Assessing topographic impacts on tropical glacier extent and moraine formation

评估地形对热带冰川范围和冰碛形成的影响

• 批准号: 2022727
• 负责人: Meredith Kelly
• 金额: $ 36.83万
• 依托单位: Dartmouth College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2022727&HistoricalAwards=false
• 关键词: Assessing; topographic; impacts; tropical; glacier

Many mountain glaciers are currently retreating as a result of climate change, and decades of research have used past glacial fluctuations (advances and retreats) to understand the mechanisms of past climate change. Yet, mountain glaciers are also influenced by underlying topography (e.g., the mountain height above a glacier and valley slope beneath a glacier). This project examines the influence of topography on glacial extents using computer modeling in conjunction with reconstructions of past glacial extents in mountain ranges in Uganda and Colombia. The small footprint of these tropical mountain ranges makes it likely that neighboring valleys experience similar climate conditions and, thus, any differences in glacial extents should be due to topographic differences among the valleys. Moreover, Uganda and Colombia are among the few tropical locations where long-term records of glacial changes in multiple adjacent valleys may be obtained. The project will improve the ability to forecast future glacial changes and model landscape evolution. It will also advance the use of past glacial extents to understand the causes of past climate changes. The project supports an international tropical glacier workshop and the development of high school STEM activities that aim to broaden participation of underrepresented groups. It also supports two early career female researchers in a domain of science where women remain highly underrepresented.The project will use glacial modeling in combination with modern climate data and surface exposure dating of glacial moraines (ridges that mark former glacial extents) to assess topographic impacts on tropical glacial extents and moraine formation. It has the following two objectives: 1) assess how variations in specific topographic characteristics influence glacial extents using glacial modeling with idealized digital elevation models; and 2) assess how variations in topography influenced past glacial extents in two tropical mountain ranges (the Rwenzori Mountains in Uganda and the Sierra Nevada del Cocuy in Colombia) using glacial modeling and surface exposure dating of moraines. The project will provide one of the few datasets available to examine the relative impacts of climate and topography on glacial extents and, thus, advance the ability to model the response of glaciers to future climate changes. It will also improve the ability to infer past climate conditions from the geomorphic record of glacial extents.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.

由于气候变化，许多山地冰川目前正在撤退，数十年来的研究使用了过去的冰川波动（进步和务虚会）来了解过去气候变化的机制。然而，山地冰川也受到潜在地形的影响（例如，冰川下方的山地高度高于冰川下方）。该项目使用计算机建模与乌干达和哥伦比亚山区过去冰川范围的重建相结合的计算机建模研究了地形对冰川范围的影响。这些热带山区的占地面积很小，使附近的山谷可能经历相似的气候条件，因此，冰川量的任何差异都应归因于山谷之间的地形差异。此外，乌干达和哥伦比亚是少数热带地点之一，可以获得多个相邻山谷中冰川变化的长期记录。该项目将提高预测未来冰川变化并建模景观演变的能力。它还将推动使用过去的冰川范围，以了解过去气候变化的原因。该项目支持国际热带冰川研讨会和高中STEM活动的发展，旨在扩大代表性不足的群体的参与。它还支持在一个科学领域中的两名早期职业女性研究人员，在该领域中，女性的代表性不足。该项目将使用冰川建模与现代气候数据结合使用冰川数据和冰川冰原的表面暴露约会（标志着前冰川景象的山脊）来评估对热带冰川扩展和莫雷纳的地形影响。它具有以下两个目标：1）评估特定地形特征的变化如何使用理想化的数字高程模型使用冰川建模来影响冰川范围； 2）评估使用冰川建模和莫拉氏菌的表面暴露约会的两个热带山脉（乌干达的rwenzori山脉和哥伦比亚山脉的山脉山脉和内华达州内华达州的山脉）如何影响过去的冰川范围。该项目将提供少数可用的数据集之一，以检查气候和地形对冰川扩展的相对影响，从而提高对冰川对未来气候变化的响应进行建模的能力。它还将提高从冰川范围的地貌记录中推断出过去的气候条件的能力。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛的影响评估标准通过评估来获得支持的。