日益增长的环境代理数据数据库。在南极洲，对气候的仪器记录特别短（约40年，除了海岸上少数孤立的地点），而冰芯代用数据是将这一记录延续到过去的唯一可用手段。利用冰芯中水的稳定同位素（18-O/16-O和D/H比值）作为温度的代用指标，在极短（即季节）和长时间尺度（数百年、数千年）都得到了很好的证实。利用多元回归方法和南极西部的浅冰芯，对过去~150年的南极气候进行了重建，结果表明南极大陆一直在以平均~0.2 K/世纪的速度变暖。进一步改进这些重建是进一步扩展美国ITASE项目的主要动机。将获得并分析东南极洲维多利亚地10至15个浅层（~ 100米）。核心将沿着一条从泰勒巨蛋开始到南极结束的穿越路线收集。岩心的年龄-深度关系将通过稳定同位素、视觉地层学、季节性化学特征和标志层位的组合来确定。从这些岩心获得的南极气候重建将被纳入全球古气候信息网络，这在科学、政策和教育环境中具有重要意义。该项目将包括研究生和博士后培训以及实地经验。

This award supports a project to obtain stable isotope profiles from shallow (100 m) ice cores from East Antarctica, to add to the growing database of environmental proxy data collected under the auspices of the "ITASE" (International TransAntarctic Scientific Expedition) program. In Antarctica, the instrumental record of climate is particularly short (~40 years except in a few isolated locations on the coast), and ice core proxy data are the only means available for extending this record into the past. The use of stable isotopes of water (18-O/16-O and D/H ratios) from ice cores as proxies for temperature is well established for both very short (i.e. seasonal) and long timescales (centuries, millennia). Using multivariate regression methods and shallow ice cores from West Antarctica, a reconstruction of Antarctic climate over the last ~150 years has been developed which suggests the continent has been warming, on average, at a rate of ~0.2 K/century. Further improving these reconstructions is the chief motivation for further extending the US ITASE project. Ten to fifteen shallow (~ 100 m) from Victoria Land, East Antarctica will be obtained and analyzed. The core will be collected along a traverse route beginning at Taylor Dome and ending at the South Pole. Age-depth relationships for the cores will be determined through a combination of stable isotopes, visual stratigraphy and seasonal chemical signatures and marker horizons. Reconstructions of Antarctic climate obtained from these cores will be incorporated into the global network of paleoclimate information, which has been important in science, policy and educational contexts. The project will include graduate student and postdoctoral training and field experience.