A Geospatial Analysis of Glacier Volume Change

该项目将对冰川体积变化进行数据驱动的全球评估，并客观量化不确定性。海洋热膨胀（由于海洋温度上升）和山区冰川冰损失（由于冰川融化率增加）是造成全球平均海平面上升的主要原因，预计至少在未来世纪将继续主导海平面上升。不幸的是，最近的冰川对SLR的贡献和目前的冰川冰量的不确定性仍然很高，部分原因是冰川体积变化的数据有限。该项目对历史冰川变化和当前冰川体积的改进估计将为评估SLR变化、量化冰川对环境变异的敏感性以及提供未来SLR及其相关社会影响的准确预测迈出关键一步。 该项目将涉及本科生和研究生，并将为K-12教室开发教育实验室套件。这些工具包将向学校教师和学生介绍这项研究的结果，同时提供实际操作的真实的世界地理和空间科学练习。 拟议的工作将量化过去大约150年来区域冰川体积/质量的变化，以大大改善对冰川变化的空间和时间估计以及对SLR的相关贡献。 调查人员将把地球仪上所有的高山冰川和冰盖都纳入他们的分析。 研究人员还将利用研究初始阶段的观测结果来量化冰川冰体积的当前空间分布，以约束冰川模型。 这将通过将各种技术（自动云特征化方案、自然灾害影响指数、摄影测量、摄影测斜）结合起来，应用于一套遥感数据和历史图像，以绘制过去几十年冰川面积和体积变化图。 研究人员将利用这些信息来限制冰川体积面积缩放模型的空间变化比例因子。这项工作将通过编制可靠的冰碛日期和地图，以及自动绘制小冰期冰碛图，及时追溯到小冰期（LIA）。 将计算LIA结束时的冰量，这将允许将冰川体积变化的空间和时间模式置于与评估人为变化相关的背景下。这些新的冰川体积和体积变化估计将用于估计冰川过去和未来对SLR的贡献的区域模式，并确定冰川变化和对未来SLR的贡献可能很大的具体区域。因此，该研究项目将重点关注冰川对全球SLR的贡献，并将为估计SLR在许多国家（包括美国）的影响提供新的见解。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This project will provide a data-driven, global assessment of glacier volume changes with objectively quantified uncertainties. Ocean thermal expansion (due to increasing ocean temperatures) and mountain glacier ice loss (due to increased glacier melt rates) have contributed most to global mean sea level rise (SLR) and are expected to continue to dominate SLR over at least the coming century. Unfortunately, the uncertainties in recent glacier contributions to SLR and current volume of glacier ice remain high due, in part, to limited data on glacier volume changes. The improved estimates of historical glacier changes and current glacier volume from this project will provide a critical step towards assessing changes in SLR, quantifying glacier sensitivity to environmental variability, and providing accurate projections of future SLR and its associated societal impacts. This project will involve undergraduate and graduate students and will also develop educational lab kits for K-12 classrooms. These kits will communicate the results of this research to school teachers and students, while simultaneously providing hands-on, real world, geographical and spatial science exercises. The proposed work will quantify regional glacier volume/mass changes over the past approximately 150 years to significantly improve the spatial and temporal estimates of glacier changes and the associated contributions to SLR. Investigators will include all mountain glaciers and ice caps across the globe in their analysis. The investigators will also quantify the current spatial distribution of volume of glacier ice using observations from the initial phase of the research to constrain a glacier model. This will be accomplished using a combination of techniques (automated cloud characterization schemes, NDSI, photogrammetry, photoclinometry) applied to a suite of remotely sensed data and historical imagery to map glacier area and volume changes over the past several decades. The investigators will use this information to constrain spatially-varying scale factors for a glacier volume-area scaling model. This work will extend back in time to the Little Ice Age (LIA) by compiling reliable moraine dates and maps, and automated mapping of LIA moraines. The volume of ice around the end of the LIA will be calculated, which will permit placing the spatial and temporal patterns in glacier volume change into context relevant to assess anthropogenic changes. These new glacier volume and volume change estimates will be used to estimate regional patterns of past and future contributions of glaciers to SLR and identify specific regions where glacier changes and contributions to future SLR are likely to be significant. Thus, this research project will focus on glacier contribution to SLR globally and will provide new insights estimating the impacts of SLR in many countries, including the United States.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.