High Precision Borehole Temperature Measurements at Siple Dome, Antarctica, for Paleoclimate Reconstruction and Ice Dynamics Studies

9726078沃丁顿该奖项支持一个项目，以获得一些高精度的钻孔温度剖面在西普尔圆顶古气候重建和冰动力学研究。 将在1 km深的充满流体的Siple Dome钻孔和沿沿着横跨Siple Dome的20 km南北断面的几个160 m深的钻孔中获得连续温度记录。 钻孔温度数据将用于：a）建立冰盖基底界面的传导热通量，B）利用地球物理反演方法重建Siple Dome的表面温度历史（“钻孔古温度测量”），c）限制威斯康星州晚期冰盖的厚度，威斯康星州/全新世冰消期变暖的幅度，和背景地热通量; d）确定过去Siple Dome氧同位素古温度计的校准常数; e）建立主钻场附近近百年来20 km尺度地表温度的空间变化。 Siple Dome的结果预计将提供评估西南极冰盖短期稳定性所需的数据，提高我们对这个南半球站点过去温度变化幅度的理解，并改进对过去孔隙封闭年龄的估计，从而改进Siple Dome冰芯的年龄尺度。

9726078 Waddington This award supports a project to obtain a number of high- precision borehole temperature profiles at Siple Dome for paleoclimate reconstruction and ice dynamics studies. Continuous temperature logs will be obtained in the 1 km deep fluid-filled Siple Dome borehole and in several 160 m deep holes along a 20 km north-south transect across Siple Dome. The borehole temperature data will be used to: a) establish the conductive heat flux across the basal interface of the ice sheet, b) reconstruct the surface temperature history at Siple Dome using geophysical inverse methods ("borehole paleothermometry"), c) constrain how thick the ice sheet was during the late Wisconsin, the magnitude of the Wisconsin/Holocene deglacial warming, and the background geothermal heat flux, d) determine the calibration constants for the oxygen-isotope paleothermometer at Siple Dome in the past, and e) establish the spatial variability of surface temperature on the 20 km scale near the main drill site during the last 100 years. The results at Siple Dome are expected to provide data needed to assess the short-term stability of the West Antarctic Ice Sheet, improve our understanding of the magnitude of past temperature changes at this southern hemisphere site, and lead to improved estimates of the pore close-off ages in the past which should lead to an improved age scale for the Siple Dome ice core.