Collaborative Research: Stable Isotopes of Ice in the WAIS Divide Deep Ice Core

该奖项支持对拟议中的西南极冰盖分水岭(WAIS)深冰芯中水的稳定同位素Dd、D18O和过量的重氢进行分析。该项目将为新的岩芯提供稳定的同位素比率的连续和高分辨率重建。Dd和d18O值提供了对冰核地点温度变化的估计。氚过量提供了对海洋表面条件的估计，例如在水汽源区的海洋表面温度。这个新的冰芯位于理想的位置，可以解决从冰盖稳定性到突然的气候变化等一系列问题。WAIS Divide有足够高的降雪率来记录年度到十年时间尺度上的气候变化。它还应该有足够古老的冰来详细捕捉最后的间冰期。随着现代气候变暖和海平面上升，西南极冰盖成为人们密切关注的对象。这个冰盖释放的冰有可能增加海平面上升的可能性是什么？了解这个冰盖过去是如何应对气候变化的，这一项目中收集的数据将有助于评估，这对回答这个问题至关重要。WAIS Divide核心提供的高时间分辨率将为两极之间千年尺度气候变化的相互比较提供最好的可用基础，从而更好地了解快速气候变化事件的空间表现和动态。最后，这个核心位于南极洲西部的太平洋部分，这使得它非常适合研究热带太平洋对南极洲气候的影响，其时间尺度比仪器气候记录所能获得的时间尺度更长。分析将包括测量岩心最顶部分年度分辨的同位素变化，在过去10 000年和之前的快速气候变化期间以年度分辨率测量，以及在本赠款期间收集和处理的整个岩心长度以50年分辨率测量。我们预计，这将是预计将钻探的全部岩芯的大约一半。在更广泛的影响方面，PI将分享两名研究生的建议，他们将把这个冰芯作为他们论文项目的重点。它将以创新的多校区方法进行，旨在培养更广泛的教育体验。如上所述，该提案产生的数据和解释将不仅涉及直接和直接的科学利益，而且也涉及直接和直接的政策利益。

This award supports analyses of stable isotopes of water, dD, d18O and deuterium excess in the proposed West Antarctic Ice Sheet Divide (WAIS) deep ice core. The project will produce a continuous and high-resolution reconstruction of stable isotope ratios for the new core. dD and d18O values provide estimates of temperature change at the ice core site. Deuterium excess provides estimates of ocean surface conditions, such as sea surface temperature, at the moisture source areas. This new ice core is ideally situated to address questions ranging from ice sheet stability to abrupt climate change. WAIS Divide has high enough snowfall rates to record climate changes on annual to decadal time scales. It should also have ice old enough to capture the last interglacial period in detail. The West Antarctic ice sheet is the subject of great scrutiny as our modern climate warms and sea level rises. What are the prospects for added sea level rise from ice released by this ice sheet? Understanding how this ice sheet has responded to climate change in the past, which the data collected in this project will help to assess, is critical to answering this question. The high temporal resolution available in the WAIS Divide core will provide the best available basis for inter-comparison of millennial-scale climate changes between the poles, and thus a better understanding of the spatial expression and dynamics of rapid climate change events. Finally, the location of this core in the Pacific sector of West Antarctica makes it well situated for examining the influence of the tropical Pacific on Antarctica climate, on longer timescales than are available from the instrumental climate record. Analyses will include the measurement of sub-annually resolved isotope variations in the uppermost parts of the core, measurements at annual resolution throughout the last 10,000 years and during periods of rapid climate change prior to that, and measurements at 50-year resolution throughout the entire length of the core that is collected and processed during the period of this grant. We anticipate that this will be about half of the full core expected to be drilled. In terms of broader impacts, the PIs will share the advising of two graduate students, who will make this ice core the focus of their thesis projects. It will be done in an innovative multi-campus approach designed to foster a broader educational experience. As noted above, the data and interpretations generated by this proposal will address climate change questions not only of direct and immediate scientific interest, but also of direct and immediate policy interest.