Collaborative Research: Water on the Antarctic Ice Sheet: Quantifying Surface Melt and Mapping Supraglacial Lakes

南极冰盖表面冰雪的融化会导致融水湖的形成，这是冰架崩塌和加速冰盖质量损失的重要前兆。了解南极表面融化的现状，为衡量未来融化影响的演变速度提供了一个基线，并减少了对未来海平面上升估计的不确定性。该项目将使用一套来自地球观测卫星、地面观测、数值气候和冰架模型的配套测量数据，以加强对地表融化和湖泊以及这些系统之间联系过程的了解。该项目直接支持1名博士后和若干名本科生科研人员的科学培养。此外，它还将通过与一名教育和外联专家和两名高中教师合作建立和执行一个教育单位，促进公众的科学素养和扩大高中学生的数量技能。准确预测来自南极洲的海平面贡献关键需要了解当前的融化和冰川上湖泊状况。这个项目将量化南极表面融化和冰川上湖泊，以及这两种现象之间的联系。散射计数据将能够生成一个19年的多传感器熔化时间序列。合成孔径雷达数据将以迄今为止最高的空间分辨率（40米）记录南极所有冰架的融化情况。多光谱卫星图像将用于描绘和测量冰上湖的深度，首次研究南极冰上湖的时空变化。将对融水和湖泊的观测结果进行比较，以确定一致和不一致。融冰观测将用于评估一个广泛使用的、由再分析驱动的区域气候模式的偏差。然后，这个模型将用于检查与冰川上湖泊有关的气候和冰川学变量。最后，现场观测和气候模式输出将驱动一个数值模式，模拟地表融化的整个生命周期和随后可能形成的湖泊。

Melting of snow and ice at the surface of the Antarctic ice sheet can lead to the formation of meltwater lakes, an important precursor to ice-shelf collapse and accelerated ice-sheet mass loss. Understanding the present state of Antarctic surface melt provides a baseline to gauge how quickly melt impacts could evolve in the future and to reduce uncertainties in estimates of future sea-level rise. This project will use a suite of complimentary measurements from Earth-observing satellites, ground observations, and numerical climate and ice-shelf models to enhance understanding of surface melt and lakes, as well as the processes linking these systems. The project directly supports the scientific training of a postdoctoral associate and several undergraduate researchers. In addition, it will promote public scientific literacy and the broadening of quantitative skills for high-school students through the development and implementation of an educational unit in a partnership with an education and outreach expert and two high school teachers.Accurate prediction of sea-level contributions from Antarctica critically requires understanding current melting and supraglacial lake conditions. This project will quantify Antarctic surface melt and supraglacial lakes, and the linkages between the two phenomena. Scatterometer data will enable generation of a 19-year multi-sensor melt time series. Synthetic aperture radar data will document melt conditions across all Antarctic ice shelves at the highest spatial resolution to date (40 m). Multispectral satellite imagery will be used to delineate and measure the depth of supraglacial lakes--for the first time studying the spatial and temporal variations of Antarctic supraglacial lakes. Melt and lake observations will be compared to identify agreement and disagreement. Melt observations will be used to evaluate biases in a widely used, reanalysis-driven, regional climate model. This model will then be used to examine climatic and glaciological variables associated with supraglacial lakes. Finally, in situ observations and climate model output will drive a numerical model that simulates the entire lifecycle of surface melt and possible subsequent lake formation.