Collaborative Research: Long-Term and Interannual Variability of Antarctic Ice Sheet Mass Balance From Satellite Gravimetry and Other Geodetic Measurements

该奖项支持一个项目，该项目利用重力恢复和气候实验（GRACE）的卫星重力测量和其他大地测量数据，改进对大陆、区域和流域尺度上南极冰盖质量平衡的长期和年际变化的估计。这项工作将利用更长的记录和新一代产品改进GRACE重力数据对南极洲长期质量变化率的量化，并将开发先进的数值正演模拟技术，以准确纠正与GRACE数据处理相关的泄漏效应，并显著提高GRACE质量率估算的空间分辨率。这项工作还将有助于通过冰后反弹（PGR）模型、GPS测量以及GRACE和ICESat高程变化的综合分析，更好地了解由于冰后反弹（PGR）引起的地壳隆起率和南极洲目前冰负荷的变化。将在大陆和集水区尺度上调查南极洲冰盖的年际变化，并研究其与区域气候变化的关系。这项研究的主要成果将是改进对整个南极冰盖冰质量平衡的评估，以及对全球平均海平面上升的潜在贡献。这项工作还将提供南极洲区域冰质量变化率的估计，重点是沿着阿蒙森海海湾、西南极洲半岛以及东南极洲的威尔克斯地和维多利亚地的海岸。还将估算南极洲不同空间尺度上的年际冰量变化，并评估GRACE冰率估算和PGR模式误差的不确定性。该研究的学术价值包括：1)以前所未有的精度改进了不同时空尺度的南极冰块平衡评估，为极地科学研究的广泛领域做出了重要贡献；2)结合高精度GPS垂直隆升测量和PGR模型，更好地量化GRACE对地壳隆升的长期影响。3)统一基于多种现代空间大地测量观测的冰盖和冰川物质平衡与地壳隆升量化前沿的若干研究工作。更广泛的影响包括，通过两名研究生的支持，该项目将积极吸引学生参与和培训。此外，该项目还将促进普通教育和公众宣传活动（E/PO），这项调查的结果将有助于激励未来的地球科学家，并提高公众对气候变化重大表现形式的认识。

1043750/ChenThis award supports a project to improve the estimate of long-term and inter-annual variability of Antarctic ice sheet mass balance at continental, regional, and catchment scales, using satellite gravity measurements from the Gravity Recovery and Climate Experiment (GRACE) and other geodetic measurements. The work will improve the quantification of long-term mass change rates over Antarctica using GRACE gravity data with a longer record and newer generation(s) of products and will develop advanced numerical forward modeling techniques that can accurately correct leakage effects associated with GRACE data processing, and significantly improve spatial resolution of GRACE mass rate estimates over Antarctica. The work will also contribute to a better understanding of crustal uplift rates due to postglacial rebound (PGR) and present day ice load change over Antarctica via PGR models, GPS measurements, and combined analysis of GRACE and ICESat elevation changes. Inter-annual variations of ice mass over Antarctica will be investigated at continental and catchment scales and connections to regional climate change will be studied. The major deliverables from this study will be improved assessments of ice mass balance for the entire Antarctic ice sheet and potential contribution to global mean sea level rise. The work will also provide estimates of regional ice mass change rates over Antarctica, with a focus along the coast in the Amundsen Sea Embayment, the Peninsula in West Antarctica, and in Wilkes Land and Victoria Land in East Antarctica. Estimates of inter-annual ice mass change over Antarctica at various spatial scales, and assessments of uncertainty of GRACE ice rate estimates and PGR models errors over Antarctica will also be made. The intellectual merits of the proposed investigation include 1) providing improved assessments of Antarctic ice mass balance at different temporal and spatial scales with unprecedented accuracy, an important contribution to broad areas of polar science research; 2) combining high accuracy GPS vertical uplift measurements and PGR models to better quantify long-term crust uplift effects that are not distinguishable from ice mass changes by GRACE; and 3) unifying the work of several investigations at the forefront of quantifying ice sheet and glacier mass balance and crustal uplift based on a variety of modern space geodetic observations. The broader impacts include the fact that the project will actively involve student participation and training, through the support of two graduate students. In addition the project will contribute to general education and public outreach (E/PO) activities and the results from this investigation will help inspire future geoscientists and promote public awareness of significant manifestations of climate change.