Cosmogenic Radionuclides in the Siple Dome Ice Core

该奖项支持一项为期三年的更新项目，该项目将完成simple Dome冰芯中宇宙生成核素的测量，该项目是南极西部冰芯计划的一部分。研究人员将继续测量整个冰芯中铍-10（半衰期= 1.5 × 10.6年）和氯-36（半衰期= 3.0 × 10.5年）的剖面，这段时间跨度从现在到大约100 kyr。将南极记录与这些调查人员作为GISP2项目的一部分测量的详细北极记录进行比较，将特别具有指导意义。这种比较将有助于区分不同钻井地点的全球影响和局部影响。极地冰芯中的宇宙成因放射性核素已被用于研究几个重要的地球物理变量的长期变化，包括太阳活动、地磁场强度、大气环流、积雪率等。这项工作产生的核素浓度时间序列将应用于几个问题领域：完善冰芯年代学，推断太阳活动的历史，推断地磁场的变化历史，研究太阳变化对气候的可能作用。通过对不同冰芯中铍-10和氯-36剖面的比较，可以改进冰芯年代学，并直接比较全球不同地区的冰芯。与碳-14记录的进一步比较将使冰芯古环境记录与其他碳-14年代的古气候记录进行对比。

This award supports a three-year renewal project to complete measurement of cosmogenic nuclides in the Siple Dome ice core as part of the West Antarctic ice core program. The investigators will continue to measure profiles of Beryllium-10 (half-life = 1.5x10 6 years) and Chlorine-36 (half-life = 3.0x10 5 years) in the entire ice core which spans the time period from the present to about 100 kyr. It will be particularly instructive to compare the Antarctic record with the detailed Arctic record that was measured by these investigators as part of the GISP2 project. This comparison will help separate global from local effects at the different drill sites. Cosmogenic radionuclides in polar ice cores have been used to study the long-term variations in several important geophysical variables, including solar activity, geomagnetic field strength, atmospheric circulation, snow accumulation rates, and others. The time series of nuclide concentrations resulting from this work will be applied to several problem areas: perfecting the ice core chronology, deducing the history of solar activity, deducing the history of variations in the geomagnetic field, and studying the possible role of solar variations on climate. Comparison of Beryllium-10 and Chlorine-36 profiles in different cores will allow us to improve the ice core chronology and directly compare ice cores from different regions of the globe. Additional comparison with the Carbon-14 record will allow correlation of the ice core paleoenvironment record to other, Carbon-14 dated, paleoclimate records.