COLLABORATIVE RESEARCH: Elevation Change Anomalies in West Antarctica and Dynamics of Subglacial Water Transport Beneath Ice Streams and their Tributaries

Tulaczyk/0636970该奖项支持一个研究高程变化异常（以下简称ECA）的项目，这些异常是在西南极冰盖（WAIS）罗斯海部分的几个地点的遥感图像中观察到的椭圆形，5至10公里的区域。在这些异常中，地表高程的变化率高达每天~1至~2厘米，明显快于周围地区。这些异常被认为是由数千米规模的冰下水囊的填充和排泄造成的。 该项目的智力价值在于，这些ECA代表了一个前所未有的窗口，可以进入现代南极冰盖下难以捉摸的排水动力学世界。虽然冰下水通量与正常陆地条件相比很小，但它们在控制快速冰流和潜在的冰盖稳定性方面发挥着重要作用。缺乏观测的限制下冰盖水动力学的冰流和冰盖的定量建模的进展是最重要的限制之一。这种模型对于评估未来冰盖质量平衡和重建冰盖对过去气候变化的反应是必要的。动态冰盖下的水输送所指示的ECA也可能有影响的冰下湖泊和其他冰下环境，这可能是生活适应这种极端条件的研究。 该项目更广泛的影响是，它将为一名博士后研究员（UW），两名女博士生（UCSC）提供高级培训机会，他们将增强极地科学的多样性，以及至少三名本科生（UCSC）。 项目产出将与广泛的科学和社会利益相关，如未来全球海平面变化和极地地区对气候变化的反应。自由科学记者道格拉斯福克斯有兴趣加入第一个实地季，为科普杂志撰写专题文章，并促进该项目和南极科学在大众媒体上的曝光。

Tulaczyk/0636970This award supports a project to study elevation change anomalies (henceforth ECAs), which are oval-shaped, 5-to-10 km areas observed in remote sensing images in several locations within the Ross Sea sector of the West Antarctic Ice Sheet (WAIS). Within these anomalies, surface elevation changes at rates of up to ~1 to ~2 cm per day, significantly faster than in surrounding regions. These anomalies are thought to result from filling and draining of multi-kilometer-scale subglacial water pockets. The intellectual merit of this project is that these ECA's represent an unprecedented window into the elusive world of water drainage dynamics beneath the modern Antarctic ice sheet. Although subglacial water fluxes are small compared to normal terrestrial conditions, they play an important role in controlling fast ice streaming and, potentially, stability of the ice sheet. The dearth of observational constraints on sub-ice sheet water dynamics represents one of the most important limitations on progress in quantitative modeling of ice streams and ice sheets. Such models are necessary to assess future ice sheet mass balance and to reconstruct the response of ice sheets to past climate changes. The dynamic sub-ice sheet water transport indicated by the ECAs may have also implications for studies of subglacial lakes and other subglacial environments, which may harbor life adapted to such extreme conditions. The broader impacts of this project are that it will provide advanced training opportunities to one postdoctoral fellow (UW), two female doctoral students (UCSC), who will enhance diversity in polar sciences, and at least three undergraduate students (UCSC). Project output will be relevant to broad scientific and societal interests, such as the future global sea level changes and the response of Polar Regions to climate changes. Douglas Fox, a freelance science journalist, is interested in joining the first field season to write feature articles to popular science magazines and promote the exposure of this project, and Antarctic Science in general, to mass media.