CAREER: What's Past is Prologue: Seamless Assimilation of Past Observations into Simulations of Future Ice Sheets

认识到海平面上升及其对沿海社区的潜在影响是各级政府和私营企业作出明智决策的先决条件。然而，在特定的排放途径下，未来冰盖对海平面上升的贡献的大部分不确定性来自不完全受约束的冰盖模型。在实践中，模型之间的校准数据和程序的差异导致2100年及以后的海平面预测存在很大的不确定性。为了最大限度地利用现代和地质观测对冰盖变化的好处，拟议的项目将采用应用数学和计算机科学的最新计算方法，将许多不同类型的观测同化为冰盖模型。最终，这些方法将被用来对过去多年时间尺度上的冰川状态进行无缝估计，并改进对未来冰盖变化的预测。该项目的教育部分将通过高中计算机科学课程扩展现有的关于海平面上升的基于标准的课程。该项目研究部分的主要重点是开发一个开放源码软件包，用于将瞬变集合卡尔曼滤波技术应用于各种冰盖模型，使冰川和地质观测与物理模型无缝结合。两个初步的案例研究将侧重于重建过去的冰川变化，并利用这些重建来初始化格陵兰的Sermeq Kujalleq(又名Jakobshavn Isbrae)和西南极的Thwaites冰川未来的变化预测。该项目的最后部分将把这些数据同化能力添加到基于云的冰盖模型中，该模型具有基于浏览器的界面，以便在模拟过去和未来的冰川行为期间，可以直接使用来自社区冰盖观测储存库的数据同化。教育部分将制定一项新的高中课程，重点是根据格鲁吉亚(和国家)计算机科学和统计课程的现有标准，以数据为基础探索过去和未来海平面上升及其驱动过程。该课程将与亚特兰大地区的一名教师和佐治亚理工学院的一名经验丰富的教育研究员合作开发，并在当地一所高中试行。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Awareness of sea level rise and its potential to impact coastal communities is a pre-requisite for informed decision-making at all levels of government and private industry. However, most of the uncertainty in future ice sheet contribution to sea level rise under particular emissions pathways comes from incompletely constrained ice sheet models. In practice, differences in calibration data and procedures between models lead to large uncertainties in sea level projections at 2100 and beyond. To make optimal use of the benefits of both modern and geological observations of ice sheet change, the proposed project will adapt state-of-the-art computational methods from applied mathematics and computer science to assimilate many different types of observations into ice sheet models. Ultimately, these methods will be used to produce gapless estimates of past glacier state over multimillennial time scales and improved projections of future ice sheet change. The educational component of this project will extend an existing standards-based curriculum on sea level rise through high school computer science courses. The main focus of the research component of this project is the development of an open-source software package for applying transient ensemble Kalman filtering techniques to a wide range of ice sheet models, enabling the seamless integration of glaciological and geological observations with physical models. Two initial case studies will focus on reconstructing past glacier changes and using these reconstructions to initialize future predictions of change at Sermeq Kujalleq (aka Jakobshavn Isbrae) in Greenland and Thwaites Glacier in West Antarctica. The final part of this project will add these data assimilation capabilities to a cloud-based ice sheet model with a browser-based interface so that it can be used to directly assimilate data from a community repository of ice sheet observations during simulations of past and future glacier behavior. The educational component will develop a new high school curriculum focused on data-based exploration of past and future sea level rise and its driving processes, in alignment with existing Georgia (and national) standards in Computer Science and Statistics courses. This curriculum will be developed in collaboration with an Atlanta-area teacher and an experienced education researcher at Georgia Tech, and piloted at a local high school.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.